:root{--bg: #0d1318;--panel: #172029;--line: #283744;--ink: #eef4f8;--dim: #8ea3b4;--accent: #3a7fb0;--good: #2e9e6a;--bad: #b0433a;--valid: #1d3a4d}*{box-sizing:border-box}html,body{margin:0;height:100%}body{background:radial-gradient(900px 560px at 50% -8%,#15222e,var(--bg));color:var(--ink);font-family:system-ui,-apple-system,Segoe UI,sans-serif;display:flex;justify-content:center;-webkit-user-select:none;user-select:none}#app{width:100%;max-width:540px;padding:12px 12px 26px}header{text-align:center;margin-bottom:6px}h1{margin:0;font-size:27px;letter-spacing:5px;font-weight:800;color:var(--accent)}.sub{margin:4px 0 0;color:var(--dim);font-size:12.5px;line-height:1.4}.bar{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;align-items:center;margin:10px 0}.seg{display:inline-flex;background:var(--panel);border:1px solid var(--line);border-radius:999px;overflow:hidden}.seg button{background:none;border:none;color:var(--dim);padding:6px 13px;font:600 13px system-ui;cursor:pointer}.seg button.active{background:var(--accent);color:#04141f}.btn{background:var(--panel);border:1px solid var(--line);color:var(--ink);padding:7px 14px;border-radius:999px;font:700 13px system-ui;cursor:pointer}.btn:hover{border-color:var(--accent)}.btn.primary{background:var(--accent);color:#04141f;border-color:var(--accent)}.targetbar{display:flex;align-items:center;justify-content:center;gap:12px;margin:8px 0 4px}.modechip{background:var(--panel);border:1px solid var(--line);color:var(--dim);border-radius:999px;padding:5px 12px;font:700 12px system-ui;letter-spacing:1px}.target{font:800 40px ui-monospace,monospace;color:var(--accent);min-width:56px;text-align:center}.goalhint{color:var(--dim);font-size:12px;min-width:70px}.scoreboard{display:flex;gap:10px;justify-content:center;margin:8px 0}.readout{background:#08111a;border:1px solid var(--line);border-radius:8px;padding:5px 16px;font:800 18px ui-monospace,monospace;color:var(--accent);min-width:86px;text-align:center}.readout span{color:var(--dim);font-size:11px;display:block;font-weight:600;letter-spacing:.5px}.stage{position:relative;display:flex;justify-content:center}.grid{display:grid;gap:4px;background:var(--line);border:2px solid var(--line);border-radius:8px;padding:4px;width:min(94vw,460px);aspect-ratio:1}.cell{position:relative;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:clamp(14px,5vw,24px);aspect-ratio:1;border-radius:5px;transition:background .1s,transform .06s}.cell.empty{background:transparent}.cell.num{background:#1f2c37;color:var(--ink);cursor:pointer;box-shadow:inset 0 0 0 1px #2b3b48}.cell.num:hover{background:#283845}.cell.num.valid{background:var(--valid);box-shadow:inset 0 0 0 2px var(--accent);color:#cfe6f3}.cell.num.valid:hover{background:#234a61}.cell.num.good{background:var(--good);color:#fff}.cell.num.bad{background:var(--bad);color:#fff}.overlay{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:#070c11cc;border-radius:8px;backdrop-filter:blur(3px)}.overlay.hidden{display:none}.card{background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:22px 26px;text-align:center;max-width:340px}.card h2{margin:0 0 6px;font-size:24px;color:var(--accent)}.card p{margin:6px 0;color:var(--dim);font-size:14px}.card p b{color:var(--ink)}.card .row{display:flex;gap:8px;justify-content:center;margin-top:14px}.hint{text-align:center;color:var(--dim);font-size:12px;margin-top:14px;line-height:1.5;min-height:18px}