:root {
      --bg: #0f172a; /* slate-900 */
      --card: #111827; /* gray-900 */
      --text: #e5e7eb; /* gray-200 */
      --muted: #9ca3af; /* gray-400 */
      --accent: #22c55e; /* green-500 */
      --accent-2: #3b82f6; /* blue-500 */
      --danger: #ef4444; /* red-500 */
      --border: #1f2937; /* gray-800 */
    }

    * { box-sizing: border-box; }
    html, body { height: 100%; margin: 0; }
    body {
      display: grid;
      place-items: center;
      background: radial-gradient(1200px 800px at 70% -20%, #1f2937 0%, var(--bg) 60%);
      color: var(--text);
      font: 16px/1.4 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, "Helvetica Neue", Arial, "Apple Color Emoji", "Segoe UI Emoji";
      padding: 1rem;
    }

    .card {
      width: 100%;
      max-width: 720px;
      background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.01));
      border: 1px solid var(--border);
      border-radius: 1.25rem;
      padding: 1.25rem;
      box-shadow: 0 10px 30px rgba(0,0,0,0.35);
      backdrop-filter: blur(8px);
    }

    .header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1rem;
      margin-bottom: 1rem;
    }

    .title {
      font-size: 1.25rem;
      font-weight: 700;
      letter-spacing: 0.4px;
    }

    .hint { color: var(--muted); font-size: 0.9rem; }

    .display {
      display: grid;
      place-items: center;
      padding: 1.25rem;
      border: 1px solid var(--border);
      border-radius: 1rem;
      background: #0b1220;
      margin-bottom: 1rem;
    }

    .time {
      font-variant-numeric: tabular-nums;
      font-size: clamp(2.2rem, 4.5vw + 1rem, 4rem);
      font-weight: 800;
      letter-spacing: 1px;
    }

    .controls {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 0.75rem;
      margin-bottom: 1rem;
    }

    button {
      appearance: none;
      border: 1px solid var(--border);
      background: #0b1220;
      color: var(--text);
      padding: 0.85rem 1rem;
      border-radius: 0.9rem;
      font-weight: 600;
      cursor: pointer;
      transition: transform 120ms ease, background 120ms ease, border-color 120ms ease;
    }
    button:hover { transform: translateY(-1px); border-color: #2a3a55; }
    button:active { transform: translateY(0); }
    button:disabled { opacity: 0.5; cursor: not-allowed; }

    .primary { border-color: rgba(34,197,94,0.35); box-shadow: inset 0 0 0 1px rgba(34,197,94,0.15); }
    .info { border-color: rgba(59,130,246,0.35); box-shadow: inset 0 0 0 1px rgba(59,130,246,0.15); }
    .danger { border-color: rgba(239,68,68,0.35); box-shadow: inset 0 0 0 1px rgba(239,68,68,0.15); }

    .laps {
      border: 1px solid var(--border);
      border-radius: 1rem;
      overflow: hidden;
      background: #0b1220;
    }

    .laps header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0.75rem 1rem;
      border-bottom: 1px solid var(--border);
      background: rgba(255,255,255,0.02);
    }

    .laps header h2 { margin: 0; font-size: 1rem; }

    .lap-list { max-height: 320px; overflow: auto; }

    table { width: 100%; border-collapse: collapse; font-variant-numeric: tabular-nums; }
    th, td { padding: 0.65rem 1rem; border-bottom: 1px solid var(--border); }
    th { text-align: left; color: var(--muted); font-weight: 600; position: sticky; top: 0; background: #0b1220; }

    .footer-note { color: var(--muted); margin-top: 0.75rem; font-size: 0.85rem; }
    kbd {
      background: #0b1220; border: 1px solid var(--border); border-bottom-color: #111827;
      padding: 0.1rem 0.35rem; border-radius: 0.4rem; font-weight: 700; font-size: 0.85rem;
    }