:root {
  --bg: #07120c;
  --panel: #0d1f16;
  --line: #1d3a2a;
  --text: #d8f3e3;
  --dim: #7fa892;
  --accent: #4ade80;
  --danger: #f87171;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background:
    radial-gradient(120% 80% at 50% 0%, #0f2419 0%, var(--bg) 60%, #030906 100%);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", "Microsoft YaHei", sans-serif;
  -webkit-tap-highlight-color: transparent;
}

.wrap {
  min-height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 18px 14px 26px;
}

.hud {
  width: min(92vw, 560px);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 8px 10px;
  background: linear-gradient(180deg, #12291d 0%, #0b1a12 100%);
  border: 1px solid var(--line);
  border-radius: 12px;
}

.stat .label {
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--dim);
}

.stat strong {
  font-size: 22px;
  font-variant-numeric: tabular-nums;
  color: var(--accent);
}

.board {
  position: relative;
  width: min(92vw, 560px);
  aspect-ratio: 1 / 1;
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow:
    0 24px 60px rgba(0, 0, 0, .55),
    inset 0 0 0 1px rgba(255, 255, 255, .03);
}

canvas#game {
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
}

.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 24px;
  text-align: center;
  background: rgba(4, 12, 8, .72);
  backdrop-filter: blur(3px);
  transition: opacity .18s ease;
}

.overlay[hidden] {
  display: none;
}

/* 音效开关：放在棋盘右上角，压在弹层之上，随时能关 */
.mute {
  position: absolute;
  top: 10px;
  right: 10px;
  z-index: 3;
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  padding: 0;
  font-size: 16px;
  line-height: 1;
  color: var(--text);
  background: rgba(6, 20, 13, .55);
  border: 1px solid rgba(120, 200, 160, .28);
  border-radius: 10px;
  cursor: pointer;
  backdrop-filter: blur(4px);
  transition: background .15s ease, transform .12s ease;
}

.mute:hover { background: rgba(14, 40, 26, .78); }
.mute:active { transform: scale(.94); }

.overlay h1 {
  margin: 0;
  font-size: clamp(26px, 7vw, 40px);
  letter-spacing: .06em;
}

.overlay p {
  margin: 0;
  max-width: 34ch;
  color: var(--dim);
  font-size: 14px;
  line-height: 1.6;
}

.overlay button {
  margin-top: 8px;
  padding: 11px 26px;
  font: inherit;
  font-size: 15px;
  color: #04120a;
  background: var(--accent);
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  transition: transform .12s ease, filter .12s ease;
}

.overlay button:hover { filter: brightness(1.08); }
.overlay button:active { transform: scale(.97); }

.overlay.dead h1 { color: var(--danger); }

.hint {
  margin: 0;
  max-width: 46ch;
  color: var(--dim);
  font-size: 12px;
  line-height: 1.6;
  text-align: center;
}

.pad {
  display: grid;
  grid-template-columns: repeat(3, 52px);
  grid-template-rows: repeat(2, 52px);
  gap: 8px;
  justify-content: center;
}

.pad-btn {
  font: inherit;
  font-size: 16px;
  color: var(--text);
  background: #10241a;
  border: 1px solid var(--line);
  border-radius: 12px;
  cursor: pointer;
  user-select: none;
  touch-action: manipulation;
}

.pad-btn:active { background: #17341f; }

.pad-btn.up    { grid-column: 2; grid-row: 1; }
.pad-btn.left  { grid-column: 1; grid-row: 2; }
.pad-btn.down  { grid-column: 2; grid-row: 2; }
.pad-btn.right { grid-column: 3; grid-row: 2; }

@media (hover: hover) and (pointer: fine) {
  .pad { display: none; }
}