*{box-sizing:border-box}html{color-scheme:dark}body{margin:0;background:radial-gradient(ellipse at top,#23364d,#0d1524);color:#eff6ff;font:16px/1.5 system-ui,sans-serif}main{width:min(100%,600px);margin:auto;padding:16px}header{display:flex;align-items:center;gap:12px}header img{width:54px;height:54px}h1{font-size:clamp(24px,7vw,38px);line-height:1.1;margin:18px 0;overflow-wrap:anywhere}.eyebrow{color:#a9cfde;font-size:12px;letter-spacing:.15em;text-transform:uppercase}#status,#message{padding:12px;border:1px solid #496275;border-radius:12px;background:#142334;overflow-wrap:anywhere}#message{border-color:#71d7c1;min-height:48px}#board{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:6px;margin:14px 0}button,a,summary{min-height:48px;min-width:44px}button{border:1px solid #65889f;border-radius:10px;background:#263e57;color:#fff;font:inherit;padding:8px;cursor:pointer;touch-action:manipulation;overflow-wrap:anywhere;white-space:pre-line}button.tile{min-height:64px;padding:4px;font-size:14px;background:linear-gradient(145deg,#2f526b,#1d3247)}button:hover{background:#416783}button.selected{outline:3px solid #f5ce76;outline-offset:-3px}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #f5ce76;outline-offset:2px}button:disabled{opacity:.6;cursor:default}#actions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}details{margin-top:18px;border-top:1px solid #486175}summary{padding:12px 0;cursor:pointer}a{display:flex;align-items:center;color:#9cdeef;padding:8px 0;overflow-wrap:anywhere}footer{font-size:13px;color:#b5c7d5;margin-top:20px}@media(max-width:340px){main{padding:10px}button.tile{font-size:12px}}@media(prefers-reduced-motion:no-preference){button{transition:background .15s}}button.tile[data-tone="0"]{background:#743a4e}button.tile[data-tone="1"]{background:#215a73}button.tile[data-tone="2"]{background:#5c5629}button.tile[data-tone="3"]{background:#4f4278}
#board{grid-template-columns:repeat(2,minmax(0,1fr))}#board button{min-height:130px;white-space:pre-line;line-height:1.45}

/* Static puzzle cells remain readable; unavailable actions remain dimmed. */
#board button:disabled{opacity:1;cursor:default}