:root{color-scheme:dark;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:#101b24;color:#edf8f5}*{box-sizing:border-box}body{margin:0;min-height:100vh;background:radial-gradient(circle at 90% 0%,#244451 0%,#101b24 44%)}.chess-shell{width:min(100% - 28px,990px);margin:auto;padding:24px 0 48px}.back{color:#83e5d0;text-decoration:none;font:700 .72rem ui-monospace,monospace;letter-spacing:.13em}.back:hover{text-decoration:underline}header{text-align:center;margin:38px 0 25px}.eyebrow{color:#84dccb;letter-spacing:.21em;font:700 .66rem ui-monospace,monospace}h1{font-size:clamp(3.3rem,11vw,6.8rem);letter-spacing:-.055em;line-height:1;margin:.15em 0}h1 span{display:inline-block;color:#8ee8d2;margin-left:.16em;font-weight:400}.subtitle{color:#aac5c0;margin:.6rem 0 0}.chess-game{width:min(100%,620px);margin:auto}.player{display:flex;align-items:center;gap:12px;padding:12px 4px}.player small{display:block;font:700 .64rem ui-monospace,monospace;letter-spacing:.15em;color:#8eaaa6}.player strong{font-size:1rem;overflow-wrap:anywhere}.marker{width:33px;height:33px;border-radius:50%;display:grid;place-items:center;border:2px solid #a0b8b2}.marker.light{color:#f1e8d6;background:#f1e8d6}.marker.dark{color:#182b35;background:#182b35}.board{display:grid;grid-template-columns:repeat(8,1fr);width:100%;aspect-ratio:1;border:6px solid #34505a;box-shadow:0 18px 44px #050d14aa}.square{border:0;padding:0;display:grid;place-items:center;aspect-ratio:1;cursor:pointer;position:relative;font-size:clamp(1.8rem,7vw,3.35rem);line-height:1;touch-action:manipulation}.square.light{background:#c6ddd5}.square.dark{background:#739894}.square.selected{background:#f4c67c}.square:focus-visible{outline:3px solid #ed7d64;outline-offset:-3px;z-index:2}.piece-white{color:#fffaf0;text-shadow:0 2px 1px #52676a,1px 0 1px #52676a,-1px 0 1px #52676a}.piece-black{color:#162932;text-shadow:0 1px 1px #b4d1cd}.square .coord{position:absolute;bottom:3px;right:3px;font:600 .56rem ui-monospace,monospace;opacity:.65;color:#10252b}.chess-info{width:min(100%,620px);margin:20px auto 0;background:#192e38;border:1px solid #395963;padding:18px 20px}#status{font-size:1.05rem;font-weight:700;margin:0 0 .5rem;color:#93ead5}#status.error{color:#ffb29c}#last-move{color:#efc77d;margin:.3rem 0}.help{font-size:.8rem;line-height:1.5;color:#a9c2be;margin-top:1rem}footer{text-align:center;color:#769a99;margin:2rem auto;font:600 .63rem ui-monospace,monospace;letter-spacing:.1em;line-height:1.7}@media(max-width:520px){.chess-shell{padding-top:17px}.board{border-width:4px}.square{font-size:clamp(1.55rem,9vw,2.8rem)}.chess-info{padding:15px}header{margin-top:28px}}