*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--font-header: "Outfit", "Inter", sans-serif;--font-body: "Inter", sans-serif;--radius-sm: 6px;--radius-md: 12px;--radius-lg: 20px;--radius-full: 9999px;--ease: cubic-bezier(.16, 1, .3, 1);--duration-fast: .15s;--duration-med: .3s;--duration-slow: .5s;--bg-page: #0b0f19;--bg-panel: rgba(17, 24, 39, .6);--bg-panel-hover: rgba(31, 41, 55, .8);--bg-input: #0f172a;--border-default: rgba(255, 255, 255, .08);--border-subtle: rgba(255, 255, 255, .04);--border-strong: rgba(255, 255, 255, .2);--text-primary: #f8fafc;--text-secondary: #94a3b8;--text-muted: #64748b;--accent: #3b82f6;--accent-glow: rgba(59, 130, 246, .5);--success: #10b981;--warning: #f5a623;--error: #ef4444;--sq-light: #f0d9b5;--sq-dark: #b58863;--shadow-soft: 0 24px 80px rgba(0, 0, 0, .4);--shadow-card: 0 8px 32px rgba(0, 0, 0, .3);--hl-selected: rgba(59, 130, 246, .4);--hl-selected-ring: #3b82f6;--hl-valid: rgba(16, 185, 129, .25);--hl-valid-dot: #10b981;--hl-capture: rgba(239, 68, 68, .3);--hl-last-from: rgba(234, 179, 8, .25);--hl-last-to: rgba(234, 179, 8, .35);--hl-check: rgba(239, 68, 68, .5);--hl-check-ring: #ef4444}body.theme-midnight{--bg-page: radial-gradient(circle at 50% 50%, #1e1b4b 0%, #030712 100%);--bg-panel: rgba(15, 23, 42, .55);--bg-panel-hover: rgba(30, 41, 59, .7);--bg-input: rgba(15, 23, 42, .85);--border-default: rgba(99, 102, 241, .2);--border-subtle: rgba(99, 102, 241, .08);--border-strong: rgba(99, 102, 241, .4);--text-primary: #f8fafc;--text-secondary: #cbd5e1;--text-muted: #64748b;--accent: #6366f1;--accent-glow: rgba(99, 102, 241, .6);--sq-light: #e8e6e3;--sq-dark: #706e6b;--hl-selected: rgba(99, 102, 241, .4);--hl-selected-ring: #818cf8;--hl-valid: rgba(34, 211, 238, .3);--hl-valid-dot: #22d3ee;--hl-capture: rgba(239, 68, 68, .35)}body.theme-emerald{--bg-page: radial-gradient(circle at 50% 50%, #064e3b 0%, #022c22 100%);--bg-panel: rgba(2, 44, 34, .55);--bg-panel-hover: rgba(4, 120, 87, .2);--bg-input: rgba(2, 44, 34, .85);--border-default: rgba(52, 211, 153, .2);--border-subtle: rgba(52, 211, 153, .08);--border-strong: rgba(52, 211, 153, .4);--text-primary: #ecfdf5;--text-secondary: #a7f3d0;--text-muted: #047857;--accent: #34d399;--accent-glow: rgba(52, 211, 153, .6);--sq-light: #e6f4ea;--sq-dark: #1b4d3e;--hl-selected: rgba(52, 211, 153, .45);--hl-selected-ring: #34d399;--hl-valid: rgba(251, 191, 36, .3);--hl-valid-dot: #fbbf24;--hl-capture: rgba(239, 68, 68, .35)}body.theme-woodland{--bg-page: radial-gradient(circle at 50% 50%, #451a03 0%, #1c0a00 100%);--bg-panel: rgba(43, 27, 16, .65);--bg-panel-hover: rgba(120, 53, 4, .25);--bg-input: rgba(28, 10, 0, .85);--border-default: rgba(245, 158, 11, .18);--border-subtle: rgba(245, 158, 11, .06);--border-strong: rgba(245, 158, 11, .35);--text-primary: #fffbeb;--text-secondary: #fde68a;--text-muted: #d97706;--accent: #f59e0b;--accent-glow: rgba(245, 158, 11, .5);--sq-light: #f5f5f4;--sq-dark: #78350f;--hl-selected: rgba(245, 158, 11, .4);--hl-selected-ring: #fbbf24;--hl-valid: rgba(16, 185, 129, .3);--hl-valid-dot: #10b981;--hl-capture: rgba(239, 68, 68, .35)}body.theme-cyber{--bg-page: radial-gradient(circle at 50% 50%, #2e0854 0%, #09011a 100%);--bg-panel: rgba(15, 2, 33, .7);--bg-panel-hover: rgba(236, 72, 153, .15);--bg-input: rgba(9, 1, 26, .9);--border-default: rgba(236, 72, 153, .25);--border-subtle: rgba(236, 72, 153, .1);--border-strong: rgba(236, 72, 153, .5);--text-primary: #fff0f6;--text-secondary: #fbcfe8;--text-muted: #db2777;--accent: #ec4899;--accent-glow: rgba(236, 72, 153, .6);--sq-light: #1f0c3a;--sq-dark: #a1005b;--hl-selected: rgba(236, 72, 153, .45);--hl-selected-ring: #f472b6;--hl-valid: rgba(34, 211, 238, .35);--hl-valid-dot: #22d3ee;--hl-capture: rgba(239, 68, 68, .4)}body{font-family:var(--font-body);background:var(--bg-page);color:var(--text-primary);min-height:100vh;line-height:1.5;overflow-x:hidden;position:relative;-webkit-font-smoothing:antialiased}body:before{content:"";position:fixed;top:0;right:0;bottom:0;left:0;background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");pointer-events:none;z-index:0}.app-container{max-width:1200px;margin:0 auto;padding:0 24px 64px;position:relative;z-index:1}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border-strong);border-radius:4px}.app-header{position:sticky;top:0;z-index:100;background:#00000059;backdrop-filter:blur(16px) saturate(180%);-webkit-backdrop-filter:blur(16px) saturate(180%);border-bottom:1px solid var(--border-default);height:64px;display:flex;align-items:center;justify-content:space-between;padding:0 24px;margin:0 -24px}.logo{display:flex;align-items:center;gap:12px;-webkit-user-select:none;user-select:none}.logo-icon{font-size:1.5rem;color:#7c3aed;text-shadow:0 0 10px rgba(124,58,237,.55),0 0 24px rgba(124,58,237,.35)}.logo-text h1{color:var(--text-primary);background:linear-gradient(135deg,#a78bfa,#7c3aed 45%,#60a5fa);-webkit-background-clip:text;-webkit-text-fill-color:transparent;text-shadow:0 0 16px rgba(124,58,237,.25)}.logo-text h1{font-family:var(--font-header);font-size:1.25rem;font-weight:800;letter-spacing:-.5px;line-height:1}.logo-text span{font-size:.7rem;font-weight:600;color:var(--text-muted);letter-spacing:1.5px;text-transform:uppercase}.session-pill{display:inline-flex;align-items:center;gap:8px;min-height:32px;padding:6px 14px;border:1px solid var(--border-default);border-radius:var(--radius-full);background:#ffffff0a;color:var(--text-secondary);font-size:.75rem;font-weight:600;white-space:nowrap}.session-pill:before{content:"";width:6px;height:6px;border-radius:50%;background:var(--success);box-shadow:0 0 8px var(--success)}.header-actions{display:flex;align-items:center;gap:16px}.theme-picker{display:flex;align-items:center;gap:8px;font-size:.8rem;color:var(--text-secondary)}.theme-picker select{background:var(--bg-input);color:var(--text-primary);border:1px solid var(--border-default);border-radius:var(--radius-sm);padding:5px 10px;font-family:inherit;font-size:.8rem;cursor:pointer;outline:none;transition:border-color var(--duration-fast) ease}.theme-picker select:hover,.theme-picker select:focus{border-color:var(--border-strong)}.control-btn{display:flex;align-items:center;justify-content:center;width:34px;height:34px;border-radius:var(--radius-sm);border:1px solid var(--border-default);background:transparent;color:var(--text-secondary);cursor:pointer;transition:all var(--duration-fast) ease;font-size:.85rem}.control-btn:hover{color:var(--text-primary);border-color:var(--border-strong);background:var(--bg-panel-hover);transform:translateY(-1px)}.game-workspace{display:grid;grid-template-columns:1fr 340px;gap:40px;align-items:start;padding-top:32px}.board-section{display:flex;flex-direction:column;max-width:720px;width:100%}.board-toolbar{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px;padding:14px 18px;border:1px solid var(--border-default);border-radius:var(--radius-md);background:var(--bg-panel);box-shadow:var(--shadow-card);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}.board-toolbar-left{display:flex;align-items:center;gap:10px}.board-toolbar-title{color:var(--text-secondary);font-size:.8rem;font-weight:700;text-transform:uppercase;letter-spacing:1px}.mode-pill{font-size:.75rem;font-weight:600;color:var(--accent);background:#6366f126;padding:2px 8px;border-radius:var(--radius-sm)}.board-hint{font-size:.8rem;font-weight:500;color:var(--text-muted)}.board-wrapper{border:1px solid var(--border-default);border-radius:var(--radius-lg);padding:16px;background:var(--bg-panel);box-shadow:var(--shadow-soft);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px)}.chessboard-grid{display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);aspect-ratio:1 / 1;width:100%;border-radius:8px;overflow:hidden;box-shadow:0 8px 24px #0006}.square{position:relative;display:flex;align-items:center;justify-content:center;cursor:default;-webkit-user-select:none;user-select:none}.light-square{background:var(--sq-light)}.dark-square{background:var(--sq-dark)}.coord-label{position:absolute;font-size:.7rem;font-weight:700;opacity:.65;pointer-events:none;z-index:5}.coord-label.file-label{bottom:2px;right:4px}.coord-label.rank-label{top:2px;left:4px}.light-square .coord-label{color:var(--sq-dark)}.dark-square .coord-label{color:var(--sq-light)}.piece{width:90%;height:90%;object-fit:contain;cursor:grab;z-index:10;transition:transform var(--duration-fast) var(--ease);filter:drop-shadow(0 4px 6px rgba(0,0,0,.35))}.piece:hover{transform:scale(1.08) translateY(-2px)}.piece:active{cursor:grabbing;transform:scale(1.15)}.square.selected-square{background-color:var(--hl-selected);box-shadow:inset 0 0 0 3px var(--hl-selected-ring)}.square.valid-move{cursor:pointer}.square.valid-move:before{content:"";position:absolute;width:25%;height:25%;border-radius:50%;background:var(--hl-valid-dot);box-shadow:0 0 10px var(--hl-valid-dot);z-index:12;pointer-events:none;animation:pulse-glow 2s infinite ease-in-out}.square.valid-capture{cursor:pointer;background-color:var(--hl-capture)}.square.valid-capture:before{content:"";position:absolute;top:6px;right:6px;bottom:6px;left:6px;border:3px solid var(--error);border-radius:50%;pointer-events:none;z-index:12}.square.last-move-from{background:var(--hl-last-from)}.square.last-move-to{background:var(--hl-last-to)}.square.check-square{background:var(--hl-check)!important;box-shadow:inset 0 0 0 3px var(--hl-check-ring)}.sidebar-section{display:flex;flex-direction:column;gap:20px;position:sticky;top:96px}.info-card{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);padding:20px;box-shadow:var(--shadow-card);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}.turn-w,.turn-b{display:flex;align-items:center;gap:12px;font-size:.9rem;font-weight:600}.turn-dot{width:10px;height:10px;border-radius:50%;background:var(--text-muted);transition:all var(--duration-med) ease}.turn-w .turn-dot{background:#fff;box-shadow:0 0 8px #fff}.turn-b .turn-dot{background:#475569;box-shadow:0 0 8px #475569}.scoreboard{display:flex;flex-direction:column;gap:16px}.captured-group{display:flex;flex-direction:column;gap:8px}.captured-title{font-size:.75rem;font-weight:700;color:var(--text-muted);text-transform:uppercase;letter-spacing:.5px}.captured-pieces{display:flex;flex-wrap:wrap;align-items:center;gap:4px;min-height:24px}.empty-captured{font-size:.8rem;color:var(--text-muted);font-style:italic}.captured-piece-icon{width:22px;height:22px;object-fit:contain;filter:drop-shadow(0 2px 4px rgba(0,0,0,.3))}.divider{height:1px;background:var(--border-subtle)}.advantage-row{display:flex;align-items:center;justify-content:space-between;font-size:.8rem;font-weight:600}.advantage-badge{background:var(--bg-input);border:1px solid var(--border-default);padding:3px 10px;border-radius:var(--radius-full)}.advantage-meter{height:6px;background:var(--bg-input);border-radius:var(--radius-full);overflow:hidden;position:relative}.advantage-meter-fill{position:absolute;top:0;left:0;height:100%;width:50%;background:var(--accent);box-shadow:0 0 8px var(--accent);transition:width var(--duration-med) var(--ease)}.history-card h3{font-family:var(--font-header);font-size:.95rem;font-weight:700;margin-bottom:12px;display:flex;align-items:center;gap:8px;color:var(--text-secondary)}.history-list{max-height:200px;overflow-y:auto;padding-right:4px;display:flex;flex-direction:column;gap:6px}.history-row{display:grid;grid-template-columns:40px 1fr 1fr;font-size:.85rem;padding:4px 8px;border-radius:var(--radius-sm);background:#ffffff05}.history-row:nth-child(2n){background:#ffffff0a}.empty-history{font-size:.8rem;color:var(--text-muted);text-align:center;padding:16px 0}.action-buttons{display:flex;gap:12px}.action-btn{flex:1;min-height:40px;display:flex;align-items:center;justify-content:center;gap:8px;border-radius:var(--radius-md);font-family:inherit;font-size:.85rem;font-weight:600;cursor:pointer;transition:all var(--duration-fast) ease}.action-btn.primary{background:var(--accent);color:#fff;border:none;box-shadow:0 4px 14px var(--accent-glow)}.action-btn.primary.header-play-btn{border:1px solid var(--border-strong)}.action-btn.primary.header-play-btn:hover:not(:disabled){border-color:var(--accent)}.action-btn.primary:hover:not(:disabled){background:#4f46e5;transform:translateY(-1px);box-shadow:0 6px 20px var(--accent-glow)}.action-btn.secondary{background:transparent;color:var(--text-secondary);border:1px solid var(--border-default)}.action-btn.secondary:hover:not(:disabled){color:var(--text-primary);border-color:var(--border-strong);background:var(--bg-panel-hover);transform:translateY(-1px)}.action-btn:disabled{opacity:.4;cursor:not-allowed;transform:none!important}.quick-links-bar{margin-top:40px}.quick-links-title{font-family:var(--font-header);font-size:1.1rem;font-weight:700;color:var(--text-secondary);margin-bottom:16px;text-align:center}.quick-links-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}.quick-link-card{display:flex;align-items:center;gap:14px;padding:18px 20px;background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);text-decoration:none;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);transition:all var(--duration-fast) ease}.quick-link-card:hover{border-color:var(--accent);background:var(--bg-panel-hover);transform:translateY(-2px);box-shadow:0 8px 24px #0003}.quick-link-card i{font-size:1.3rem;color:var(--accent);flex-shrink:0;width:36px;height:36px;display:flex;align-items:center;justify-content:center;background:#6366f11f;border-radius:var(--radius-sm)}.quick-link-label{display:block;font-size:.85rem;font-weight:700;color:var(--text-primary);margin-bottom:2px}.quick-link-desc{display:block;font-size:.72rem;color:var(--text-muted);line-height:1.4}.seo-content-section{margin-top:48px;padding:36px 40px;clear:both}.seo-title{font-family:var(--font-header);font-size:1.75rem;font-weight:800;margin-bottom:8px;background:linear-gradient(135deg,var(--text-primary),var(--text-secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent;letter-spacing:-.5px}.seo-content-section>.seo-title:after{content:"";display:block;width:60px;height:3px;margin-top:12px;border-radius:2px;background:var(--accent);opacity:.7}.seo-grid{display:grid;grid-template-columns:1fr 1fr;gap:32px;margin-top:28px}.seo-card{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);padding:28px 24px;display:flex;flex-direction:column;gap:16px;transition:border-color .25s ease,box-shadow .25s ease}.seo-card:hover{border-color:var(--border-strong);box-shadow:0 4px 20px #0003}.seo-card-title{font-family:var(--font-header);font-size:1.15rem;font-weight:700;color:var(--text-primary);margin:0}.seo-card>p{font-size:.875rem;color:var(--text-secondary);line-height:1.7}.seo-card>p strong{color:var(--text-primary);font-weight:600}.seo-list{display:flex;flex-direction:column;gap:10px;padding-left:20px;margin:8px 0}.seo-list li{font-size:.875rem;color:var(--text-secondary);line-height:1.6}.seo-list li strong{color:var(--text-primary)}.seo-features-list{list-style:none;display:flex;flex-direction:column;gap:10px;padding-left:0;margin:8px 0}.seo-features-list li{font-size:.875rem;color:var(--text-secondary);display:flex;align-items:flex-start;gap:10px;line-height:1.6}.seo-features-list li strong{color:var(--text-primary)}.seo-features-list li:before{content:"✓";color:var(--accent);font-weight:700;flex-shrink:0;margin-top:1px}.seo-accordion{border:1px solid var(--border-subtle);border-radius:var(--radius-sm);overflow:hidden}.seo-accordion+.seo-accordion{margin-top:8px}.seo-accordion summary{font-family:var(--font-header);font-size:.85rem;font-weight:600;color:var(--text-primary);padding:12px 16px;cursor:pointer;list-style:none;display:flex;align-items:center;gap:10px;background:var(--bg-panel);transition:background .2s ease;-webkit-user-select:none;user-select:none}.seo-accordion summary::-webkit-details-marker{display:none}.seo-accordion summary:before{content:"";width:6px;height:6px;border-right:2px solid var(--accent);border-bottom:2px solid var(--accent);transform:rotate(-45deg);transition:transform .2s ease;flex-shrink:0}.seo-accordion[open] summary:before{transform:rotate(45deg)}.seo-accordion summary:hover{background:var(--bg-panel-hover)}.seo-accordion>p,.seo-accordion>ul{padding:12px 16px 16px 32px;font-size:.85rem;color:var(--text-secondary);line-height:1.7}.seo-accordion>p strong{color:var(--text-primary);font-weight:600}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#000000a6;backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);display:flex;align-items:center;justify-content:center;padding:24px;z-index:500;opacity:0;pointer-events:none;transition:opacity var(--duration-med) ease}.modal-overlay.active{opacity:1;pointer-events:all}.modal-card{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-lg);padding:32px;width:100%;max-width:480px;box-shadow:var(--shadow-soft);animation:zoom-in var(--duration-med) var(--ease)}@keyframes zoom-in{0%{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}.config-card h2{font-family:var(--font-header);font-size:1.5rem;font-weight:800;letter-spacing:-.5px;margin-bottom:8px}.config-subtitle{font-size:.9rem;color:var(--text-secondary);margin-bottom:4px}.config-description{font-size:.8rem;color:var(--text-muted);margin-bottom:24px}.form-group{margin-bottom:24px}.group-label{display:block;font-size:.8rem;font-weight:700;color:var(--text-secondary);margin-bottom:12px;text-transform:uppercase;letter-spacing:.5px}.radio-toggle-group{display:grid;grid-template-columns:1fr 1fr;gap:16px}.radio-toggle input[type=radio]{display:none}.toggle-card{border:1px solid var(--border-default);background:var(--bg-input);border-radius:var(--radius-md);padding:16px;text-align:center;cursor:pointer;display:flex;flex-direction:column;align-items:center;gap:8px;transition:all var(--duration-fast) ease}.toggle-card i{font-size:1.5rem;color:var(--text-muted);transition:color var(--duration-fast) ease}.toggle-card span{font-size:.85rem;font-weight:700}.toggle-card small{font-size:.75rem;color:var(--text-muted)}.radio-toggle input[type=radio]:checked+.toggle-card{border-color:var(--accent);box-shadow:0 0 12px var(--accent-glow);background:var(--bg-panel-hover)}.radio-toggle input[type=radio]:checked+.toggle-card i{color:var(--accent)}.hidden{display:none!important}.sub-group{margin-top:20px}.color-select-group{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.color-option input[type=radio]{display:none}.color-card{border:1px solid var(--border-default);background:var(--bg-input);padding:10px;border-radius:var(--radius-sm);text-align:center;font-size:.8rem;font-weight:700;cursor:pointer;transition:all var(--duration-fast) ease}.color-option input[type=radio]:checked+.color-card{border-color:var(--accent);background:var(--bg-panel-hover);box-shadow:0 0 8px var(--accent-glow)}.label-row{display:flex;align-items:center;justify-content:space-between;margin-bottom:8px}.difficulty-badge{background:var(--accent);color:#fff;font-size:.75rem;font-weight:700;padding:2px 8px;border-radius:var(--radius-full)}.slider-input{width:100%;accent-color:var(--accent);height:6px;border-radius:var(--radius-full);outline:none;cursor:pointer}.slider-ticks{display:flex;justify-content:space-between;font-size:.7rem;color:var(--text-muted);margin-top:6px}.modal-submit-btn{width:100%;min-height:44px;background:var(--accent);color:#fff;border:none;border-radius:var(--radius-md);font-family:inherit;font-size:.9rem;font-weight:700;cursor:pointer;box-shadow:0 4px 14px var(--accent-glow);display:flex;align-items:center;justify-content:center;gap:8px;transition:all var(--duration-fast) ease}.modal-submit-btn:hover{background:#4f46e5;transform:translateY(-1px);box-shadow:0 6px 20px var(--accent-glow)}.promotion-card{max-width:360px;text-align:center}.promotion-card h3{font-family:var(--font-header);font-size:1.25rem;margin-bottom:8px}.promotion-card p{font-size:.85rem;color:var(--text-secondary);margin-bottom:20px}.promotion-options{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.promotion-btn{border:1px solid var(--border-default);background:var(--bg-input);border-radius:var(--radius-md);padding:10px;cursor:pointer;transition:all var(--duration-fast) ease;display:flex;align-items:center;justify-content:center}.promotion-btn:hover{border-color:var(--accent);background:var(--bg-panel-hover);transform:translateY(-2px)}.promotion-btn img{width:100%;height:100%;object-fit:contain}.game-over-card{max-width:360px;text-align:center}.trophy-icon{font-size:3rem;color:var(--accent);margin-bottom:16px;animation:animate-float 2s ease-in-out infinite}#gameOverText h2{font-family:var(--font-header);font-size:1.5rem;font-weight:800;margin-bottom:8px}#gameOverText p{font-size:.85rem;color:var(--text-secondary);margin-bottom:24px}.toast-container{position:fixed;bottom:24px;right:24px;z-index:1000;display:flex;flex-direction:column;gap:10px;pointer-events:none}.toast{background:var(--bg-panel);border:1px solid var(--border-strong);color:var(--text-primary);padding:12px 24px;border-radius:var(--radius-md);font-size:.85rem;font-weight:600;box-shadow:var(--shadow-soft);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);pointer-events:all;animation:slide-in var(--duration-med) var(--ease)}@keyframes slide-in{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes pulse-glow{0%,to{transform:scale(1);opacity:.8}50%{transform:scale(1.15);opacity:1;box-shadow:0 0 14px var(--hl-valid-dot)}}@keyframes animate-float{0%,to{transform:translateY(0)}50%{transform:translateY(-6px)}}.animate-float{animation:animate-float 3s ease-in-out infinite}.header-nav{display:flex;align-items:center;gap:24px}.header-nav a{color:var(--text-secondary);text-decoration:none;font-size:.85rem;font-weight:600;letter-spacing:.3px;transition:color var(--duration-fast) ease;position:relative}.header-nav a:after{content:"";position:absolute;bottom:-4px;left:0;width:0;height:2px;background:var(--accent);border-radius:1px;transition:width var(--duration-med) var(--ease)}.header-nav a:hover,.header-nav a.active{color:var(--text-primary)}.header-nav a:hover:after,.header-nav a.active:after{width:100%}.header-play-btn{text-decoration:none;font-family:inherit}.app-footer{margin-top:64px;border-top:1px solid var(--border-default);padding:48px 0 0}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:40px;margin-bottom:40px}.footer-brand .logo{margin-bottom:12px}.footer-tagline{font-size:.85rem;color:var(--text-muted);line-height:1.6;max-width:320px}.footer-links h4{font-family:var(--font-header);font-size:.8rem;font-weight:700;color:var(--text-secondary);text-transform:uppercase;letter-spacing:1px;margin-bottom:16px}.footer-links ul{list-style:none;display:flex;flex-direction:column;gap:10px}.footer-links a{color:var(--text-muted);text-decoration:none;font-size:.85rem;transition:color var(--duration-fast) ease}.footer-links a:hover{color:var(--text-primary)}.footer-bottom{border-top:1px solid var(--border-subtle);padding:20px 0;text-align:center}.footer-bottom p{font-size:.75rem;color:var(--text-muted)}.page-content{max-width:860px;margin:0 auto;padding:48px 0}.page-article{display:flex;flex-direction:column;gap:32px}.page-title{font-family:var(--font-header);font-size:2rem;font-weight:800;letter-spacing:-.5px;background:linear-gradient(135deg,var(--text-primary),var(--text-secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent}.page-subtitle{font-size:1.05rem;color:var(--text-secondary);line-height:1.6;margin-top:-20px}.page-updated{font-size:.8rem;color:var(--text-muted);margin-top:-24px}.page-section{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);padding:28px 32px;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}.page-section h2{font-family:var(--font-header);font-size:1.2rem;font-weight:700;color:var(--text-primary);margin-bottom:14px}.page-section h3{font-size:.95rem;font-weight:600;color:var(--text-primary);margin-top:16px;margin-bottom:8px}.page-section p{font-size:.9rem;color:var(--text-secondary);line-height:1.7;margin-bottom:12px}.page-section p:last-child{margin-bottom:0}.page-section ul{padding-left:20px;margin-bottom:12px}.page-section li{font-size:.9rem;color:var(--text-secondary);line-height:1.7;margin-bottom:6px}.page-section li strong{color:var(--text-primary)}.page-section a{color:var(--accent);text-decoration:none;font-weight:600;transition:opacity var(--duration-fast) ease}.page-section a:hover{opacity:.8}.about-features-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.about-feature-card{background:var(--bg-input);border:1px solid var(--border-subtle);border-radius:var(--radius-md);padding:24px;transition:border-color var(--duration-fast) ease}.about-feature-card:hover{border-color:var(--border-strong)}.about-feature-card i{font-size:1.5rem;color:var(--accent);margin-bottom:12px;display:block}.about-feature-card h3{font-family:var(--font-header);font-size:1rem;font-weight:700;color:var(--text-primary);margin-bottom:8px}.about-feature-card p{font-size:.85rem;color:var(--text-secondary);line-height:1.6}.contact-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:32px;align-items:start}.contact-form-section h2,.contact-info-section h2{font-family:var(--font-header);font-size:1.2rem;font-weight:700;color:var(--text-primary);margin-bottom:20px}.contact-form{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);padding:28px 32px;display:flex;flex-direction:column;gap:18px;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}.form-field{display:flex;flex-direction:column;gap:6px}.form-field label{font-size:.8rem;font-weight:600;color:var(--text-secondary);text-transform:uppercase;letter-spacing:.5px}.form-field input,.form-field select,.form-field textarea{background:var(--bg-input);color:var(--text-primary);border:1px solid var(--border-default);border-radius:var(--radius-sm);padding:10px 14px;font-family:inherit;font-size:.9rem;outline:none;transition:border-color var(--duration-fast) ease;resize:vertical}.form-field input::placeholder,.form-field textarea::placeholder{color:var(--text-muted)}.form-field input:focus,.form-field select:focus,.form-field textarea:focus{border-color:var(--accent)}.contact-submit{margin-top:4px}.contact-info-cards{display:flex;flex-direction:column;gap:14px}.contact-info-card{background:var(--bg-panel);border:1px solid var(--border-default);border-radius:var(--radius-md);padding:20px 24px;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px)}.contact-info-card i{font-size:1.2rem;color:var(--accent);margin-bottom:8px}.contact-info-card h3{font-family:var(--font-header);font-size:.95rem;font-weight:700;color:var(--text-primary);margin-bottom:4px}.contact-info-card p{font-size:.8rem;color:var(--text-muted);margin-bottom:6px}.contact-info-card a{font-size:.85rem;color:var(--accent);text-decoration:none;font-weight:600;transition:opacity var(--duration-fast) ease}.contact-info-card a:hover{opacity:.8}.faq-section{margin-top:16px}.faq-list{display:flex;flex-direction:column;gap:8px}.faq-item{border:1px solid var(--border-subtle);border-radius:var(--radius-sm);background:var(--bg-input);overflow:hidden}.faq-item summary{padding:14px 18px;font-size:.9rem;font-weight:600;color:var(--text-primary);cursor:pointer;list-style:none;display:flex;align-items:center;gap:10px;transition:color var(--duration-fast) ease}.faq-item summary:before{content:"";font-family:"Font Awesome 6 Free";font-weight:900;font-size:.7rem;color:var(--text-muted);transition:transform var(--duration-med) var(--ease)}.faq-item[open] summary:before{transform:rotate(90deg)}.faq-item summary::-webkit-details-marker{display:none}.faq-item p{padding:0 18px 14px;font-size:.85rem;color:var(--text-secondary);line-height:1.6}@media(max-width:1024px){.app-container{padding:0 20px 56px}.game-workspace{grid-template-columns:1fr 280px;gap:28px}}@media(max-width:900px){.header-nav{display:none}.quick-links-grid{grid-template-columns:1fr 1fr}.contact-grid,.about-features-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr;gap:28px}.app-container{padding:0 16px 48px}.app-header{margin:0 -16px;padding:0 16px}.game-workspace{grid-template-columns:1fr;gap:20px;padding-top:20px}.board-section{max-width:100%}.sidebar-section{position:static;gap:14px}.history-list{max-height:220px}.action-buttons{gap:10px}.seo-grid{grid-template-columns:1fr;gap:20px}.seo-content-section{margin-top:32px;padding:24px 20px}.seo-card{padding:22px 20px}}@media(max-width:768px){.app-header{height:52px;padding:0 14px;margin:0 -16px}.theme-picker label i+span,.theme-picker>label>span{display:none}.board-wrapper{padding:10px;border-radius:16px}.chessboard-grid{border-radius:10px}.info-card{padding:14px 16px}.history-list{max-height:180px}.modal-overlay{align-items:flex-start;overflow-y:auto;padding:16px}.modal-card{padding:24px 20px;margin:auto}}@media(max-width:480px){.page-content{padding:24px 0}.page-title{font-size:1.6rem}.page-section,.contact-form{padding:20px 18px}.app-footer{margin-top:40px}.app-container{padding:0 12px 40px}.app-header{height:50px;margin:0 -12px;padding:0 12px}.logo-text h1{font-size:.95rem}.logo-text span{font-size:.6rem;letter-spacing:1px}.theme-picker label{display:none}.theme-picker{gap:0}.board-wrapper{padding:8px;border-radius:14px}.chessboard-grid{border-radius:8px}.info-card{padding:12px 14px}.history-list{max-height:160px}.history-row{font-size:.75rem;padding:4px 2px}.action-buttons{flex-direction:column;gap:8px}.modal-card{padding:20px 16px;border-radius:var(--radius-md)}.config-card h2{font-size:1.15rem;margin-bottom:18px}.radio-toggle-group{grid-template-columns:1fr;gap:8px}.toggle-card{flex-direction:row;gap:10px;padding:12px;text-align:left;align-items:center}.toggle-card i{font-size:1rem;flex-shrink:0}.promotion-options{grid-template-columns:repeat(2,1fr);gap:12px}.game-over-card{max-width:100%}.trophy-icon{font-size:2.4rem;margin-bottom:14px}#game-over-text h2{font-size:1.25rem}.seo-title{font-size:1.4rem;margin-bottom:8px}.seo-content-section>.seo-title:after{width:48px;margin-top:10px}.seo-content-section{margin-top:24px;padding:20px 16px}.seo-card{padding:20px 16px}.seo-accordion summary{padding:10px 14px;font-size:.82rem}.seo-accordion>p,.seo-accordion>ul{padding:10px 14px 14px 28px;font-size:.82rem}.quick-links-grid{grid-template-columns:1fr;gap:10px}.quick-link-card{padding:14px 16px}}@media(max-width:380px){.app-container{padding:0 10px 32px}.app-header{margin:0 -10px;padding:0 10px}.logo-text span{display:none}.board-wrapper{padding:5px;border-radius:10px}.chessboard-grid{border-radius:6px}.modal-card{padding:16px 12px}.slider-ticks span:nth-child(2),.slider-ticks span:nth-child(4){display:none}.color-card{padding:8px 4px;font-size:.75rem}.history-list{max-height:140px}.seo-title{font-size:1.25rem;margin-bottom:6px}.seo-content-section>.seo-title:after{width:40px;margin-top:8px}.seo-content-section{margin-top:18px;padding:14px 10px}.seo-card{padding:16px 12px}}