* { box-sizing: border-box; }
:root {
  color-scheme: dark;
  --bg: #061826;
  --panel: rgba(9, 31, 48, 0.88);
  --panel-border: rgba(164, 231, 255, 0.18);
  --ink: #ebfbff;
  --muted: #98c8d8;
  --accent: #ffd166;
  --accent-2: #7ce7ff;
  --good: #99f6b5;
}
body {
  margin: 0;
  font-family: "Avenir Next", "Trebuchet MS", sans-serif;
  background:
    radial-gradient(circle at top, #114b70 0%, rgba(17, 75, 112, 0.1) 34%),
    linear-gradient(180deg, #041018 0%, #072235 46%, #03131e 100%);
  color: var(--ink);
}
.wrap {
  max-width: 1040px;
  margin: 0 auto;
  padding: 18px;
}
.topnav {
  margin-bottom: 12px;
  color: var(--muted);
}
.topnav a {
  color: var(--accent);
  text-decoration: none;
}
.panel {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 22px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.24);
}
.hero {
  padding: 22px;
  margin-bottom: 16px;
}
.eyebrow {
  margin: 0 0 6px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  color: var(--accent-2);
}
.hero h1, .board-head h2, .stat-panel h2 {
  margin: 0;
}
.subtitle, .tip, .rules-list, .small-copy {
  color: var(--muted);
}
.hud {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  padding: 16px;
  margin-bottom: 16px;
}
.hud div {
  background: rgba(255,255,255,0.04);
  border-radius: 16px;
  padding: 12px;
}
.label {
  display: block;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 4px;
}
strong {
  font-size: 1.2rem;
}
.layout {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.85fr);
  gap: 16px;
}
.board-panel, .stat-panel {
  padding: 18px;
}
.board-head {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 16px;
  margin-bottom: 12px;
}
canvas {
  width: 100%;
  max-width: 100%;
  aspect-ratio: 360 / 520;
  display: block;
  border-radius: 20px;
  border: 1px solid rgba(185, 248, 255, 0.25);
  background: linear-gradient(180deg, #4cc9f0 0%, #1377a3 42%, #0d5478 100%);
  touch-action: none;
}
.side-panel {
  display: grid;
  gap: 16px;
}
.message {
  margin-top: 0;
  min-height: 3.8em;
  line-height: 1.45;
}
.rules-list {
  margin: 0;
  padding-left: 18px;
  display: grid;
  gap: 10px;
}
.controls {
  display: grid;
  gap: 10px;
}
button {
  appearance: none;
  border: none;
  border-radius: 14px;
  padding: 13px 16px;
  font: inherit;
  cursor: pointer;
  transition: transform 120ms ease, opacity 120ms ease, background 120ms ease;
}
button:active { transform: scale(0.98); }
button:disabled { cursor: not-allowed; opacity: 0.45; }
.action-btn {
  background: linear-gradient(180deg, #ffd166, #f4a261);
  color: #10202b;
  font-weight: 700;
}
.action-btn.secondary {
  background: linear-gradient(180deg, #90f1ff, #4cc9f0);
}
.action-btn.ghost, .ghost-btn {
  background: rgba(255, 255, 255, 0.06);
  color: var(--ink);
  border: 1px solid rgba(255,255,255,0.12);
}
.tip {
  margin-bottom: 0;
}
@media (max-width: 860px) {
  .hud { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .layout { grid-template-columns: 1fr; }
}
@media (max-width: 520px) {
  .wrap { padding: 12px; }
  .hero, .board-panel, .stat-panel { padding: 16px; }
  .hud { gap: 10px; }
}