:root{--bg: #0d1117;--panel: #161b22;--ink: #e6edf3;--muted: #8b949e;--accent: #58a6ff;--accel: #f0883e;--scenery: #6e7681;--good: #3fb950;--bad: #f85149;--line: #30363d}*{box-sizing:border-box}html,body{margin:0;height:100%;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;-webkit-user-select:none;user-select:none;overflow:hidden}#app{display:flex;flex-direction:column;height:100vh}.topbar{display:flex;align-items:center;gap:12px;padding:8px 14px;background:var(--panel);border-bottom:1px solid var(--line);flex-wrap:wrap}.title{font-weight:700;font-size:18px;letter-spacing:.5px;margin-right:6px}.title small{color:var(--muted);font-weight:400;font-size:12px;margin-left:6px}.spacer{flex:1}button,select{background:#21262d;color:var(--ink);border:1px solid var(--line);border-radius:6px;padding:6px 12px;font-size:14px;cursor:pointer;transition:background .12s ease,border-color .12s ease}button:hover,select:hover{background:#30363d}button:active{transform:translateY(1px)}button.primary{background:var(--accent);border-color:var(--accent);color:#0d1117;font-weight:600}button.primary.stop{background:var(--bad);border-color:var(--bad);color:#fff}button.active{outline:2px solid var(--accent);outline-offset:-2px}.tools{display:flex;gap:6px;align-items:center}.tool-swatch{display:inline-block;width:12px;height:12px;border-radius:2px;margin-right:6px;vertical-align:middle}.sw-solid{background:var(--accent)}.sw-accel{background:var(--accel)}.sw-scenery{background:var(--scenery)}.sw-eraser{background:var(--bad)}.sw-flag{background:var(--good)}.sw-goal{background:#58ffa6}.hud{display:flex;gap:16px;font-size:13px;color:var(--muted)}.hud b{color:var(--ink)}.hud .ink-low{color:var(--bad)}.stage{flex:1;position:relative;overflow:hidden}canvas{display:block;width:100%;height:100%;background:#0a0e14;cursor:crosshair;touch-action:none}.banner{position:absolute;top:18px;left:50%;transform:translate(-50%);padding:8px 18px;border-radius:8px;font-weight:600;font-size:16px;background:var(--panel);border:1px solid var(--line);box-shadow:0 4px 16px #0006;pointer-events:none;opacity:0;transition:opacity .2s ease}.banner.show{opacity:1}.banner.win{border-color:var(--good);color:var(--good)}.banner.crash{border-color:var(--bad);color:var(--bad)}.hint{position:absolute;bottom:12px;left:12px;font-size:12px;color:var(--muted);pointer-events:none;max-width:60%}