:root{--paper:#f4f2e9;--surface:#fffef9;--ink:#213e3b;--teal:#116f68;--muted:#697b74;--line:#c9d3c9;--red:#b33340}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:system-ui,-apple-system,"Noto Sans TC",sans-serif;-webkit-tap-highlight-color:transparent}button,select{font:inherit;color:inherit}button{cursor:pointer;border:1px solid var(--line);background:var(--surface);border-radius:10px;min-height:44px;touch-action:manipulation}button:hover{background:#e8eee5}button:active{transform:translateY(1px)}button:focus-visible,select:focus-visible{outline:3px solid #d1a64d;outline-offset:2px}button:disabled{opacity:.45;cursor:default}button.primary{background:var(--teal);color:white;border-color:var(--teal)}[hidden]{display:none!important}.app{width:min(100% - 32px,440px);margin:0 auto;padding:22px 0 max(16px,env(safe-area-inset-bottom));position:relative}header{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.eyebrow{font-size:10px;letter-spacing:.19em;color:var(--teal);margin:0 0 6px;font-weight:700}h1{font-family:serif;font-size:32px;margin:0;letter-spacing:.12em}h1 span{font-family:system-ui;font-size:12px;letter-spacing:.03em;font-weight:400;color:var(--muted);margin-left:8px}.round{border-radius:50%;width:44px;font-family:serif;font-size:20px}.topbar{display:flex;justify-content:space-between;align-items:center;gap:8px}.difficulty-label{display:flex;align-items:center;font-size:12px;color:var(--muted);gap:10px}select{border:0;background:transparent;font-size:14px;min-height:44px;max-width:200px;font-weight:600}#new{padding:0 15px;font-size:13px}.stats{display:flex;align-items:center;justify-content:space-between;font-size:12px;color:var(--muted);margin:7px 0 9px}#tier-label{color:var(--teal);font-weight:650}.clock{display:flex;gap:8px;align-items:center}#time{font-variant-numeric:tabular-nums;letter-spacing:.08em}#pause{border:0;min-height:32px;width:32px;border-radius:50%;background:#e5e9df}.board-wrap{position:relative}#grid{display:grid;grid-template-columns:repeat(9,1fr);aspect-ratio:1;background:var(--ink);border:2px solid var(--ink);box-shadow:0 6px 18px #213e3b0a}.cell{min-height:0;aspect-ratio:1;border:0;border-right:1px solid var(--line);border-bottom:1px solid var(--line);border-radius:0;background:var(--surface);padding:0;color:var(--teal);font-size:clamp(21px,6vw,30px);font-weight:450;position:relative;font-variant-numeric:tabular-nums}.cell:nth-child(3n){border-right:2px solid var(--ink)}.cell:nth-child(9n){border-right:0}.cell:nth-child(n+19):nth-child(-n+27),.cell:nth-child(n+46):nth-child(-n+54){border-bottom:2px solid var(--ink)}.cell:nth-child(n+73){border-bottom:0}.cell.given{color:var(--ink);font-weight:750}.cell.peer{background:#edf1e8}.cell.same{background:#d2e7de}.cell.selected{background:#b5d9d0;box-shadow:inset 0 0 0 2px var(--teal);z-index:1}.cell.conflict{color:var(--red);background:#fbe3df}.cell.conflict.selected{box-shadow:inset 0 0 0 2px var(--red)}.notes{display:grid;grid-template-columns:repeat(3,1fr);width:100%;height:100%;padding:2px}.note{font-size:10px;font-weight:500;align-self:center;line-height:1;color:#526c63}#cover{position:absolute;inset:0;background:#edf1e8;display:flex;align-items:center;justify-content:center;flex-direction:column;z-index:3}.cover-symbol{font-size:32px;color:var(--teal)}#cover h2{font-family:serif;font-size:26px;margin:14px 0 0}#cover p{font-size:13px;color:var(--muted)}#cover button{padding:0 20px}#status{font-size:12px;color:var(--muted);margin:10px 0;min-height:18px;text-align:center}.tools{display:grid;grid-template-columns:repeat(4,1fr);gap:7px;margin-bottom:12px}.tools button{border-color:transparent;background:transparent;font-size:12px;min-height:52px;display:flex;flex-direction:column;align-items:center;justify-content:center;position:relative;gap:3px}.tools button span{font-size:21px;line-height:1}.tools button small{position:absolute;top:4px;right:13px;color:var(--teal);font-size:10px}#pencil[aria-pressed=true]{background:var(--teal);color:white}#pad{display:grid;grid-template-columns:repeat(5,1fr);gap:5px}#pad button{font-size:24px;height:52px;min-width:0;border-color:#bdcfc4;background:#e8eee4;color:var(--teal);border-radius:9px}footer{display:flex;align-items:center;justify-content:space-between;color:var(--muted);font-size:10px;margin-top:12px}footer button{background:transparent;border:0;min-height:36px;font-size:11px;padding:0 5px}dialog{width:min(100% - 32px,420px);padding:25px;border:1px solid var(--line);border-radius:18px;background:var(--surface);color:var(--ink);max-height:85dvh;overflow:auto;box-shadow:0 20px 90px #213e3b33}dialog::backdrop{background:#213e3b70}dialog h2{font-family:serif;font-size:24px;margin:0 0 15px}dialog p{font-size:14px;line-height:1.8}.muted{color:var(--muted)}.dialog-actions{display:flex;gap:10px;margin-top:24px}.dialog-actions button{flex:1;padding:0 10px}#help-close{width:100%;margin-top:8px}#victory{position:fixed;z-index:6;left:50%;top:50%;transform:translate(-50%,-50%);width:min(100% - 40px,370px);background:var(--surface);border:1px solid #9bb9aa;border-radius:18px;padding:30px;text-align:center;box-shadow:0 0 0 100vmax #213e3b66,0 20px 60px #213e3b33}#victory h2{font-family:serif;font-size:26px}#victory p{font-size:13px;color:var(--muted)}#victory button{padding:0 14px;margin:5px} @media(max-height:700px){.app{padding:4px 0 max(4px,env(safe-area-inset-bottom));width:min(100% - 28px,440px)}header{margin-bottom:0}header .eyebrow{display:none}h1{font-size:26px}h1 span{font-size:11px}.stats{height:24px;margin:0}#pause{min-height:24px;width:28px}#status{margin:2px 0}.tools{margin-bottom:4px}.tools button{min-height:44px}#pad button{height:44px;font-size:22px}footer{margin-top:2px}footer button{min-height:20px}#pad{gap:4px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}