:root{--bg: #0e1116;--panel: #181d25;--line: #2a323d;--ink: #eef3f7;--dim: #93a4b3;--accent: #4a9cc0;--good: #2f6f4a;--bad: #6f2f37}*{box-sizing:border-box}html,body{margin:0;height:100%}body{background:radial-gradient(900px 560px at 50% -8%,#16202a,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 40px;position:relative}header{text-align:center;margin-bottom:6px}h1{margin:0;font-size:30px;letter-spacing:7px;font-weight:800;color:var(--accent)}.sub{margin:3px 0 0;color:var(--dim);font-size:13px}.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 15px;font:600 13px system-ui;cursor:pointer}.seg button.active{background:var(--accent);color:#05222c}.btn{background:var(--panel);border:1px solid var(--line);color:var(--ink);padding:8px 15px;border-radius:999px;font:700 13px system-ui;cursor:pointer}.btn:hover{border-color:var(--accent)}.btn.primary{background:var(--accent);color:#05222c;border-color:var(--accent)}.scoreboard{display:flex;gap:10px;justify-content:center;margin:8px 0}.readout{background:#0a0e13;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}.sporttag{display:inline-block;margin:4px auto 0;padding:3px 12px;border:1px solid var(--line);border-radius:999px;font:800 12px system-ui;letter-spacing:1px;text-transform:uppercase}.stage{position:relative;display:flex;justify-content:center;margin:8px 0}#diagram{width:min(94vw,440px);height:auto;border-radius:10px;border:1px solid var(--line);background:#0c1219}.prompt{font-size:15px;line-height:1.4;margin:10px 2px;min-height:44px}.options{display:grid;gap:8px}.opt{text-align:left;background:var(--panel);border:1px solid var(--line);color:var(--ink);padding:11px 14px;border-radius:10px;font:600 14px system-ui;cursor:pointer}.opt:hover:not(:disabled){border-color:var(--accent)}.opt:disabled{cursor:default;opacity:.92}.opt.right{background:var(--good);border-color:#3da06a}.opt.wrong{background:var(--bad);border-color:#a0414d}.feedback{margin:12px 2px;padding:10px 12px;border-radius:10px;font-size:13px;line-height:1.45;border:1px solid var(--line);background:var(--panel)}.feedback.good{border-color:#3da06a}.feedback.bad{border-color:#a0414d}#advancebtn{display:block;width:100%;margin-top:6px;padding:12px}.hidden{display:none!important}.overlay{position:fixed;inset:0;background:#060a0ed1;display:flex;align-items:center;justify-content:center;z-index:20}.card{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:26px 30px;text-align:center;max-width:320px}.card h2{margin:0 0 8px;color:var(--accent)}.card p{color:var(--dim);font-size:14px;line-height:1.7}.bigscore{font:800 46px ui-monospace,monospace;color:var(--accent);margin:8px 0}.card .btn{margin-top:10px}