:root{--bg: #1e1e24;--surface: #2a2a32;--text: #f0f0f0;--muted: #9a9aa8;--accent: #facb2e;--light-square: #eeeed1;--dark-square: #769656;--selected: rgba(217, 184, 46, .55);--last-move: rgba(217, 184, 46, .35);--legal-dot: rgba(30, 30, 30, .28);--capture-ring: rgba(217, 51, 38, .55);--check: rgba(220, 40, 40, .45);--frame: rgba(250, 203, 46, .25);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif}*{box-sizing:border-box}html,body{margin:0;min-height:100%;background:var(--bg);color:var(--text)}#app{min-height:100vh;display:flex;flex-direction:column}button{font:inherit;cursor:pointer;border:none;border-radius:10px;padding:12px 18px;background:var(--surface);color:var(--text);transition:background .15s,transform .1s}button:hover:not(:disabled){background:#363640}button:disabled{opacity:.45;cursor:not-allowed}button.primary{background:var(--accent);color:#1a1a1a;font-weight:600}button.primary:hover:not(:disabled){background:#ffd84d}button.danger{background:#5c2a2a;color:#ffb4b4}input,select{font:inherit;padding:10px 12px;border-radius:8px;border:1px solid #444;background:var(--bg);color:var(--text);width:100%}.home{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px;gap:20px;max-width:420px;margin:0 auto}.home-logo{width:72px;height:72px;border-radius:16px;display:block}.home h1{margin:0;font-size:1.75rem;text-align:center}.home .tagline{margin:0;color:var(--muted);text-align:center;font-size:.95rem;line-height:1.45}.home-actions{display:flex;flex-direction:column;gap:12px;width:100%}.difficulty-picker{display:flex;gap:8px;width:100%}.difficulty-picker button{flex:1;padding:10px}.difficulty-picker button.active{outline:2px solid var(--accent)}.settings-panel{width:100%;padding:16px;background:var(--surface);border-radius:12px;display:flex;flex-direction:column;gap:10px}.settings-panel label{font-size:.8rem;color:var(--muted)}.settings-toggle{background:transparent;color:var(--accent);padding:8px;font-size:.9rem}.engine-status{font-size:.85rem;color:var(--muted)}.engine-status.ok{color:#7dce82}.engine-status.err{color:#ff8a80}.game-screen{flex:1;display:flex;flex-direction:column;max-width:720px;margin:0 auto;width:100%;padding:8px 12px 16px}.game-header{display:flex;align-items:center;gap:12px;padding:8px 0}.game-header h2{flex:1;margin:0;font-size:1.1rem;font-weight:600}.game-header .back{padding:8px 12px}.game-header .auto-flip{font-size:.75rem;padding:6px 10px;white-space:nowrap;color:var(--muted)}.game-header .auto-flip.active{color:var(--accent)}.status-bar{text-align:center;font-size:.9rem;color:var(--muted);min-height:1.4em;margin-bottom:6px}.status-bar.error{color:#ff8a80}.captured-bar{display:flex;justify-content:space-between;align-items:flex-start;gap:6px;min-height:32px;max-width:100%;font-size:.85rem;color:var(--muted)}.captured-side{flex:1 1 0;min-width:0;max-width:calc(50% - 20px)}.captured-side-white .captured-pieces{justify-content:flex-end}.captured-pieces{display:flex;flex-wrap:wrap;gap:2px;align-content:flex-start}.captured-pieces img{width:24px;height:24px;flex:0 0 auto}.board-wrap{position:relative;width:100%;max-width:min(100vw - 24px,560px);margin:0 auto;aspect-ratio:1}.board-grid{display:grid;grid-template-columns:repeat(10,1fr);grid-template-rows:repeat(10,1fr);width:100%;height:100%;gap:0;border-radius:0;overflow:hidden;box-shadow:0 4px 24px #00000073}.board-frame{position:absolute;pointer-events:none;border:3px solid var(--frame);border-radius:0;top:10%;left:10%;width:80%;height:80%}.square{position:relative;display:flex;align-items:center;justify-content:center;border:none;border-radius:0;padding:0;margin:0;min-width:0;min-height:0;background:var(--light-square)}.square.dark{background:var(--dark-square)}.square.selected{background-color:var(--selected)!important}.square.last-move{background-color:var(--last-move)!important}.square.in-check{background-color:var(--check)!important}.square .piece-img{width:88%;height:88%;pointer-events:none;-webkit-user-select:none;user-select:none}.square .legal-dot{position:absolute;width:28%;height:28%;border-radius:50%;background:var(--legal-dot)}.square .capture-ring{position:absolute;top:8%;right:8%;bottom:8%;left:8%;border-radius:50%;border:4px solid var(--capture-ring);pointer-events:none}.coord{position:absolute;font-size:.55rem;font-weight:700;pointer-events:none;line-height:1}.square.light .coord{color:var(--dark-square);opacity:.9}.square.dark .coord{color:var(--light-square);opacity:.85}.coord.file{bottom:2px;right:3px}.coord.rank{top:2px;left:3px}.move-list-wrap{margin-top:12px;background:var(--surface);border-radius:10px;max-height:120px;overflow-y:auto}.move-list{display:flex;flex-wrap:wrap;gap:4px 8px;padding:10px 12px;font-size:.85rem;font-family:ui-monospace,SFMono-Regular,Menlo,monospace}.move-list .move-num{color:var(--muted);margin-right:2px}.move-list button.move-entry{padding:4px 8px;font-size:inherit;font-family:inherit;background:transparent}.move-list button.move-entry.active{background:#facb2e33;color:var(--accent)}.game-controls{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px;justify-content:center}.game-controls button{flex:1;min-width:80px}.overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#000000a6;display:flex;align-items:center;justify-content:center;z-index:100;padding:20px}.overlay-panel{background:var(--surface);border-radius:16px;padding:24px;max-width:340px;width:100%;text-align:center}.overlay-panel h3{margin:0 0 8px}.promotion-options{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:16px}.promotion-options button{aspect-ratio:1;padding:8px;background:var(--bg)}.promotion-options img{width:100%;height:100%}@media(min-width:600px){.game-screen{padding:16px 24px 24px}}