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rgba(255,255,255,.1);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px)}.btn-secondary:hover{background:var(--bg-card-hover);border-color:#fff3}.btn-danger{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:var(--space-md) var(--space-lg);border:none;border-radius:var(--radius-md);font-family:inherit;font-size:1rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;background:var(--danger);color:var(--text-primary)}.btn-danger:hover{background:#e74c3c}.btn-small{padding:var(--space-sm) var(--space-md);font-size:.875rem}.btn-large{padding:var(--space-md) var(--space-lg);font-size:1rem}@media (min-width: 480px){.btn-large{padding:var(--space-md) var(--space-xl);font-size:1.1rem}}.btn--ghost,.puzzle-btn,.duration-btn,.skip-btn{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:var(--space-md) 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.btn{width:100%;justify-content:center}.menu-buttons{display:flex;flex-direction:column;gap:var(--space-md);margin-bottom:var(--space-xl)}.btn-back,.back-button{position:absolute;top:var(--space-lg);left:var(--space-lg);background:none;border:none;color:var(--text-secondary);font-size:1rem;cursor:pointer;padding:var(--space-sm);transition:color var(--transition-fast)}.btn-back:hover,.back-button:hover{color:var(--text-primary)}.back-button{position:static;font-size:1.5rem;padding:var(--space-xs)}.back-button:hover{color:var(--accent)}.cta-button{display:inline-flex;align-items:center;gap:var(--space-sm);padding:var(--space-md) var(--space-xl);background:linear-gradient(135deg,#d4a843,#b8942f);color:#1a1a2e;box-shadow:var(--shadow-md),0 0 20px #d4a8434d}.cta-button:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg),0 0 30px #d4a84380;background:linear-gradient(135deg,#e0b44e,#c4a035)}.cta-button:active{transform:translateY(0)}.cta-button{font-size:1rem;border-radius:var(--radius-md);text-decoration:none}@media (min-width: 600px){.cta-button{padding:var(--space-md) var(--space-xxl);font-size:1.1rem}}.login-button{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:var(--space-md) var(--space-lg);border:none;border-radius:var(--radius-md);font-family:inherit;font-size:1rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;width:100%;padding:var(--space-md);background:var(--accent);color:var(--bg-dark);margin-top:var(--space-sm)}.logout-btn{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:var(--space-md) var(--space-lg);border:none;border-radius:var(--radius-md);font-family:inherit;font-size:1rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;padding:var(--space-sm) var(--space-lg);background:#c0392b33;color:#e74c3c;border:1px solid rgba(192,57,43,.3)}.puzzle-btn.hint-btn{background:#d4af371a;border-color:#d4af374d;color:var(--accent)}.puzzle-btn.hint-btn:hover{background:#d4af3733;border-color:var(--accent)}.puzzle-btn.flip-btn{background:#ffffff0d;color:var(--text-secondary)}.puzzle-btn.flip-btn:hover{background:#ffffff1a;color:var(--text-primary)}.puzzle-btn.next-btn{background:var(--accent);border-color:var(--accent);color:var(--bg-dark)}.puzzle-btn.next-btn:hover{background:var(--accent-light);border-color:var(--accent-light)}.puzzle-btn.retry-btn{background:#e67e2226;border-color:#e67e2266;color:#e67e22}.puzzle-btn.retry-btn:hover{background:#e67e2240;border-color:#e67e22}.puzzle-btn.primary{background:var(--accent);color:var(--bg-dark)}.puzzle-btn.primary:hover{background:var(--accent-light)}.puzzle-btn.secondary{background:#ffffff1a;color:var(--text-primary)}.puzzle-btn.secondary:hover{background:#fff3}.duration-btn{padding:var(--space-md) var(--space-xl);font-size:1.1rem;border:2px solid rgba(255,255,255,.1)}.start-rush-btn,.play-again-btn{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:var(--space-md) var(--space-lg);border:none;border-radius:var(--radius-md);font-family:inherit;font-size:1rem;font-weight:600;cursor:pointer;transition:all var(--transition-fast);text-decoration:none;padding:var(--space-md) var(--space-xxl);font-size:1.25rem;background:var(--accent);color:var(--bg-dark)}.start-rush-btn:hover,.play-again-btn:hover{background:var(--accent-light);transform:scale(1.02)}.play-again-btn{margin-bottom:var(--space-md);display:block;width:100%}.opening-btn{background:#ffffff1a;border:1px solid rgba(255,255,255,.2);color:var(--text-primary);width:40px;height:40px;border-radius:var(--radius-sm);cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:1rem;transition:background .2s,transform .2s}.opening-btn:hover{background:#fff3;transform:scale(1.05)}.difficulty-btn{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-sm) var(--space-md);background:var(--bg-card);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);text-align:left}@media (min-width: 480px){.difficulty-btn{padding:var(--space-md) var(--space-lg)}}.difficulty-btn .diff-icon{font-size:1.5rem;width:40px;text-align:center}@media (min-width: 480px){.difficulty-btn .diff-icon{font-size:2rem;width:50px}}.difficulty-btn .diff-name{font-size:1rem;font-weight:600;color:var(--text-primary);display:block}@media (min-width: 480px){.difficulty-btn .diff-name{font-size:1.1rem}}.difficulty-btn .diff-desc{font-size:.75rem;color:var(--text-secondary);display:block;margin-top:2px}@media (min-width: 480px){.difficulty-btn .diff-desc{font-size:.85rem}}.auth-link{color:var(--accent);text-decoration:none;font-weight:500}.auth-link:hover{text-decoration:underline}.card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-lg);text-decoration:none;color:var(--text-primary)}.card:hover{transform:translateY(-4px);border-color:#d4af374d;box-shadow:var(--shadow-lg)}@media (min-width: 600px){.card{padding:var(--space-xl)}}.feature-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-lg);text-align:center}@media (min-width: 600px){.feature-card{padding:var(--space-xl)}}.feature-card:hover{transform:translateY(-4px);border-color:#d4af374d;box-shadow:var(--shadow-lg)}.feature-card .feature-icon{font-size:2.5rem;display:block;margin-bottom:var(--space-md)}.feature-card h3{font-size:1.1rem;margin-bottom:var(--space-sm);color:var(--accent)}.feature-card p{color:var(--text-secondary);font-size:.9rem;line-height:1.6}.opening-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);display:block;padding:var(--space-lg);text-decoration:none;color:var(--text-primary);position:relative}.opening-card:hover{background:#d4af371a;border-color:#d4af374d;transform:translateY(-2px)}.opening-card .opening-card-title{font-size:1.1rem;font-weight:600;margin-bottom:var(--space-xs)}.opening-card .opening-card-subtitle{font-size:.85rem;color:var(--text-muted);font-style:italic;margin-bottom:var(--space-sm)}.opening-card .opening-card-eco{display:inline-block;background:var(--accent);color:var(--bg-dark);padding:2px 8px;border-radius:var(--radius-sm);font-size:.75rem;font-weight:600}.puzzle-link-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-md) var(--space-lg);text-decoration:none;color:var(--text-primary)}.puzzle-mode-card{display:flex;align-items:flex-start;gap:var(--space-md);padding:var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);border-radius:var(--radius-lg);text-decoration:none;color:inherit;position:relative;overflow:hidden}@media (min-width: 768px){.puzzle-mode-card{padding:var(--space-lg)}}.puzzle-mode-card:hover{background:var(--bg-card-hover);border-color:#d4af374d;transform:translateY(-4px);box-shadow:var(--shadow-lg)}.puzzle-mode-card .puzzle-mode-icon{flex-shrink:0;width:40px;height:40px;display:flex;align-items:center;justify-content:center;background:#d4af3726;border-radius:var(--radius-md);font-size:1.25rem}@media (min-width: 768px){.puzzle-mode-card .puzzle-mode-icon{width:48px;height:48px;font-size:1.5rem}}.puzzle-mode-card .puzzle-mode-content{flex:1;min-width:0}.puzzle-mode-card .puzzle-mode-content h2{font-size:1.1rem;font-weight:600;margin-bottom:var(--space-xs);color:var(--text-primary)}.puzzle-mode-card .puzzle-mode-content p{font-size:.9rem;color:var(--text-secondary);line-height:1.4;margin-bottom:var(--space-sm)}.puzzle-mode-card .puzzle-mode-stat{display:flex;align-items:center;gap:var(--space-sm)}.puzzle-mode-card .puzzle-mode-stat .stat-label{font-size:.8rem;color:var(--text-muted)}.puzzle-mode-card .puzzle-mode-stat .stat-value{font-size:1rem;font-weight:600;color:var(--accent)}.puzzle-mode-card .puzzle-mode-arrow{position:absolute;right:var(--space-md);top:50%;transform:translateY(-50%);opacity:0;transition:all var(--transition-fast)}.puzzle-mode-card .puzzle-mode-arrow:before{content:"→";font-size:1.25rem;color:var(--accent)}.game-card,.famous-game{display:flex;justify-content:space-between;align-items:center;gap:var(--space-md);padding:var(--space-md) var(--space-lg);background:#ffffff08;border-radius:var(--radius-sm)}@media (max-width: 599px){.game-card,.famous-game{flex-direction:column;align-items:flex-start;padding:var(--space-md);gap:var(--space-xs)}}.game-card .game-players,.game-card .players,.famous-game .game-players,.famous-game .players{color:var(--text-primary);flex:1;font-weight:500}.game-card .game-meta,.game-card .year,.famous-game .game-meta,.famous-game .year{color:var(--text-secondary);font-size:.875rem}.game-card .result,.famous-game .result{font-weight:600;color:var(--accent)}.profile-stat-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-lg);text-align:center}.content-section{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-lg);margin-bottom:var(--space-lg);width:100%;border-radius:var(--radius-lg)}@media (min-width: 600px){.content-section{padding:var(--space-xl)}}.content-section h2{font-size:1.35rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(212,175,55,.2)}@media (min-width: 600px){.content-section h2{font-size:1.5rem}}.content-section h3{font-size:1.1rem;color:var(--text-primary);margin:var(--space-lg) 0 var(--space-md);display:flex;align-items:center;gap:var(--space-sm)}@media (min-width: 600px){.content-section h3{font-size:1.2rem}}.content-section p:last-child{margin-bottom:0}.content-section li{margin-bottom:var(--space-sm);padding:var(--space-sm) 0;border-bottom:1px solid rgba(255,255,255,.05)}.content-section li:last-child{border-bottom:none}.content-section li strong{color:var(--text-primary)}.category-section,.opening-category,.theme-category{margin-bottom:var(--space-xxl)}@media (max-width: 599px){.category-section:first-child,.opening-category:first-child,.theme-category:first-child{padding-top:var(--space-md)}}@media (min-width: 600px){.category-title{font-size:1.5rem;border-bottom-width:2px}}.features-grid{display:grid;grid-template-columns:1fr;gap:var(--space-lg)}@media (min-width: 480px){.features-grid{grid-template-columns:repeat(auto-fit,minmax(250px,1fr))}}.openings-grid{display:grid;grid-template-columns:1fr;gap:var(--space-md);margin-top:var(--space-lg)}@media (min-width: 480px){.openings-grid{grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}}@media (min-width: 600px){.openings-grid{margin-top:var(--space-xl)}}.theme-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-md)}@media (min-width: 600px){.theme-grid{grid-template-columns:repeat(auto-fill,minmax(140px,1fr))}}.two-column-grid{display:grid;grid-template-columns:1fr;gap:var(--space-lg);width:100%;margin-bottom:var(--space-lg)}@media (min-width: 768px){.two-column-grid{grid-template-columns:1fr 1fr}}.two-column-grid .content-section{margin-bottom:0}.pros-cons-grid{display:grid;grid-template-columns:1fr;gap:var(--space-lg)}@media (min-width: 600px){.pros-cons-grid{grid-template-columns:1fr 1fr}}.profile-stats-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-md);margin-bottom:var(--space-xl)}@media (min-width: 600px){.profile-stats-grid{grid-template-columns:repeat(auto-fit,minmax(150px,1fr))}}.related-openings-grid{display:grid;grid-template-columns:1fr;gap:var(--space-md)}@media (min-width: 600px){.related-openings-grid{grid-template-columns:repeat(auto-fill,minmax(200px,1fr))}}.elo-slider-container{background:var(--bg-card);border-radius:var(--radius-md);padding:var(--space-lg);margin-bottom:var(--space-xl);border:1px solid rgba(255,255,255,.1)}@media (min-width: 600px){.elo-slider-container{padding:var(--space-xl)}}.elo-value{font-size:1.5rem;font-weight:700;color:var(--accent);min-width:80px;text-align:center;font-variant-numeric:tabular-nums}@media (min-width: 600px){.elo-value{font-size:2rem}}.modal{position:fixed;top:0;left:0;width:100%;height:100%;background:#000c;display:flex;align-items:center;justify-content:center;z-index:1000}.modal.hidden{display:none}.modal-content{background:var(--bg-card);padding:var(--space-xl);border-radius:var(--radius-lg);text-align:center;max-width:90%;width:320px;backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border:1px solid rgba(255,255,255,.1)}.modal-content h3{margin-bottom:var(--space-md)}.modal-content p{color:var(--text-secondary);margin-bottom:var(--space-xl)}.modal-buttons{display:flex;gap:var(--space-md)}.modal-buttons .btn{flex:1}.promotion-dialog{position:fixed;top:0;right:0;bottom:0;left:0;background:#000c;display:flex;align-items:center;justify-content:center;z-index:1000}.promotion-options{background:var(--bg-card);border-radius:var(--radius-md);padding:var(--space-lg);display:flex;gap:var(--space-md)}.promotion-piece{width:60px;height:60px;display:flex;align-items:center;justify-content:center;font-size:2.5rem;background:var(--board-light);border-radius:var(--radius-sm);cursor:pointer;transition:var(--transition-fast);border:2px solid transparent}.promotion-piece:hover{border-color:var(--accent);transform:scale(1.1)}.puzzle-status-overlay{position:absolute;top:0;left:0;right:0;bottom:0;background:#000000d9;flex-direction:column;display:flex;align-items:center;justify-content:center;gap:var(--space-md);z-index:10;border-radius:var(--radius-md)}.status-message{font-size:1.5rem;font-weight:700;color:var(--accent)}.status-details{color:var(--text-secondary);text-align:center}.spinner{width:40px;height:40px;border:3px solid rgba(255,255,255,.1);border-top-color:var(--accent);border-radius:var(--radius-full);animation:spin 1s linear infinite}.spinner.large{width:60px;height:60px;border-width:4px}.spinner.small{width:20px;height:20px;border-width:2px}.loading-spinner{width:48px;height:48px;border:4px solid rgba(212,175,55,.2);border-top-color:#d4af37;border-radius:50%;animation:spin 1s linear infinite;margin-bottom:16px}.puzzle-loading,.board-loading,.leaderboard-loading{flex-direction:column;display:flex;align-items:center;justify-content:center;gap:var(--space-md);padding:var(--space-xxl);color:var(--text-muted)}.board-loading{grid-column:1/-1}.app-loading{flex-direction:column;display:flex;align-items:center;justify-content:center;min-height:100vh;background:#0a0a1a;color:#fff;font-family:Inter,sans-serif}.eco-badge{display:inline-block;background:var(--accent);color:var(--bg-dark);padding:4px 12px;border-radius:var(--radius-sm);font-size:.875rem;font-weight:600;margin-top:var(--space-sm)}.puzzle-theme-tag,.theme-tag{background:#d4af3733;color:var(--accent);padding:2px 8px;border-radius:var(--radius-sm);font-size:.75rem}.puzzle-preview-badge .badge-icon{font-size:1.25rem}.puzzle-preview-badge .badge-text{color:var(--text-secondary);font-size:.9rem}.puzzle-themes{display:flex;flex-wrap:wrap;gap:var(--space-xs);justify-content:center}.board-container{position:relative;--board-size: min(92vw, calc(100svh - 280px) );--piece-size: calc(var(--board-size) / 9);width:var(--board-size);height:var(--board-size);flex-shrink:0;flex-grow:0}@media (min-width: 900px){.board-container{--board-size: min(85vw, calc(100vh - 280px) , 600px)}}@supports not (height: 100svh){.board-container{--board-size: min(92vw, calc(100vh - 320px) )}}.board{display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);width:100%;height:100%;border-radius:var(--radius-sm);overflow:hidden;box-shadow:var(--shadow-lg),var(--board-glow)}.puzzle-board{--piece-size: calc(min(95vw, 400px) / 9);display:grid;grid-template-columns:repeat(8,1fr);width:min(95vw,400px);aspect-ratio:1;border-radius:var(--radius-md);overflow:hidden;box-shadow:var(--shadow-lg),var(--board-glow);border:3px solid var(--accent-dark);transition:box-shadow var(--transition-fast)}@media (min-width: 600px){.puzzle-board{--piece-size: calc(min(85vw, 480px) / 9);width:min(85vw,480px)}}.puzzle-board.your-turn{box-shadow:var(--shadow-lg),var(--board-glow),var(--board-turn-glow)}.puzzle-board-container{position:relative;display:flex;flex-direction:column;align-items:center;gap:var(--space-md);transition:var(--transition-fast)}.animated-board-container{position:relative;width:100%;max-width:300px;--piece-size: clamp(32px, 6vw, 48px);aspect-ratio:1;perspective:1000px}@media (min-width: 900px){.animated-board-container{max-width:400px;--piece-size: clamp(36px, 7vw, 56px)}}@media (min-width: 900px){.demo-board{transform:rotateX(5deg) rotateY(-5deg)}.demo-board:hover{transform:rotateX(0) rotateY(0)}}@media (max-width: 899px){.demo-board{transform:none}}.result-board-container{--piece-size: calc(min(70vw, 280px) / 9);width:min(70vw,280px);aspect-ratio:1}@media (min-width: 768px){.result-board-container{--piece-size: calc(min(80vw, 350px) / 9);width:min(80vw,350px)}}.result-board .piece{font-size:var(--piece-size);cursor:default}.opening-board{--piece-size: clamp(2rem, 5vw, 2.75rem);display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);width:100%;max-width:400px;aspect-ratio:1;border-radius:var(--radius-sm);overflow:hidden;box-shadow:var(--shadow-lg),var(--board-glow)}.opening-animation-container{display:flex;flex-direction:column;align-items:center;gap:var(--space-sm)}.opening-controls{display:flex;gap:var(--space-sm);justify-content:center}.move-indicator{font-size:.875rem;color:var(--text-secondary)}.move-explanation{background:#d4af371a;border-left:3px solid var(--accent);padding:var(--space-sm) var(--space-md);border-radius:0 var(--radius-sm) var(--radius-sm) 0;margin-top:var(--space-md);width:100%;max-width:400px;text-align:center}@media (min-width: 600px){.move-explanation{padding:var(--space-md)}}.game-container{grid-area:game;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-xs);width:100%;max-height:calc(100vh - 90px);padding-bottom:60px}@media (min-width: 900px){.game-container{padding-bottom:0}}.game-sidebar{position:fixed;bottom:0;left:0;right:0;width:100%;display:flex;flex-direction:row;justify-content:center;padding:var(--space-sm);background:var(--bg-darker);border-top:1px solid rgba(255,255,255,.1);z-index:100;gap:var(--space-sm)}@media (min-width: 900px){.game-sidebar{grid-area:sidebar;position:static;flex-direction:column;gap:var(--space-md);width:160px;align-self:center;background:transparent;border-top:none;padding:0}}#game-screen .game-controls{display:flex;flex-direction:row;justify-content:center;width:auto;gap:var(--space-sm)}@media (min-width: 900px){#game-screen .game-controls{flex-direction:column;width:100%}}#game-screen .game-controls .btn{width:auto;flex:none}@media (min-width: 900px){#game-screen .game-controls .btn{width:100%}}.puzzle-controls{display:flex;flex-wrap:wrap;gap:var(--space-md);width:100%;justify-content:center}.puzzle-controls .btn,.puzzle-controls .puzzle-btn{flex:1;min-width:calc(50% - var(--space-sm))}@media (min-width: 600px){.puzzle-controls .btn,.puzzle-controls .puzzle-btn{flex:0 1 auto;min-width:120px}}.piece{line-height:1;-webkit-user-select:none;user-select:none;text-shadow:1px 1px 2px rgba(0,0,0,.5)}.piece.white{color:var(--piece-white);filter:drop-shadow(1px 1px 0 rgba(0,0,0,.8)) drop-shadow(-1px -1px 0 rgba(0,0,0,.8)) drop-shadow(1px -1px 0 rgba(0,0,0,.8)) drop-shadow(-1px 1px 0 rgba(0,0,0,.8))}.piece.black{color:var(--piece-black)}.piece.captured{animation:capture .3s ease-out forwards}.piece.promoted{animation:promote .5s ease-out}.piece.just-moved{animation:justMoved .3s ease-out}.piece.moving{animation:pieceMove .3s ease-out}.piece{font-size:var(--piece-size, 3rem);cursor:grab;z-index:1;transition:transform var(--transition-normal)}.piece.dragging{cursor:grabbing;transform:scale(1.2);z-index:100;opacity:.5}.demo-piece{line-height:1;-webkit-user-select:none;user-select:none;text-shadow:1px 1px 2px rgba(0,0,0,.5)}.demo-piece.white{color:var(--piece-white);filter:drop-shadow(1px 1px 0 rgba(0,0,0,.8)) drop-shadow(-1px -1px 0 rgba(0,0,0,.8)) drop-shadow(1px -1px 0 rgba(0,0,0,.8)) drop-shadow(-1px 1px 0 rgba(0,0,0,.8))}.demo-piece.black{color:var(--piece-black)}.demo-piece.captured{animation:capture .3s ease-out forwards}.demo-piece.promoted{animation:promote .5s ease-out}.demo-piece.just-moved{animation:justMoved .3s ease-out}.demo-piece.moving{animation:pieceMove .3s ease-out}.demo-piece{position:absolute;top:0;left:0;right:0;bottom:0;display:flex;align-items:center;justify-content:center;font-size:var(--piece-size, clamp(36px, 7vw, 64px));transition:all .5s ease-in-out}.opening-piece{line-height:1;-webkit-user-select:none;user-select:none;text-shadow:1px 1px 2px rgba(0,0,0,.5)}.opening-piece.white{color:var(--piece-white);filter:drop-shadow(1px 1px 0 rgba(0,0,0,.8)) drop-shadow(-1px -1px 0 rgba(0,0,0,.8)) drop-shadow(1px -1px 0 rgba(0,0,0,.8)) drop-shadow(-1px 1px 0 rgba(0,0,0,.8))}.opening-piece.black{color:var(--piece-black)}.opening-piece.captured{animation:capture .3s ease-out forwards}.opening-piece.promoted{animation:promote .5s ease-out}.opening-piece.just-moved{animation:justMoved .3s ease-out}.opening-piece.moving{animation:pieceMove .3s ease-out}.opening-piece{font-size:var(--piece-size, 2.5rem);transition:transform .2s ease}.puzzle-board .piece{line-height:1;-webkit-user-select:none;user-select:none;text-shadow:1px 1px 2px rgba(0,0,0,.5)}.puzzle-board .piece.white{color:var(--piece-white);filter:drop-shadow(1px 1px 0 rgba(0,0,0,.8)) drop-shadow(-1px -1px 0 rgba(0,0,0,.8)) drop-shadow(1px -1px 0 rgba(0,0,0,.8)) drop-shadow(-1px 1px 0 rgba(0,0,0,.8))}.puzzle-board .piece.black{color:var(--piece-black)}.puzzle-board .piece.captured{animation:capture .3s ease-out forwards}.puzzle-board .piece.promoted{animation:promote .5s ease-out}.puzzle-board .piece.just-moved{animation:justMoved .3s ease-out}.puzzle-board .piece.moving{animation:pieceMove .3s ease-out}.puzzle-board .piece{font-size:var(--piece-size);pointer-events:none}.player-captured{display:flex;align-items:center;gap:4px;min-height:18px}.captured-pieces{display:flex;flex-wrap:wrap;gap:1px}.captured-piece{font-size:1rem;opacity:1;line-height:1}.captured-piece+.captured-piece{margin-left:-2px}.material-advantage{font-size:.75rem;font-weight:600;color:var(--text-secondary);margin-left:4px}.material-advantage.ahead{color:var(--success, #4ade80)}.chess-board .square.can-move{cursor:pointer}.chess-board .square.can-move .piece{cursor:grab}.chess-board .square.can-move .piece:active{cursor:grabbing}.square{display:flex;align-items:center;justify-content:center;position:relative;cursor:pointer;transition:background-color var(--transition-fast);aspect-ratio:1}.square.light{background-color:var(--board-light)}.square.dark{background-color:var(--board-dark)}.square.selected{background-color:var(--board-selected)!important}.square.last-move{background-color:var(--board-highlight)!important}.square.legal-move:after{content:"";position:absolute;width:30%;height:30%;background:var(--board-legal);border-radius:var(--radius-full)}.square.legal-capture:after{content:"";position:absolute;width:90%;height:90%;border:4px solid var(--board-capture);border-radius:var(--radius-full);background:transparent}.square.check{background:var(--board-check)!important}.square.can-move{animation:glow 1s ease-in-out infinite}.opening-square{display:flex;align-items:center;justify-content:center;aspect-ratio:1;transition:background-color .3s ease;position:relative}.opening-square.light{background-color:var(--board-light)}.opening-square.dark{background-color:var(--board-dark)}.opening-square.highlight{background-color:#d4af3780!important}.puzzle-board .square{aspect-ratio:1;display:flex;align-items:center;justify-content:center;cursor:pointer;transition:var(--transition-fast);position:relative}.puzzle-board .square.light{background:var(--board-light)}.puzzle-board .square.dark{background:var(--board-dark)}.puzzle-board .square.selected{background:var(--board-selected)!important}.puzzle-board .square.last-move{background:var(--board-highlight)!important}.puzzle-board .square.legal-move:after{content:"";position:absolute;width:30%;height:30%;border-radius:50%;background:var(--board-legal)}.puzzle-board .square.legal-capture:after{content:"";position:absolute;width:90%;height:90%;border-radius:50%;border:4px solid var(--board-capture);background:transparent}.puzzle-board .square.hint-piece,.puzzle-board .square.hint-from{animation:hint-pulse .8s ease-in-out infinite;background-color:#00ff9666!important}.puzzle-board .square.hint-target,.puzzle-board .square.hint-to{box-shadow:inset 0 0 0 4px #00ff96;background-color:#00ff9633!important}.square.puzzle-hint{background-color:#64c8ff80!important;animation:hintPulse 1s ease-in-out infinite}.square.puzzle-correct{background-color:#27ae6080!important}.square.puzzle-wrong{background-color:#c0392b80!important;animation:wrongShake .3s ease-in-out}.coord-label{position:absolute;font-size:.65rem;font-weight:600;font-family:Inter,sans-serif;line-height:1;pointer-events:none;-webkit-user-select:none;user-select:none}.rank-label{top:2px;left:3px}.file-label{bottom:2px;right:3px}.coord-label.on-light{color:var(--board-dark)}.coord-label.on-dark{color:var(--board-light)}.square .file-label{position:absolute;bottom:2px;right:4px;font-size:10px;font-weight:600;pointer-events:none}.square .rank-label{position:absolute;top:2px;left:4px;font-size:10px;font-weight:600;pointer-events:none}.square.light .file-label,.square.light .rank-label{color:var(--board-dark)}.square.dark .file-label,.square.dark .rank-label{color:var(--board-light)}.promotion-modal{position:absolute;top:0;left:0;right:0;bottom:0;background:#000c;display:flex;align-items:center;justify-content:center;z-index:200;border-radius:var(--radius-sm)}.promotion-modal.hidden{display:none}.promotion-pieces{display:flex;gap:var(--space-md);background:var(--bg-card);padding:var(--space-lg);border-radius:var(--radius-md)}.promotion-piece{font-size:3rem;cursor:pointer;padding:var(--space-sm);border-radius:var(--radius-sm);transition:all var(--transition-fast)}.promotion-piece:hover{background:var(--bg-card-hover);transform:scale(1.1)}.home-main{padding-top:60px;width:100%;flex:1}#home-screen.active{display:flex!important;flex-direction:column;overflow-y:auto;justify-content:flex-start!important;align-items:stretch!important;min-height:100vh;height:100vh;padding:0}.hero-section{min-height:calc(100vh - 60px);padding:var(--space-xxl) var(--space-lg);display:flex;align-items:center}.hero-container{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-xxl);max-width:1200px;margin:0 auto;width:100%;align-items:center}@media (max-width: 767px){.hero-container{grid-template-columns:1fr;gap:var(--space-xl)}}.hero-content{display:flex;flex-direction:column;gap:var(--space-lg);align-items:flex-start;text-align:left}@media (max-width: 767px){.hero-content{align-items:center;text-align:center;order:2}}.hero-title{font-size:3.5rem;font-weight:700;line-height:1.1;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}@media (max-width: 767px){.hero-title{font-size:2.5rem}}@media (max-width: 479px){.hero-title{font-size:2rem}}.hero-subtitle{font-size:1.25rem;color:var(--text-secondary);max-width:400px;line-height:1.6}@media (max-width: 767px){.hero-subtitle{max-width:100%}}@media (max-width: 479px){.hero-subtitle{font-size:1rem}}.hero-visual{display:flex;justify-content:center;align-items:center}@media (max-width: 767px){.hero-visual{order:1}}.rating-display{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs);padding:var(--space-md) var(--space-xl);background:linear-gradient(135deg,#d4af3726,#141428e6);border:1px solid rgba(212,175,55,.3);border-radius:var(--radius-lg);margin-bottom:var(--space-md)}@media (max-width: 767px){.rating-display{padding:var(--space-sm) var(--space-lg)}}.rating-value{font-size:2.5rem;font-weight:700;color:var(--accent);font-family:Roboto Mono,monospace;text-shadow:0 0 20px rgba(212,175,55,.4)}@media (max-width: 479px){.rating-value{font-size:2rem}}.rating-label{font-size:.875rem;color:var(--text-secondary);text-transform:uppercase;letter-spacing:.1em}.time-control-panel{display:flex;flex-wrap:wrap;gap:var(--space-lg);padding:var(--space-lg);background:#0000004d;border-radius:var(--radius-lg);border:1px solid rgba(255,255,255,.1);margin-bottom:var(--space-lg);width:100%;max-width:400px}@media (max-width: 767px){.time-control-panel{justify-content:center;max-width:100%}}@media (max-width: 479px){.time-control-panel{gap:var(--space-md);padding:var(--space-md)}}.time-category{display:flex;flex-direction:column;gap:var(--space-sm);flex:1;min-width:100px}.time-category h4{font-size:.875rem;font-weight:600;color:var(--text-secondary);display:flex;align-items:center;gap:var(--space-xs);margin:0}@media (max-width: 479px){.time-category h4{font-size:.75rem}}.tc-icon{font-size:1rem}.time-options{display:flex;flex-wrap:wrap;gap:var(--space-xs)}.time-btn{padding:var(--space-xs) var(--space-sm);font-size:.875rem;font-weight:500;background:#ffffff0d;border:1px solid rgba(255,255,255,.15);border-radius:var(--radius-sm);color:var(--text-secondary);cursor:pointer;transition:all var(--transition-fast)}.time-btn:hover{background:#ffffff1a;border-color:#ffffff40;color:var(--text-primary)}.time-btn.selected{background:#d4af3733;border-color:var(--accent);color:var(--accent);font-weight:600}@media (max-width: 479px){.time-btn{font-size:.75rem;padding:var(--space-xs)}}.play-buttons{display:flex;flex-direction:column;gap:var(--space-md);width:100%;max-width:320px}@media (max-width: 767px){.play-buttons{align-items:center}}.play-buttons .btn{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs);width:100%}.btn-main{font-size:1.125rem;font-weight:600}.btn-sub{font-size:.75rem;opacity:.7;font-weight:400}.rating-result{display:flex;align-items:center;justify-content:center;gap:var(--space-md);margin:var(--space-lg) 0;padding:var(--space-md) var(--space-xl);background:#0000004d;border-radius:var(--radius-md);font-family:Roboto Mono,monospace}.rating-before,.rating-after{font-size:1.5rem;font-weight:600;color:var(--text-primary)}@media (max-width: 479px){.rating-before,.rating-after{font-size:1.25rem}}.rating-arrow{font-size:1.25rem;color:var(--text-secondary)}.rating-change{font-size:1.25rem;font-weight:700;padding:var(--space-xs) var(--space-sm);border-radius:var(--radius-sm)}@media (max-width: 479px){.rating-change{font-size:1rem}}.rating-gain{color:#27ae60;background:#27ae6026}.rating-loss{color:#e74c3c;background:#e74c3c26}.animated-board-container{position:relative;width:100%;max-width:400px;aspect-ratio:1;perspective:1000px}@media (max-width: 767px){.animated-board-container{max-width:300px}}.demo-board{display:grid;grid-template-columns:repeat(8,12.5%);grid-template-rows:repeat(8,12.5%);width:100%;height:100%;border-radius:var(--radius-md);overflow:hidden;box-shadow:var(--shadow-lg),0 0 60px #d4af3733;transform:rotateX(5deg) rotateY(-5deg);transition:transform var(--transition-slow)}.demo-board:hover{transform:rotateX(0) rotateY(0)}@media (max-width: 767px){.demo-board{transform:none}}.demo-square{position:relative;aspect-ratio:1;min-width:0;min-height:0}.demo-square.light{background-color:var(--board-light)}.demo-square.dark{background-color:var(--board-dark)}.demo-square.highlight{background-color:#d4af3780!important}.feature-section{padding:var(--space-xxl) var(--space-lg);width:100%}@media (min-width: 600px){.feature-section{padding:60px var(--space-lg)}}@media (min-width: 768px){.feature-section{padding:80px var(--space-lg)}}.feature-section--dark{background:var(--bg-darker)}.feature-section__container{display:grid;grid-template-columns:1fr;gap:var(--space-xl);max-width:1100px;margin:0 auto;width:100%;align-items:center}.feature-section__container .feature-section__visual{order:1}.feature-section__container .feature-section__text{order:2}@media (min-width: 768px){.feature-section__container{grid-template-columns:1fr 1fr;gap:var(--space-xxl)}.feature-section__container .feature-section__text{order:1}.feature-section__container .feature-section__visual{order:2}}@media (min-width: 768px){.feature-section__container--reversed .feature-section__text{order:2}.feature-section__container--reversed .feature-section__visual{order:1}}.feature-section__text{display:flex;flex-direction:column;gap:var(--space-lg);text-align:center}@media (min-width: 768px){.feature-section__text{text-align:left}}.feature-section__title{font-size:2rem;font-weight:700;color:var(--text-primary);line-height:1.2}@media (min-width: 600px){.feature-section__title{font-size:2.5rem}}.feature-section__description{font-size:1rem;color:var(--text-secondary);line-height:1.7;max-width:480px;margin:0 auto}@media (min-width: 768px){.feature-section__description{font-size:1.125rem;margin:0}}.feature-section__cta{align-self:center}@media (min-width: 768px){.feature-section__cta{align-self:flex-start}}.feature-section__visual{display:flex;align-items:center;justify-content:center}.puzzle-preview{display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);width:100%;max-width:260px;aspect-ratio:1;border-radius:var(--radius-md);overflow:hidden;box-shadow:var(--shadow-lg),var(--board-glow)}@media (min-width: 600px){.puzzle-preview{max-width:300px}}@media (min-width: 768px){.puzzle-preview{max-width:340px}}.bot-avatars-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-md);width:100%;max-width:300px}@media (min-width: 600px){.bot-avatars-grid{max-width:360px}}.bot-avatar-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);display:flex;align-items:center;justify-content:center;flex-direction:column;gap:var(--space-sm);padding:var(--space-lg) var(--space-md);border-radius:var(--radius-lg);text-align:center;transition:transform var(--transition-fast),box-shadow var(--transition-fast)}.bot-avatar-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}.bot-avatar-card__icon{width:64px;height:64px;border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;font-size:2rem;line-height:1;-webkit-user-select:none;user-select:none;text-shadow:1px 1px 2px rgba(0,0,0,.5)}@media (min-width: 600px){.bot-avatar-card__icon{width:72px;height:72px;font-size:2.25rem}}.bot-avatar-card__name{font-size:.875rem;font-weight:600;color:var(--text-primary)}.bot-avatar-card__rating{font-size:.75rem;font-weight:500;color:var(--text-secondary);font-family:Roboto Mono,monospace}.bot-avatar-card--beginner{border-color:#27ae604d}.bot-avatar-card--beginner .bot-avatar-card__icon{background:#27ae6033;color:#27ae60}.bot-avatar-card--intermediate{border-color:#3498db4d}.bot-avatar-card--intermediate .bot-avatar-card__icon{background:#3498db33;color:#3498db}.bot-avatar-card--advanced{border-color:#f39c124d}.bot-avatar-card--advanced .bot-avatar-card__icon{background:#f39c1233;color:#f39c12}.bot-avatar-card--master{border-color:#d4af374d}.bot-avatar-card--master .bot-avatar-card__icon{background:#d4af3733;color:var(--accent)}.opening-cards-stack{position:relative;width:260px;height:200px}@media (min-width: 600px){.opening-cards-stack{width:300px;height:220px}}.opening-card-preview{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);position:absolute;width:100%;padding:var(--space-lg) var(--space-xl);border-radius:var(--radius-lg);display:flex;flex-direction:column;gap:var(--space-sm);transition:transform var(--transition-slow)}.opening-card-preview--front{bottom:0;left:0;z-index:3;border-color:#d4af374d;background:var(--bg-card)}.opening-card-preview--back1{bottom:20px;left:12px;z-index:2;transform:rotate(3deg);opacity:.85}.opening-card-preview--back2{bottom:40px;left:24px;z-index:1;transform:rotate(6deg);opacity:.65}.opening-card-preview__name{font-size:1.125rem;font-weight:700;color:var(--text-primary)}.opening-card-preview__moves{font-size:.875rem;color:var(--accent);font-family:Roboto Mono,monospace;letter-spacing:.02em}.opening-cards-stack:hover .opening-card-preview--back1{transform:rotate(5deg) translate(8px)}.opening-cards-stack:hover .opening-card-preview--back2{transform:rotate(10deg) translate(16px)}.vs-visual{position:relative;display:flex;align-items:center;justify-content:center;gap:var(--space-xl);padding:var(--space-xl);width:100%;max-width:340px}.vs-visual__player{width:100px;height:100px;border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;position:relative;z-index:2}@media (min-width: 600px){.vs-visual__player{width:120px;height:120px}}.vs-visual__player--left{background:linear-gradient(135deg,#d4af3740,#d4af370d);border:2px solid rgba(212,175,55,.4);box-shadow:0 0 30px #d4af3726}.vs-visual__player--right{background:linear-gradient(135deg,#6482dc40,#6482dc0d);border:2px solid rgba(100,130,220,.4);box-shadow:0 0 30px #6482dc26}.vs-visual__piece{font-size:2.5rem;line-height:1;-webkit-user-select:none;user-select:none;color:var(--text-primary);text-shadow:1px 1px 2px rgba(0,0,0,.5)}@media (min-width: 600px){.vs-visual__piece{font-size:3rem}}.vs-visual__badge{position:absolute;z-index:3;top:50%;left:50%;transform:translate(-50%,-50%);width:44px;height:44px;border-radius:var(--radius-full);background:linear-gradient(135deg,var(--accent),var(--accent-dark));color:#1a1a2e;font-size:.875rem;font-weight:800;display:flex;align-items:center;justify-content:center;letter-spacing:.05em;box-shadow:0 0 20px #d4af3766}.vs-visual__line{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:70%;height:2px;background:linear-gradient(90deg,#d4af374d,#d4af371a 40%,#6482dc1a 60%,#6482dc4d);z-index:1}.about-section{padding:var(--space-xxl) var(--space-lg);background:var(--bg-darker)}.about-container{max-width:900px;margin:0 auto}.about-title{font-size:1.75rem;font-weight:700;color:var(--accent);margin-bottom:var(--space-xl);text-align:center}@media (max-width: 479px){.about-title{font-size:1.5rem}}.about-text p{color:var(--text-secondary);line-height:1.8;margin-bottom:var(--space-md);font-size:1rem}.about-text p:last-child{margin-bottom:0}.about-text p a{color:var(--accent);text-decoration:none}.about-text p a:hover{text-decoration:underline}.final-cta{padding:var(--space-xxl) var(--space-lg);text-align:center;background:linear-gradient(135deg,rgba(212,175,55,.15),var(--bg-darker));position:relative;overflow:hidden}.final-cta:before{content:"";position:absolute;top:-50%;left:-50%;width:200%;height:200%;background:radial-gradient(circle,rgba(212,175,55,.1) 0%,transparent 60%);animation:cta-glow 4s ease-in-out infinite;pointer-events:none}@keyframes cta-glow{0%,to{opacity:.5;transform:scale(1)}50%{opacity:1;transform:scale(1.1)}}.final-cta__title{font-size:2.5rem;font-weight:700;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:var(--space-md);position:relative}@media (max-width: 767px){.final-cta__title{font-size:2rem}}@media (max-width: 479px){.final-cta__title{font-size:1.5rem}}.final-cta__subtitle{font-size:1.25rem;color:var(--text-secondary);margin-bottom:var(--space-xl);position:relative}@media (max-width: 479px){.final-cta__subtitle{font-size:1rem}}.btn-cta{font-size:1.25rem;padding:var(--space-md) var(--space-xl)}@media (max-width: 479px){.btn-cta{font-size:1rem;padding:var(--space-md) var(--space-lg)}}.btn-xlarge{font-size:1.5rem;padding:var(--space-lg) var(--space-xxl)}@media (max-width: 479px){.btn-xlarge{font-size:1.125rem;padding:var(--space-md) var(--space-xl)}}.logo-section{margin-bottom:var(--space-xxl)}.logo-icon{font-size:80px;margin-bottom:var(--space-md);animation:float 3s ease-in-out infinite;text-shadow:0 0 30px rgba(212,175,55,.5)}@media (max-width: 479px){.logo-icon{font-size:60px}}.title{font-size:2rem;font-weight:700;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:var(--space-sm)}@media (max-width: 479px){.title{font-size:1.5rem}}.subtitle{color:var(--text-secondary);font-size:1rem}.time-select-screen{background:var(--bg-primary);padding:var(--space-lg);min-height:100vh}.time-select-screen.active{display:flex;align-items:center;justify-content:center}.time-select-container{max-width:600px;width:100%;display:flex;flex-direction:column;gap:var(--space-xl);position:relative}.time-select-container .back-btn{position:absolute;top:0;left:0;background:transparent;border:none;color:var(--text-secondary);font-size:1.5rem;cursor:pointer;padding:var(--space-sm);transition:color var(--transition-fast)}.time-select-container .back-btn:hover{color:var(--text-primary)}.time-select-header{text-align:center;margin-top:var(--space-xl)}.time-select-title{font-size:2rem;font-weight:700;color:var(--text-primary);margin-bottom:var(--space-xs)}.time-select-subtitle{color:var(--accent);font-size:1.125rem;font-weight:500}.time-select-grid{display:flex;flex-direction:column;gap:var(--space-lg)}.time-category-card{background:linear-gradient(135deg,#ffffff0d,#ffffff05);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-lg);padding:var(--space-lg);transition:border-color var(--transition-fast)}.time-category-card:hover{border-color:#fff3}.category-header{display:flex;align-items:center;gap:var(--space-sm);margin-bottom:var(--space-md)}.category-header .category-icon{font-size:1.5rem}.category-header h3{font-size:1.25rem;font-weight:600;color:var(--text-primary);margin:0}.category-header .category-desc{margin-left:auto;font-size:.875rem;color:var(--text-secondary)}.category-options{display:flex;gap:var(--space-sm);flex-wrap:wrap}.time-option-btn{flex:1;min-width:80px;padding:var(--space-md) var(--space-lg);background:#ffffff0d;border:2px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--text-primary);cursor:pointer;transition:all var(--transition-fast);display:flex;flex-direction:column;align-items:center;gap:var(--space-xs)}.time-option-btn .time-value{font-size:1.5rem;font-weight:700}.time-option-btn .time-unit{font-size:.75rem;color:var(--text-secondary);text-transform:uppercase}.time-option-btn:hover{background:#ffffff1a;border-color:#fff3}.time-option-btn.selected{background:#d4af3733;border-color:var(--accent)}.time-option-btn.selected .time-value{color:var(--accent)}.btn-play-confirm{width:100%;padding:var(--space-lg);font-size:1.25rem}@media (max-width: 479px){.time-select-screen{padding:var(--space-md)}.time-select-title{font-size:1.5rem}.category-header{flex-wrap:wrap}.category-header .category-desc{width:100%;margin-left:0;margin-top:var(--space-xs)}.time-option-btn{min-width:70px;padding:var(--space-sm) var(--space-md)}.time-option-btn .time-value{font-size:1.25rem}}#game-screen{padding:var(--space-md);padding-top:70px}#game-screen.active{display:grid!important;grid-template-columns:1fr minmax(auto,720px) 180px 1fr;grid-template-rows:auto;grid-template-areas:". game sidebar .";align-items:center;gap:var(--space-md);padding:var(--space-sm);padding-top:70px;padding-bottom:var(--space-sm);height:100vh;overflow:hidden;box-sizing:border-box}@media (max-width: 899px){#game-screen.active{display:flex!important;flex-direction:column;justify-content:flex-start;align-items:center;padding-top:60px;padding-bottom:var(--space-md);gap:var(--space-xs);height:auto;min-height:100vh;min-height:100svh;overflow:auto}}.game-container{grid-area:game;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-xs);width:100%;max-height:calc(100vh - 90px);padding-bottom:0}@media (max-width: 899px){.game-container{max-width:600px;flex:none;padding:var(--space-xs)}}.player-info{display:flex;align-items:center;gap:var(--space-md);width:100%;padding:var(--space-sm) var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);border:2px solid transparent;box-sizing:border-box}.player-info.active{border-color:var(--accent);box-shadow:0 0 15px #d4af374d}@media (min-width: 480px){.player-info{padding:var(--space-xs) var(--space-sm)}}.player-avatar{width:40px;height:40px;display:flex;align-items:center;justify-content:center;font-size:1.5rem;background:var(--bg-darker);border-radius:var(--radius-sm)}@media (min-width: 480px){.player-avatar{width:32px;height:32px;font-size:1.25rem}}.player-details{flex:1;display:flex;flex-direction:row;align-items:center;gap:var(--space-sm);min-width:0}.player-icon{font-size:1.25rem;flex-shrink:0}.player-name-color{display:flex;flex-direction:row;align-items:baseline;gap:var(--space-xs);min-width:0}.player-name-color .name{font-weight:600;font-size:.9rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.player-name-color .color{font-size:.75rem;color:var(--text-secondary);white-space:nowrap}.player-timer{font-size:1.25rem;font-weight:700;font-variant-numeric:tabular-nums;padding:var(--space-xs) var(--space-sm);background:var(--bg-darker);border-radius:var(--radius-sm);min-width:70px;text-align:center}.player-timer.warning{color:var(--warning)}.player-timer.danger{color:var(--danger);animation:pulse .5s ease-in-out infinite}@media (min-width: 480px){.player-timer{font-size:1rem;min-width:60px}}.board-container{position:relative;--board-size: min(85vw, calc(100vh - 280px) , 600px);width:var(--board-size);height:var(--board-size);flex-shrink:0;flex-grow:0}@media (min-width: 900px){.board-container{--board-size: min(92vw, calc(100svh - 280px) );aspect-ratio:1}@supports not (height: 100svh){.board-container{--board-size: min(92vw, calc(100vh - 320px) )}}}.game-controls{display:flex;gap:var(--space-md);width:100%}.game-controls .btn{flex:1}#game-screen .game-controls{display:flex;flex-direction:column;justify-content:center;align-items:center;gap:var(--space-sm);width:100%}#game-screen .game-controls .btn{width:100%}@media (max-width: 899px){#game-screen .game-controls{flex-direction:row}#game-screen .game-controls .btn{width:auto;flex:none}}.game-sidebar{grid-area:sidebar;display:flex;flex-direction:column;align-items:center;gap:var(--space-md);width:160px;align-self:center}@media (max-width: 899px){.game-sidebar{width:auto;flex-direction:column;gap:var(--space-sm)}}.game-status{position:fixed;bottom:var(--space-lg);left:50%;transform:translate(-50%);background:var(--bg-card);padding:var(--space-sm) var(--space-lg);border-radius:var(--radius-lg);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);animation:slideUp .3s ease-out}.game-status.hidden{display:none}@keyframes slideUp{0%{opacity:0;transform:translate(-50%) translateY(20px)}to{opacity:1;transform:translate(-50%) translateY(0)}}#result-screen.active{display:flex!important;flex-direction:column;justify-content:flex-start;align-items:center;padding:var(--space-md);padding-top:var(--space-lg);gap:var(--space-md);overflow-y:auto}.result-container{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);max-width:400px;width:100%}.result-content{display:flex;flex-direction:column;align-items:center;gap:var(--space-lg);padding:var(--space-xl) var(--space-md)}.result-header{text-align:center}.result-icon{font-size:3rem;margin-bottom:0}.result-title{font-size:1.75rem;font-weight:700;margin-bottom:0;margin-top:calc(-1 * var(--space-sm))}.result-title.victory{color:var(--accent)}.result-title.defeat{color:var(--danger)}.result-title.draw{color:var(--text-secondary)}.result-reason{color:var(--text-secondary);font-size:.9rem;margin-top:calc(-1 * var(--space-sm))}.rematch-status{color:var(--text-secondary);font-size:.9rem;margin-top:var(--space-sm);padding:var(--space-sm) var(--space-md);background:#ffffff0d;border-radius:var(--radius-sm)}.result-content .button-group{margin-top:var(--space-sm)}.result-board-container{width:min(80vw,350px);aspect-ratio:1}@media (max-height: 700px){.result-board-container{width:min(70vw,280px)}}.result-board{width:100%;height:100%;pointer-events:none}.result-board .piece{font-size:calc(min(80vw,350px) / 9);cursor:default}@media (max-height: 700px){.result-board .piece{font-size:calc(min(70vw,280px) / 9)}}.result-stat{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs)}.result-label{font-size:.8rem;color:var(--text-muted)}.result-value{font-size:1.1rem;font-weight:600;color:var(--text-primary)}.result-value.positive{color:var(--success)}.result-value.negative{color:var(--danger)}.puzzle-result-box{margin-bottom:var(--space-xl)}.puzzle-result-box .result-icon{font-size:5rem}.puzzle-result-box .result-title{color:var(--success)}.puzzle-result-box.failed .result-title{color:var(--danger)}.puzzle-result-box.failed .result-icon:before{content:"😔"}.result-rating{color:var(--accent);font-size:.9rem;margin-top:var(--space-sm)}.matchmaking-box{display:flex;flex-direction:column;align-items:center;gap:var(--space-lg);padding:var(--space-xxl)}.matchmaking-status{color:var(--text-secondary)}.matchmaking-timer{font-size:1.25rem;font-weight:600;color:var(--accent);font-variant-numeric:tabular-nums}.invite-section.hidden{display:none}.invite-code-box{display:flex;align-items:center;justify-content:center;gap:var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);padding:var(--space-lg);margin-bottom:var(--space-xl)}#invite-code{font-size:2rem;font-weight:700;letter-spacing:.3em;font-family:monospace;color:var(--accent)}.btn-copy{background:none;border:none;font-size:1.5rem;cursor:pointer;padding:var(--space-sm);opacity:.7;transition:opacity var(--transition-fast)}.btn-copy:hover{opacity:1}.share-buttons{display:none;gap:var(--space-sm);justify-content:center;margin-bottom:var(--space-lg);flex-wrap:wrap}@media (hover: none) and (pointer: coarse){.share-buttons{display:flex}}.btn-share{display:inline-flex;align-items:center;gap:var(--space-sm);padding:var(--space-sm) var(--space-md);font-size:.9rem;font-weight:600;border-radius:var(--radius-sm);cursor:pointer;transition:all var(--transition-fast)}.btn-share svg{flex-shrink:0}.btn-native-share{background:#25d366;color:#fff;border:none}.btn-native-share:hover{background:#20bd5a;transform:translateY(-2px);box-shadow:0 4px 12px #25d36666}.invite-input-box{display:flex;gap:var(--space-md);margin-bottom:var(--space-md)}#invite-input{flex:1;padding:var(--space-md);border:2px solid rgba(255,255,255,.1);border-radius:var(--radius-md);background:var(--bg-card);color:var(--text-primary);font-size:1.5rem;font-weight:700;letter-spacing:.2em;text-align:center;text-transform:uppercase;font-family:monospace}#invite-input:focus{outline:none;border-color:var(--accent)}#invite-input::placeholder{color:var(--text-muted)}.error-message{color:var(--danger);font-size:.875rem}.error-message.hidden{display:none}.waiting-indicator{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);color:var(--text-secondary)}#difficulty-screen.active{padding-top:calc(var(--space-md) + 60px);overflow-y:auto;justify-content:flex-start}@media (min-width: 600px){#difficulty-screen.active{padding-top:calc(var(--space-sm) + 60px);padding-bottom:var(--space-xl)}}.difficulty-layout{display:flex;gap:var(--space-xl);margin-top:var(--space-lg);align-items:flex-start;justify-content:center}@media (max-width: 700px){.difficulty-layout{flex-direction:column;align-items:center}}.difficulty-options{display:flex;flex-direction:column;gap:var(--space-md);width:280px;flex-shrink:0}@media (max-width: 700px){.difficulty-options{width:100%;max-width:320px}}.difficulty-ad{display:flex;justify-content:center;align-items:flex-start;min-width:160px}@media (max-width: 700px){.difficulty-ad{margin-top:var(--space-lg)}}.difficulty-btn{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-md) var(--space-lg);background:var(--bg-card);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition-fast);text-align:left}.difficulty-btn:hover{background:var(--bg-card-hover);border-color:var(--accent);transform:translate(4px)}.difficulty-btn:active{transform:translate(2px)}.difficulty-btn[data-level="1"]:hover{border-color:#22c55e}.difficulty-btn[data-level="2"]:hover{border-color:#3b82f6}.difficulty-btn[data-level="3"]:hover{border-color:var(--accent)}.difficulty-btn[data-level="4"]:hover{border-color:#f97316}.difficulty-btn[data-level="5"]:hover{border-color:#ef4444}.difficulty-btn[data-level="6"]:hover{border-color:#a855f7}@media (min-width: 480px){.difficulty-btn{padding:var(--space-sm) var(--space-md)}}.diff-icon{font-size:2rem;width:50px;text-align:center}@media (min-width: 480px){.diff-icon{font-size:1.5rem;width:40px}}.diff-name{font-size:1.1rem;font-weight:600;color:var(--text-primary);display:block}@media (min-width: 480px){.diff-name{font-size:1rem}}.diff-desc{font-size:.85rem;color:var(--text-secondary);display:block;margin-top:2px}@media (min-width: 480px){.diff-desc{font-size:.75rem}}.login-screen{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--space-xl);padding-top:80px;gap:var(--space-lg)}@media (min-width: 600px){.login-screen{padding-top:70px}}.login-container{width:100%;max-width:400px;background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-xl);box-shadow:var(--shadow-lg)}.login-header{text-align:center;margin-bottom:var(--space-xl)}.login-header h1{font-size:1.5rem;margin-bottom:var(--space-sm);color:var(--accent)}.login-header p{color:var(--text-secondary);font-size:.9rem}.free-account-badge{display:inline-block;background:#27ae6033;color:#2ecc71;padding:var(--space-xs) var(--space-md);border-radius:var(--radius-lg);font-size:.85rem;font-weight:600;margin-top:var(--space-sm);border:1px solid rgba(39,174,96,.3)}.forgot-password-link{display:block;text-align:right;font-size:.85rem;color:var(--text-secondary);text-decoration:none;margin-top:var(--space-xs);transition:var(--transition-fast)}.forgot-password-link:hover{color:var(--accent)}.success-box{text-align:center;padding:var(--space-xl);background:#27ae601a;border:1px solid rgba(39,174,96,.3);border-radius:var(--radius-lg)}.success-box .success-icon{width:60px;height:60px;margin:0 auto var(--space-md);background:#27ae6033;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.5rem;color:#2ecc71}.success-box h3{color:#2ecc71;margin-bottom:var(--space-sm)}.success-box p{color:var(--text-secondary);font-size:.9rem;margin-bottom:var(--space-sm)}.success-box .success-note{font-size:.8rem;color:var(--text-muted)}.login-tabs{display:flex;gap:var(--space-sm);margin-bottom:var(--space-lg)}.login-tab{flex:1;padding:var(--space-sm) var(--space-md);border:none;background:transparent;color:var(--text-secondary);font-size:1rem;cursor:pointer;border-bottom:2px solid transparent;transition:var(--transition-fast)}.login-tab:hover{color:var(--text-primary)}.login-tab.active{color:var(--accent);border-bottom-color:var(--accent)}.login-form{display:flex;flex-direction:column;gap:var(--space-md)}.form-group{display:flex;flex-direction:column;gap:var(--space-xs)}.form-group label{font-size:.9rem;color:var(--text-secondary)}.form-group input{padding:var(--space-sm) var(--space-md);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-sm);background:#0003;color:var(--text-primary);font-size:1rem;transition:var(--transition-fast)}.form-group input:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 2px #d4af3733}.form-group input::placeholder{color:var(--text-muted)}.form-error{background:#c0392b33;border:1px solid var(--danger);color:#ff6b6b;padding:var(--space-sm) var(--space-md);border-radius:var(--radius-sm);font-size:.9rem}.login-button{padding:var(--space-md);background:var(--accent);color:var(--bg-dark);border:none;border-radius:var(--radius-sm);font-size:1rem;font-weight:600;cursor:pointer;transition:var(--transition-fast);margin-top:var(--space-sm)}.login-button:hover:not(:disabled){background:var(--accent-light)}.login-button:disabled{opacity:.6;cursor:not-allowed}.login-divider{display:flex;align-items:center;margin:var(--space-lg) 0;color:var(--text-muted);font-size:.85rem}.login-divider:before,.login-divider:after{content:"";flex:1;height:1px;background:#ffffff1a}.login-divider span{padding:0 var(--space-md)}.guest-link{display:block;text-align:center;color:var(--text-secondary);text-decoration:none;padding:var(--space-sm);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-sm);transition:var(--transition-fast)}.guest-link:hover{color:var(--text-primary);border-color:#fff3}.login-note{text-align:center;font-size:.8rem;color:var(--text-muted);margin-top:var(--space-md)}.profile-screen{min-height:100vh;padding:var(--space-lg);padding-top:80px}.profile-container{max-width:800px;margin:0 auto}.profile-header{display:flex;align-items:center;gap:var(--space-xl);margin-bottom:var(--space-xl);padding:var(--space-xl);background:var(--bg-card);border-radius:var(--radius-lg)}@media (min-width: 600px){.profile-header{flex-direction:column;text-align:center}}.profile-avatar{width:80px;height:80px;border-radius:var(--radius-full);background:var(--accent);display:flex;align-items:center;justify-content:center;font-size:2.5rem;color:var(--bg-dark)}.profile-info h1{font-size:1.5rem;margin-bottom:var(--space-xs)}.profile-info .email{color:var(--text-muted);font-size:.9rem}.profile-stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:var(--space-md);margin-bottom:var(--space-xl)}@media (min-width: 600px){.profile-stats-grid{grid-template-columns:repeat(2,1fr)}}.profile-stat-card{background:var(--bg-card);border-radius:var(--radius-md);padding:var(--space-lg);text-align:center}.profile-stat-card .stat-icon{font-size:1.5rem;margin-bottom:var(--space-sm)}.profile-stat-card .stat-value{font-size:2rem;font-weight:700;color:var(--accent);line-height:1;margin-bottom:var(--space-xs)}.profile-stat-card .stat-label{font-size:.8rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.profile-section{background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-xl);margin-bottom:var(--space-lg)}.profile-section h2{font-size:1.25rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(255,255,255,.1)}.badges-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(120px,1fr));gap:var(--space-md)}.badge-item{display:flex;flex-direction:column;align-items:center;gap:var(--space-sm);padding:var(--space-md);background:#ffffff08;border-radius:var(--radius-md);opacity:.4;transition:var(--transition-fast)}.badge-item.earned{opacity:1;background:#d4af371a}.badge-icon{font-size:2rem}.badge-name{font-size:.75rem;color:var(--text-secondary);text-align:center}.rating-history{height:200px;display:flex;align-items:flex-end;gap:2px;padding:var(--space-md) 0}.rating-bar{flex:1;background:var(--accent);border-radius:2px 2px 0 0;min-height:4px;transition:var(--transition-fast)}.rating-bar:hover{background:var(--accent-light)}.profile-actions{display:flex;gap:var(--space-md);justify-content:center;margin-top:var(--space-xl)}.logout-btn{padding:var(--space-sm) var(--space-lg);background:#c0392b33;color:#e74c3c;border:1px solid rgba(192,57,43,.3);border-radius:var(--radius-sm);cursor:pointer;transition:var(--transition-fast)}.logout-btn:hover{background:#c0392b4d}.puzzles-hub-screen{min-height:100vh;padding-top:80px;padding-bottom:var(--space-xxl)}.puzzles-hub-container{max-width:900px;margin:0 auto;padding:0 var(--space-lg)}.puzzles-hub-container>*{margin-left:auto;margin-right:auto}.puzzles-hub-header{text-align:center;margin-bottom:var(--space-xxl)}.puzzles-hub-header h1{font-size:2.5rem;font-weight:700;margin-bottom:var(--space-md);background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}@media (min-width: 768px){.puzzles-hub-header h1{font-size:1.8rem}}.puzzles-hub-header p{color:var(--text-secondary);font-size:1.1rem;max-width:500px;margin:0 auto}.puzzle-modes-grid{display:grid;grid-template-columns:1fr;gap:var(--space-lg);margin-bottom:var(--space-xxl)}@media (min-width: 768px){.puzzle-modes-grid{grid-template-columns:repeat(2,1fr)}}.puzzle-mode-card{display:flex;align-items:flex-start;gap:var(--space-md);padding:var(--space-lg);background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);text-decoration:none;color:inherit;position:relative;overflow:hidden}.puzzle-mode-card:hover:hover{transform:translateY(-4px);border-color:#d4af374d;box-shadow:var(--shadow-lg)}.puzzle-mode-card:hover .puzzle-mode-arrow{opacity:1;right:var(--space-sm)}@media (min-width: 768px){.puzzle-mode-card{padding:var(--space-md)}}.puzzle-mode-icon{flex-shrink:0;width:48px;height:48px;display:flex;align-items:center;justify-content:center;background:#d4af3726;border-radius:var(--radius-md);font-size:1.5rem}@media (min-width: 768px){.puzzle-mode-icon{width:40px;height:40px;font-size:1.25rem}}.icon-target:before{content:"🎯︎"}.icon-calendar:before{content:"📅︎"}.icon-lightning:before{content:"⚡︎"}.icon-tag:before{content:"🏷︎"}.puzzle-mode-content{flex:1;min-width:0}.puzzle-mode-content h2{font-size:1.1rem;font-weight:600;margin-bottom:var(--space-xs);color:var(--text-primary)}.puzzle-mode-content p{font-size:.9rem;color:var(--text-secondary);line-height:1.4;margin-bottom:var(--space-sm)}.puzzle-mode-stat{display:flex;align-items:center;gap:var(--space-sm)}.puzzle-mode-stat .stat-label{font-size:.8rem;color:var(--text-muted)}.puzzle-mode-stat .stat-value{font-size:1rem;font-weight:600;color:var(--accent)}.puzzle-mode-arrow{position:absolute;right:var(--space-md);top:50%;transform:translateY(-50%);opacity:0;transition:all var(--transition-fast)}.puzzle-mode-arrow:before{content:"→";font-size:1.25rem;color:var(--accent)}.puzzles-hub-stats{background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-xl);margin-bottom:var(--space-xl)}.puzzles-hub-stats h3{font-size:1.1rem;margin-bottom:var(--space-lg);color:var(--text-secondary)}.stats-row{display:flex;justify-content:space-around;gap:var(--space-lg)}@media (min-width: 768px){.stats-row{flex-direction:column;gap:var(--space-md)}}.stat-box{text-align:center}.stat-box .stat-number{display:block;font-size:2rem;font-weight:700;color:var(--accent)}.stat-box .stat-label{font-size:.85rem;color:var(--text-muted)}.auth-prompt-box{text-align:center;padding:var(--space-xl);background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);margin-top:var(--space-xl)}.auth-prompt-box p{color:var(--text-secondary);margin-bottom:var(--space-md)}.auth-prompt-buttons{display:flex;justify-content:center;gap:var(--space-md);flex-wrap:wrap}.puzzles-hub-ad{margin:var(--space-xl) auto;text-align:center}.puzzle-page-header{text-align:center;margin-bottom:var(--space-lg)}.puzzle-page-header h1{font-size:2rem;color:var(--accent);margin-bottom:var(--space-xs)}@media (min-width: 600px){.puzzle-page-header h1{font-size:1.75rem}}.puzzle-page-header .page-subtitle{color:var(--text-secondary);font-size:1rem}.puzzle-board-section{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);width:100%;max-width:min(95vw,400px);margin:0 auto}@media (min-width: 600px){.puzzle-board-section{max-width:min(85vw,480px)}}.puzzle-container{max-width:520px}.puzzle-header{width:100%;margin-bottom:var(--space-md);display:flex;align-items:center;justify-content:space-between;padding:var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);flex-wrap:wrap;gap:var(--space-md)}.puzzle-info{display:flex;align-items:center;justify-content:center;gap:var(--space-lg);background:var(--bg-card);padding:var(--space-md) var(--space-lg);border-radius:var(--radius-md);flex-wrap:wrap;color:var(--text-secondary);font-size:.85rem}@media (min-width: 480px){.puzzle-info{gap:var(--space-md);padding:var(--space-sm) var(--space-md)}}.puzzle-info-item{display:flex;align-items:center;gap:var(--space-xs)}.puzzle-mate-in{font-size:1.25rem;font-weight:700;color:var(--accent)}@media (min-width: 480px){.puzzle-mate-in{font-size:1rem}}.puzzle-difficulty-badge{background:#d4af3733;color:var(--accent);padding:var(--space-xs) var(--space-md);border-radius:var(--radius-lg);font-size:.85rem;font-weight:600}.puzzle-stats-bar{display:flex;gap:var(--space-xl);flex-wrap:wrap;justify-content:center;margin:0 auto var(--space-lg);max-width:min(95vw,400px)}@media (min-width: 600px){.puzzle-stats-bar{gap:var(--space-lg);max-width:min(85vw,480px)}}.stat-item{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs)}.stat-label{font-size:.75rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.stat-value{font-size:1.5rem;font-weight:700;color:var(--accent)}@media (min-width: 600px){.stat-value{font-size:1.25rem}}.puzzle-board-container{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);position:relative;transition:var(--transition-fast)}.puzzle-board-container.feedback-correct{box-shadow:0 0 20px #27ae6099}.puzzle-board-container.feedback-incorrect{animation:shake .3s ease-in-out;box-shadow:0 0 20px #c0392b99}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}.puzzle-board-wrapper{position:relative;display:flex;flex-direction:column;align-items:center;margin-bottom:var(--space-md)}.puzzle-status{width:100%;text-align:center;padding:var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);margin:var(--space-md) 0;transition:all var(--transition-fast)}.puzzle-status.correct{background:#27ae6033;border:1px solid var(--success)}.puzzle-status.wrong{background:#c0392b33;border:1px solid var(--danger)}.puzzle-status.success{background:#27ae6033;color:var(--success)}.puzzle-status.error{background:#c0392b33;color:var(--danger)}.puzzle-status.loading{color:var(--text-muted)}#puzzle-status-text{font-weight:600;font-size:1rem}.puzzle-status.correct #puzzle-status-text{color:var(--success)}.puzzle-status.wrong #puzzle-status-text{color:var(--danger)}.puzzle-feedback{padding:var(--space-md) var(--space-xl);border-radius:var(--radius-md);font-size:1.1rem;font-weight:600;text-align:center;min-width:200px}.puzzle-feedback.info{background:#d4af3733;color:var(--accent-light);border:1px solid var(--accent)}.puzzle-feedback.correct{background:#27ae6033;color:#2ecc71;border:1px solid var(--success)}.puzzle-feedback.incorrect{background:#c0392b33;color:#e74c3c;border:1px solid var(--danger)}.puzzle-feedback.complete{background:#d4af374d;color:var(--accent-light);border:2px solid var(--accent)}@media (min-width: 600px){.puzzle-feedback{padding:var(--space-sm) var(--space-md);font-size:1rem}}.puzzle-message{padding:var(--space-md) var(--space-xl);border-radius:var(--radius-md);font-size:1.1rem;font-weight:600;text-align:center;width:100%;max-width:min(95vw,400px);margin:0 auto;background:#d4af3733;color:var(--accent-light);border:1px solid var(--accent)}@media (min-width: 600px){.puzzle-message{max-width:min(85vw,480px)}}.puzzle-message.correct{background:#27ae6033;color:#2ecc71;border-color:var(--success)}.puzzle-message.incorrect{background:#c0392b33;color:#e74c3c;border-color:var(--danger)}.puzzle-message.solved{background:#27ae604d;color:#2ecc71;border:2px solid var(--success)}.puzzle-controls{display:flex;gap:var(--space-md);width:100%;max-width:min(95vw,400px);margin:var(--space-md) auto 0;flex-wrap:wrap;justify-content:center}@media (min-width: 600px){.puzzle-controls{max-width:min(85vw,480px)}}.puzzle-controls .btn,.puzzle-controls .puzzle-btn{flex:1;padding:var(--space-sm) var(--space-md);min-width:120px}.puzzle-controls .btn-icon{font-size:1rem;margin-right:var(--space-xs)}.puzzle-actions{display:flex;justify-content:center;gap:var(--space-md);margin-bottom:var(--space-md)}.rating-change{font-size:1rem;font-weight:600;animation:rating-pop .5s ease-out}.rating-change.positive{color:var(--success)}.rating-change.negative{color:var(--danger)}@keyframes rating-pop{0%{transform:scale(1.5);opacity:0}50%{transform:scale(1.2)}to{transform:scale(1);opacity:1}}.puzzle-loading{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);padding:var(--space-xxl)}.puzzle-loading-spinner{width:48px;height:48px;border:4px solid rgba(212,175,55,.2);border-top-color:var(--accent);border-radius:50%;animation:spin 1s linear infinite}.puzzle-themes{display:flex;flex-wrap:wrap;gap:var(--space-sm);justify-content:center;width:100%;max-width:min(95vw,400px);margin:0 auto var(--space-md)}@media (min-width: 600px){.puzzle-themes{max-width:min(85vw,480px)}}.puzzle-themes:empty{display:none}.puzzle-theme-tag{background:#d4af3733;color:var(--accent);padding:2px 8px;border-radius:var(--radius-sm);font-size:.75rem}.puzzle-status-overlay{position:absolute;top:0;right:0;bottom:0;left:0;background:#0f0f14f2;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-lg);z-index:10;border-radius:var(--radius-md);-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);padding:var(--space-xl)}.status-message{font-size:1.75rem;font-weight:700;text-align:center;padding:var(--space-sm) var(--space-lg);border-radius:var(--radius-md)}.status-message.success{color:#2ecc71;text-shadow:0 0 20px rgba(46,204,113,.4)}.status-message.failure{color:#e67e22;text-shadow:0 0 20px rgba(230,126,34,.4)}@media (min-width: 480px){.status-message{font-size:1.35rem}}.status-details{color:var(--text-secondary);text-align:center;width:100%}.result-stats-grid{display:flex;justify-content:center;gap:var(--space-xl);flex-wrap:wrap}@media (min-width: 480px){.result-stats-grid{gap:var(--space-lg)}}.result-stat{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs);min-width:70px}.result-label{font-size:.75rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.result-value{font-size:1.5rem;font-weight:700;color:var(--text-primary);font-variant-numeric:tabular-nums}.result-value.positive{color:#2ecc71}.result-value.negative{color:#e74c3c}@media (min-width: 480px){.result-value{font-size:1.25rem}}.puzzle-links{display:flex;gap:var(--space-md);flex-wrap:wrap;justify-content:center;margin-top:var(--space-lg)}.puzzle-link-card{background:var(--bg-card);padding:var(--space-md) var(--space-lg);border-radius:var(--radius-md);text-decoration:none;color:var(--text-primary);transition:var(--transition-fast);border:1px solid transparent}.puzzle-link-card:hover{border-color:var(--accent);transform:translateY(-2px)}.puzzle-hint-overlay{position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none;z-index:5}.hint-arrow{filter:drop-shadow(0 2px 4px rgba(0,0,0,.3))}#puzzle-screen.active{display:flex!important;flex-direction:column;justify-content:center;align-items:center;padding:var(--space-md)}.elo-slider-container{background:var(--bg-card);border-radius:var(--radius-md);padding:var(--space-xl);margin-bottom:var(--space-xl);border:1px solid rgba(255,255,255,.1)}@media (min-width: 480px){.elo-slider-container{padding:var(--space-lg)}}.elo-display{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);margin-bottom:var(--space-lg)}.elo-label{color:var(--text-secondary);font-size:.9rem}.elo-value{font-size:2rem;font-weight:700;color:var(--accent);min-width:80px;text-align:center;font-variant-numeric:tabular-nums}@media (min-width: 480px){.elo-value{font-size:1.5rem}}.elo-slider{width:100%;height:8px;border-radius:var(--radius-sm);background:linear-gradient(to right,#22c55e,#3b82f6,#d4af37,#f97316,#ef4444);outline:none;-webkit-appearance:none;-moz-appearance:none;appearance:none;cursor:pointer}.elo-slider::-webkit-slider-thumb{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:24px;height:24px;border-radius:var(--radius-full);background:var(--text-primary);cursor:pointer;box-shadow:var(--shadow-md);border:3px solid var(--accent);transition:transform var(--transition-fast)}.elo-slider::-webkit-slider-thumb:hover{transform:scale(1.1)}.elo-slider::-moz-range-thumb{width:24px;height:24px;border-radius:var(--radius-full);background:var(--text-primary);cursor:pointer;box-shadow:var(--shadow-md);border:3px solid var(--accent)}.elo-range-labels{display:flex;justify-content:space-between;margin-top:var(--space-sm);color:var(--text-muted);font-size:.8rem}.puzzle-info-preview{margin-bottom:var(--space-xl)}.puzzle-preview-badge{display:inline-flex;align-items:center;gap:var(--space-sm);background:var(--bg-card);padding:var(--space-sm) var(--space-lg);border-radius:var(--radius-lg);border:1px solid rgba(212,175,55,.3)}.badge-icon{font-size:1.25rem}.badge-text{color:var(--text-secondary);font-size:.9rem}.puzzle-timer{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);font-size:1.5rem;font-weight:700;font-family:monospace;color:var(--accent);margin:var(--space-sm) auto}.daily-puzzle-screen{min-height:100vh;display:flex;flex-direction:column;padding-top:60px;overflow-x:hidden}.daily-puzzle-container{flex:1;display:flex;flex-direction:column;padding:var(--space-lg);max-width:1200px;margin:0 auto;width:100%;box-sizing:border-box}.daily-header{text-align:center;margin-bottom:var(--space-xl)}.daily-header h1{font-size:2rem;color:var(--accent);margin-bottom:var(--space-xs)}.daily-date{color:var(--text-secondary);font-size:1rem;text-transform:capitalize}.daily-content{display:grid;grid-template-columns:1fr;gap:var(--space-xl);align-items:start}@media (min-width: 900px){.daily-content{grid-template-columns:1fr 300px}}.daily-board-section{display:flex;flex-direction:column;align-items:center;gap:var(--space-md);width:100%;max-width:min(87vw,400px);margin:0 auto}@media (min-width: 600px){.daily-board-section{max-width:min(85vw,480px)}}@media (min-width: 900px){.daily-board-section{max-width:none;margin:0}}.daily-leaderboard-section{background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-lg);order:2}.daily-leaderboard-section h2{font-size:1.25rem;color:var(--accent);margin-bottom:var(--space-xs)}@media (min-width: 900px){.daily-leaderboard-section{order:unset}}.leaderboard-subtitle{color:var(--text-muted);font-size:.85rem;margin-bottom:var(--space-lg)}.leaderboard-list{display:flex;flex-direction:column;gap:var(--space-sm)}.leaderboard-entry{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-sm) var(--space-md);background:#ffffff08;border-radius:var(--radius-sm);transition:var(--transition-fast)}.leaderboard-entry:hover{background:#ffffff0f}.leaderboard-entry.current-user{background:#d4af371a;border:1px solid rgba(212,175,55,.3)}.leaderboard-rank{font-size:1.1rem;min-width:32px}.leaderboard-name{flex:1;color:var(--text-primary);font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.leaderboard-time{color:var(--accent);font-weight:600;font-family:monospace}.leaderboard-empty{text-align:center;padding:var(--space-xl);color:var(--text-muted)}.leaderboard-divider{text-align:center;color:var(--text-muted);padding:var(--space-xs)}.leaderboard-loading{display:flex;justify-content:center;padding:var(--space-xl)}.board-loading{grid-column:1/-1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-md);padding:var(--space-xxl);color:var(--text-muted)}.daily-footer{margin-top:var(--space-xl);text-align:center}.back-link{color:var(--text-secondary);text-decoration:none;transition:var(--transition-fast)}.back-link:hover{color:var(--accent)}.puzzle-timer{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);font-size:1.5rem;font-weight:700;font-family:monospace;color:var(--accent);margin-bottom:var(--space-sm)}.puzzle-timer .timer-icon{font-size:1.25rem}.puzzle-timer .timer-value{min-width:60px}.rush-header{text-align:center;margin-bottom:var(--space-xl)}.rush-header h1{font-size:2.5rem;color:var(--accent);margin-bottom:var(--space-xs)}.rush-subtitle{color:var(--text-secondary);font-size:1.1rem}.rush-setup{max-width:500px;margin:0 auto;text-align:center;padding:var(--space-xl);background:var(--bg-card);border-radius:var(--radius-lg)}.rush-setup h2{font-size:1.5rem;margin-bottom:var(--space-lg)}.duration-options{display:flex;gap:var(--space-md);justify-content:center;margin-bottom:var(--space-xl);flex-wrap:wrap}@media (min-width: 600px){.duration-options{flex-direction:column}}.duration-btn{padding:var(--space-md) var(--space-xl);font-size:1.1rem;font-weight:600;background:#ffffff0d;border:2px solid rgba(255,255,255,.1);border-radius:var(--radius-md);color:var(--text-primary);cursor:pointer;transition:var(--transition-fast)}.duration-btn:hover{background:#d4af371a;border-color:#d4af374d}.duration-btn.selected{background:var(--accent);border-color:var(--accent);color:var(--bg-dark)}@media (min-width: 600px){.duration-btn{width:100%}}.start-rush-btn{padding:var(--space-md) var(--space-xxl);font-size:1.25rem;font-weight:700;background:var(--accent);border:none;border-radius:var(--radius-md);color:var(--bg-dark);cursor:pointer;transition:var(--transition-fast)}.start-rush-btn:hover{background:var(--accent-light);transform:scale(1.02)}.rush-game{max-width:600px;margin:0 auto;width:100%}.rush-stats{display:flex;justify-content:space-between;align-items:center;margin-bottom:var(--space-lg);padding:var(--space-md) var(--space-lg);background:var(--bg-card);border-radius:var(--radius-md)}@media (min-width: 600px){.rush-stats{flex-direction:column;gap:var(--space-md)}}.rush-timer{display:flex;align-items:center;gap:var(--space-sm);font-size:1.5rem;font-weight:700;font-family:monospace}.rush-timer .timer-icon{font-size:1.25rem}.rush-timer .timer-value{min-width:60px}.rush-timer.low-time{color:var(--danger);animation:pulse .5s infinite}.rush-score{display:flex;flex-direction:column;align-items:center}.rush-score .score-label{font-size:.75rem;color:var(--text-muted);text-transform:uppercase}.rush-score .score-value{font-size:2rem;font-weight:700;color:var(--accent)}.rush-mistakes{display:flex;flex-direction:column;align-items:center}.rush-mistakes .mistakes-label{font-size:.75rem;color:var(--text-muted);text-transform:uppercase;margin-bottom:var(--space-xs)}.rush-mistakes .mistakes-value{display:flex;gap:var(--space-xs)}.rush-mistakes .heart{font-size:1.25rem;color:var(--danger);transition:var(--transition-fast)}.rush-mistakes .heart.lost{color:var(--text-muted);opacity:.3}.rush-board-container{margin-bottom:var(--space-md)}.rush-controls{display:flex;justify-content:center;margin-bottom:var(--space-md)}.skip-btn{padding:var(--space-sm) var(--space-lg);font-size:1rem;font-weight:600;background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-sm);color:var(--text-secondary);cursor:pointer;transition:var(--transition-fast)}.skip-btn:hover{background:#ffffff1a;color:var(--text-primary)}.rush-feedback{text-align:center;padding:var(--space-md);border-radius:var(--radius-sm);font-weight:600;display:none}.rush-feedback.success{background:#27ae6033;color:var(--success);display:block}.rush-feedback.error{background:#c0392b33;color:var(--danger);display:block}.rush-feedback.warning{background:#f39c1233;color:var(--warning);display:block}.rush-feedback.info{background:#d4af3733;color:var(--accent);display:block}.rush-result{max-width:500px;margin:0 auto;text-align:center;padding:var(--space-xl);background:var(--bg-card);border-radius:var(--radius-lg)}.rush-result h2{font-size:1.75rem;color:var(--accent);margin-bottom:var(--space-xl)}.result-score{margin-bottom:var(--space-xl)}.result-score .result-label{display:block;font-size:1rem;color:var(--text-muted);margin-bottom:var(--space-sm)}.result-score .result-value{font-size:4rem;font-weight:700;color:var(--accent)}.result-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--space-md);margin-bottom:var(--space-xl)}@media (min-width: 600px){.result-stats{grid-template-columns:1fr}}.result-stat{padding:var(--space-md);background:#ffffff08;border-radius:var(--radius-sm)}.result-stat .stat-label{display:block;font-size:.75rem;color:var(--text-muted);text-transform:uppercase;margin-bottom:var(--space-xs)}.result-stat .stat-value{font-size:1.5rem;font-weight:600}.highscore-notice{margin-bottom:var(--space-lg);color:var(--success);font-weight:600}.highscore-notice.is-highscore{font-size:1.25rem;animation:pulse 1s 3}.rush-result .puzzle-btn{display:block;width:auto;margin:0 auto var(--space-md);padding:var(--space-md) var(--space-xl)}.play-again-btn{padding:var(--space-md) var(--space-xl);font-size:1.1rem;font-weight:600;background:var(--accent);border:none;border-radius:var(--radius-md);color:var(--bg-dark);cursor:pointer;transition:var(--transition-fast);margin-bottom:var(--space-md);display:block;width:100%}.play-again-btn:hover{background:var(--accent-light)}.themed-puzzles-screen{min-height:100vh;display:flex;flex-direction:column;padding:var(--space-lg);padding-top:80px}.themed-header{text-align:center;margin-bottom:var(--space-xl)}.themed-header h1{font-size:2rem;color:var(--accent);margin-bottom:var(--space-xs)}.themed-subtitle{color:var(--text-secondary);font-size:1.1rem}.themed-container{flex:1;max-width:1200px;margin:0 auto;width:100%}.theme-selection{display:flex;flex-direction:column;gap:var(--space-xl)}.theme-category{background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-lg)}.category-title{font-size:1.25rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(212,175,55,.2)}.theme-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:var(--space-md)}@media (min-width: 600px){.theme-grid{grid-template-columns:repeat(2,1fr)}}.theme-card{display:flex;flex-direction:column;align-items:center;gap:var(--space-sm);padding:var(--space-lg) var(--space-md);background:#ffffff08;border:1px solid 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.puzzle-controls{display:flex;justify-content:center;gap:16px}.back-to-themes-btn{padding:var(--space-sm) var(--space-md);background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-sm);color:var(--text-secondary);cursor:pointer;transition:var(--transition-fast);font-size:.9rem}.back-to-themes-btn:hover{background:#ffffff1a;color:var(--text-primary)}@media (min-width: 600px){.back-to-themes-btn{width:100%}}.current-theme-info{display:flex;align-items:center;gap:var(--space-sm);font-weight:600}.current-theme-icon{font-size:1.5rem}.current-theme-name{color:var(--accent)}.puzzle-rating{font-family:monospace;color:var(--text-muted);font-size:.9rem}.themed-footer{margin-top:var(--space-lg);text-align:center}.themed-puzzle-area .puzzle-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:var(--space-lg);padding:var(--space-md);background:var(--bg-card);border-radius:var(--radius-md);flex-wrap:wrap;gap:var(--space-md)}@media (min-width: 600px){.themed-puzzle-area .puzzle-header{flex-direction:column;text-align:center}}.puzzle-board-wrapper{margin-bottom:var(--space-md)}.hint-btn,.next-btn{padding:var(--space-sm) var(--space-lg);font-size:1rem;font-weight:600;border-radius:var(--radius-sm);cursor:pointer;transition:var(--transition-fast)}.hint-btn{background:#ffffff0d;border:1px solid rgba(255,255,255,.1);color:var(--text-secondary)}.hint-btn:hover{background:#ffffff1a;color:var(--text-primary)}.next-btn{background:var(--accent);border:none;color:var(--bg-dark)}.next-btn:hover{background:var(--accent-light)}.themed-puzzle-area .puzzle-themes{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}.puzzle-theme-tag{padding:var(--space-xs) var(--space-sm);background:#d4af371a;border-radius:var(--radius-sm);font-size:.75rem;color:var(--accent)}.themed-puzzle-area .puzzle-timer{display:flex;align-items:center;justify-content:center;gap:8px;font-size:1.25rem;font-weight:700;font-family:monospace;color:var(--accent)}.retry-btn{background:#e67e2233;border:1px solid rgba(230,126,34,.5);color:#e67e22}.retry-btn:hover{background:#e67e224d;border-color:#e67e22}.openings-list-page{max-width:1200px;margin:0 auto;padding:var(--space-lg);padding-top:80px;text-align:left}.openings-list-page .page-header{text-align:center;margin-bottom:var(--space-xl)}.openings-list-page .page-title{font-size:2.25rem;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:var(--space-sm)}@media (min-width: 600px){.openings-list-page .page-title{font-size:1.75rem}}.openings-list-page .page-subtitle{color:var(--text-secondary);font-size:1.1rem}@media (min-width: 600px){.openings-list-page{padding:var(--space-md);padding-top:70px}}.breadcrumb{display:flex;gap:var(--space-sm);align-items:center;margin-bottom:var(--space-lg);font-size:.875rem;color:var(--text-muted)}.breadcrumb a{color:var(--accent);text-decoration:none;transition:var(--transition-fast)}.breadcrumb a:hover{text-decoration:underline}.opening-category{margin-bottom:var(--space-xxl)}.opening-category .category-title{font-size:1.5rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(212,175,55,.2)}.openings-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:var(--space-md)}.opening-card{display:block;padding:var(--space-lg);background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);text-decoration:none;color:var(--text-primary);position:relative}.opening-card-title{font-size:1.1rem;font-weight:600;margin-bottom:var(--space-xs)}.opening-card-subtitle{font-size:.85rem;color:var(--text-muted);font-style:italic;margin-bottom:var(--space-sm)}.opening-card-eco{display:inline-block;background:var(--accent);color:var(--bg-dark);padding:2px 8px;border-radius:var(--radius-sm);font-size:.75rem;font-weight:600}.opening-detail-page{max-width:900px;margin:0 auto;padding:var(--space-lg);padding-top:80px;text-align:left}.opening-detail-page .page-header{text-align:center;margin-bottom:var(--space-xl)}.opening-detail-page .page-title{font-size:2.25rem;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:var(--space-sm)}@media (min-width: 600px){.opening-detail-page .page-title{font-size:1.75rem}}.opening-detail-page .page-subtitle{color:var(--text-muted);font-size:1rem;font-style:italic;margin-bottom:var(--space-md)}@media (min-width: 600px){.opening-detail-page{padding:var(--space-md);padding-top:70px}}.eco-badge{display:inline-block;background:var(--accent);color:var(--bg-dark);padding:4px 12px;border-radius:var(--radius-sm);font-size:.875rem;font-weight:600}.opening-detail-page .section-title{font-size:1.25rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(212,175,55,.2)}.two-column-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-lg)}@media (min-width: 768px){.two-column-grid{grid-template-columns:1fr}}.opening-animation-wrapper{display:flex;flex-direction:column;align-items:center;gap:var(--space-md)}.move-explanation{text-align:center;padding:var(--space-md);background:#d4af371a;border-radius:var(--radius-md);max-width:400px}.move-explanation .move-san{font-size:1.25rem;font-weight:600;color:var(--accent);margin-bottom:var(--space-xs)}.move-explanation .move-text{color:var(--text-secondary);font-size:.9rem}.moves-list{display:flex;flex-direction:column;gap:var(--space-sm)}.move-item{display:flex;align-items:baseline;gap:var(--space-sm);padding:var(--space-sm) 0;border-bottom:1px solid rgba(255,255,255,.05)}.move-number{font-weight:600;color:var(--accent);min-width:30px}.move-notation{font-family:monospace;font-weight:600;color:var(--text-primary);min-width:60px}.move-explanation-text{color:var(--text-secondary);font-size:.9rem}.pros-cons-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-lg)}@media (min-width: 768px){.pros-cons-grid{grid-template-columns:1fr}}.pros h3,.cons h3{font-size:1.1rem;margin-bottom:var(--space-md)}.pros ul,.cons ul{list-style:none;margin:0;padding:0}.pros li,.cons li{padding:var(--space-sm) 0;color:var(--text-secondary);border-bottom:1px solid rgba(255,255,255,.05)}.pros h3{color:var(--success)}.pros li:before{content:"✓ ";color:var(--success)}.cons h3{color:var(--danger)}.cons li:before{content:"✗ ";color:var(--danger)}.famous-games{display:flex;flex-direction:column;gap:var(--space-sm)}.famous-game{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-md);background:#ffffff08;border-radius:var(--radius-sm)}.famous-game .players{flex:1;font-weight:500}.famous-game .year{color:var(--text-muted);font-size:.9rem}.famous-game .result{font-weight:600;color:var(--accent)}@media (min-width: 600px){.famous-game{flex-direction:column;align-items:flex-start;gap:var(--space-xs)}}.related-openings-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:var(--space-md)}@media (min-width: 600px){.related-openings-grid{grid-template-columns:1fr}}.opening-not-found{min-height:60vh;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding-top:80px}.opening-not-found h1{font-size:2rem;color:var(--accent);margin-bottom:var(--space-md)}.opening-not-found p{color:var(--text-secondary);margin-bottom:var(--space-xl)}.opening-category-screen{min-height:100vh;padding-top:80px;padding-bottom:var(--space-xxl)}.opening-category-container{max-width:900px;margin:0 auto;padding:0 var(--space-lg)}.opening-category-header{text-align:center;margin-bottom:var(--space-xxl)}.opening-category-header h1{font-size:2.5rem;font-weight:700;margin-bottom:var(--space-md);background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}@media (min-width: 768px){.opening-category-header h1{font-size:1.8rem}}.opening-category-header p{color:var(--text-secondary);font-size:1.1rem;max-width:600px;margin:0 auto;line-height:1.5}.openings-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-md);margin-bottom:var(--space-xxl)}@media (min-width: 600px){.openings-grid{grid-template-columns:1fr}}.opening-card{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-lg);background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);text-decoration:none;color:inherit;position:relative;overflow:hidden}.opening-card:hover:hover{transform:translateY(-4px);border-color:#d4af374d;box-shadow:var(--shadow-lg)}.opening-card:hover .opening-card-arrow{opacity:1;right:var(--space-sm)}@media (min-width: 768px){.opening-card{padding:var(--space-md)}}.opening-card-content{flex:1;min-width:0}.opening-card-content h2{font-size:1rem;font-weight:600;margin-bottom:var(--space-xs);color:var(--text-primary)}.opening-card-content .opening-eco{font-size:.75rem;color:var(--accent);font-weight:500;margin-bottom:var(--space-xs)}.opening-card-content .opening-pgn{font-size:.85rem;color:var(--text-muted);font-family:var(--font-mono, monospace)}.opening-card-arrow{position:absolute;right:var(--space-md);top:50%;transform:translateY(-50%);opacity:0;transition:all var(--transition-fast)}.opening-card-arrow:before{content:"→";font-size:1.25rem;color:var(--accent)}.other-categories{margin-top:var(--space-xxl);padding-top:var(--space-xl);border-top:1px solid var(--border-color)}.other-categories h2{font-size:1.25rem;font-weight:600;margin-bottom:var(--space-lg);color:var(--text-secondary);text-align:center}.categories-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-md)}@media (min-width: 768px){.categories-grid{grid-template-columns:repeat(2,1fr)}}@media (min-width: 600px){.categories-grid{grid-template-columns:1fr}}.category-card{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-lg);text-align:center;text-decoration:none;color:inherit}.category-card:hover:hover{transform:translateY(-4px);border-color:#d4af374d;box-shadow:var(--shadow-lg)}.category-card h3{font-size:1rem;font-weight:600;margin-bottom:var(--space-xs);color:var(--text-primary)}.category-card p{font-size:.85rem;color:var(--text-muted)}.category-card.category-card-all{background:#d4af371a;border-color:var(--accent)}.category-card.category-card-all h3{color:var(--accent)}.rules-page,.how-to-play-page,.legal-page{max-width:900px;margin:0 auto;padding:var(--space-lg);padding-top:80px;text-align:left}.rules-page .page-header,.how-to-play-page .page-header,.legal-page .page-header{text-align:center;margin-bottom:var(--space-xxl);padding-top:var(--space-lg)}.rules-page .page-header .logo,.how-to-play-page .page-header .logo,.legal-page .page-header .logo{font-size:3rem;margin-bottom:var(--space-md)}.rules-page .page-header h1,.how-to-play-page .page-header h1,.legal-page .page-header h1{font-size:2.25rem;background:linear-gradient(135deg,var(--text-primary) 0%,var(--accent) 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:var(--space-sm)}@media (min-width: 600px){.rules-page .page-header h1,.how-to-play-page .page-header h1,.legal-page .page-header h1{font-size:1.75rem}}.rules-page .page-subtitle,.how-to-play-page .page-subtitle,.legal-page .page-subtitle{color:var(--text-secondary);font-size:1.1rem}@media (min-width: 600px){.rules-page,.how-to-play-page,.legal-page{padding:var(--space-md);padding-top:70px}}.content-section{background:var(--bg-card);border-radius:var(--radius-md);border:1px solid rgba(255,255,255,.05);transition:all var(--transition-fast);padding:var(--space-xl);margin-bottom:var(--space-lg)}.content-section h2{font-size:1.5rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(212,175,55,.2)}.content-section h3{font-size:1.2rem;color:var(--text-primary);margin:var(--space-lg) 0 var(--space-md);display:flex;align-items:center;gap:var(--space-sm)}.content-section p{color:var(--text-secondary);margin-bottom:var(--space-md);line-height:1.7}.content-section ul,.content-section ol{color:var(--text-secondary);margin-left:var(--space-lg);margin-bottom:var(--space-md)}.content-section li{margin-bottom:var(--space-sm)}@media (min-width: 600px){.content-section{padding:var(--space-lg)}}.content-section a{color:#7eb8da;text-decoration:none}.content-section a:hover{text-decoration:underline}.highlight-box{background:#d4af371a;border-left:4px solid var(--accent);padding:var(--space-lg);margin:var(--space-lg) 0;border-radius:0 var(--radius-md) var(--radius-md) 0}.highlight-box strong{color:var(--accent)}.piece-icon{font-size:1.5rem;color:var(--accent)}.cta-section{text-align:center;margin:var(--space-xxl) 0}.cta-button{display:inline-block;padding:var(--space-md) var(--space-xxl);background:var(--accent);color:var(--bg-dark);border-radius:var(--radius-md);text-decoration:none;font-weight:600;font-size:1.1rem;transition:var(--transition-fast)}.cta-button:hover{background:var(--accent-light);transform:scale(1.02)}.not-found-screen{min-height:100vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:var(--space-xl)}.not-found-content{max-width:400px}.not-found-content h1{font-size:2rem;margin-bottom:var(--space-md)}.not-found-content p{color:var(--text-secondary);margin-bottom:var(--space-xl)}.not-found-icon{font-size:6rem;margin-bottom:var(--space-lg);opacity:.5}.admin-screen{min-height:100vh;padding:var(--space-lg);padding-top:80px}.admin-container{max-width:1000px;margin:0 auto}.admin-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:var(--space-xl);padding-bottom:var(--space-lg);border-bottom:1px solid rgba(255,255,255,.1)}.admin-header h1{font-size:1.75rem;color:var(--accent)}@media (min-width: 600px){.admin-header{flex-direction:column;gap:var(--space-md)}}.range-selector select{padding:var(--space-sm) var(--space-md);background:var(--bg-card);color:var(--text-primary);border:1px solid rgba(255,255,255,.2);border-radius:var(--radius-sm);font-size:.9rem;cursor:pointer}.range-selector select:focus{outline:none;border-color:var(--accent)}.admin-section{background:var(--bg-card);border-radius:var(--radius-lg);padding:var(--space-xl);margin-bottom:var(--space-lg)}.admin-section h2{font-size:1.25rem;color:var(--accent);margin-bottom:var(--space-lg);padding-bottom:var(--space-sm);border-bottom:1px solid rgba(255,255,255,.1)}.admin-section h3{font-size:1rem;color:var(--text-secondary);margin-top:var(--space-lg);margin-bottom:var(--space-md)}.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:var(--space-md);margin-bottom:var(--space-lg)}@media (min-width: 600px){.stats-grid{grid-template-columns:repeat(2,1fr)}}.stat-card{background:#ffffff08;border-radius:var(--radius-md);padding:var(--space-lg);text-align:center}.stat-card.highlight{background:#d4af371a;border:1px solid rgba(212,175,55,.2)}.stat-card .stat-value{font-size:2.5rem;font-weight:700;color:var(--accent);line-height:1;margin-bottom:var(--space-sm)}.stat-card .stat-label{font-size:.85rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.breakdown-list{display:flex;flex-direction:column;gap:var(--space-sm)}.breakdown-item{display:flex;justify-content:space-between;align-items:center;padding:var(--space-sm) var(--space-md);background:#ffffff08;border-radius:var(--radius-sm)}.breakdown-item .breakdown-label{color:var(--text-secondary)}.breakdown-item .breakdown-value{font-weight:600;color:var(--accent)}.admin-table-container{overflow-x:auto;margin-top:var(--space-md)}.admin-table{width:100%;border-collapse:collapse;font-size:.9rem}.admin-table th,.admin-table td{padding:var(--space-sm) var(--space-md);text-align:left;border-bottom:1px solid rgba(255,255,255,.1)}.admin-table th{color:var(--text-muted);font-weight:600;text-transform:uppercase;font-size:.75rem;letter-spacing:.5px}.admin-table td{color:var(--text-secondary)}.admin-table tr:hover td{background:#ffffff05}.loading-spinner{text-align:center;padding:var(--space-xl);color:var(--text-muted)}.admin-error{text-align:center;padding:var(--space-xl);background:#c0392b1a;border-radius:var(--radius-lg)}.admin-error p{color:#e74c3c;margin-bottom:var(--space-lg)}.hidden{display:none!important}.text-center{text-align:center}.text-muted{color:var(--text-muted)}