:root {
  --bg: #0b1120;
  --surface: #131d36;
  --text: #e6edff;
  --muted: #9eb0d6;
  --accent: #f97316;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top, #1e2b52 0%, var(--bg) 55%, #060913 100%);
  min-height: 100vh;
}
.container { max-width: 520px; margin: 0 auto; padding: 20px; }
.topbar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.topbar a { color: var(--accent); text-decoration: none; font-weight: 700; }
.topbar h1 { margin: 0; font-size: 1.9rem; }
.hud {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 10px;
  background: var(--surface);
  border: 1px solid #2c3d66;
  border-radius: 10px;
  padding: 10px;
  margin-bottom: 12px;
}
.hud p { margin: 0; color: var(--muted); }
button {
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 700;
}
#startBtn {
  background: var(--accent);
  color: #fff;
  padding: 8px 12px;
}
.pads {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}
.pad {
  aspect-ratio: 1 / 1;
  border-radius: 14px;
  opacity: 0.78;
  transition: transform 120ms ease, opacity 120ms ease;
}
.pad.active {
  transform: scale(1.03);
  opacity: 1;
  box-shadow: 0 0 20px rgba(255,255,255,0.35);
}
.pad-0 { background: #22c55e; }
.pad-1 { background: #ef4444; }
.pad-2 { background: #f59e0b; }
.pad-3 { background: #3b82f6; }
.status { margin-top: 10px; color: var(--muted); }
@media (max-width: 500px) {
  .hud { grid-template-columns: 1fr 1fr; }
  #startBtn { grid-column: span 2; }
}