:root {
  --bg: #0b1220;
  --bg2: #101d35;
  --panel: #121f3a;
  --line: rgba(148, 163, 184, 0.25);
  --text: #e2e8f0;
  --muted: #9ca3af;
}

* { box-sizing: border-box; }

html,
body {
  margin: 0;
  min-height: 100%;
  font-family: "Segoe UI", "Tahoma", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 20% 10%, #1d4ed8, transparent 30%),
    radial-gradient(circle at 80% 15%, #0f766e, transparent 28%),
    linear-gradient(180deg, var(--bg2), var(--bg));
}

.shell {
  width: min(980px, 100%);
  margin: 0 auto;
  padding: 12px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 10px;
}

.topbar h1 { margin: 0; font-size: 1.35rem; }
.topbar p { margin: 4px 0 0; color: var(--muted); font-size: 0.9rem; }

#restartBtn {
  border: 0;
  border-radius: 10px;
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: #fff;
  font-weight: 700;
  padding: 9px 14px;
  cursor: pointer;
}

.hud {
  margin: 12px 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}

.chip {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 10px;
  display: flex;
  justify-content: space-between;
  background: linear-gradient(180deg, var(--panel), #18284b);
}

.chip span { color: var(--muted); }

#game {
  width: 100%;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: 12px;
  display: block;
  background: #0c1730;
}

.tip {
  margin: 9px 0 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 760px) {
  .hud {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}