:root {
  --ink: #ecf2ec;
  --muted: rgba(236, 242, 236, 0.62);
  --line: rgba(255, 255, 255, 0.14);
  --glass: rgba(255, 255, 255, 0.045);
  --glow: rgba(125, 165, 148, 0.24);
  --bg: #08100b;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", sans-serif;
}

* { box-sizing: border-box; }

html {
  overscroll-behavior: none;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 8%, rgba(133, 158, 146, 0.18), transparent 28%),
    radial-gradient(circle at 82% 78%, rgba(80, 110, 100, 0.18), transparent 34%),
    var(--bg);
}

a { color: inherit; }

.game-shell {
  width: min(960px, calc(100% - 28px));
  margin: 0 auto;
  padding: 34px 0 54px;
}

.game-nav,
.game-panel,
.tile,
.cell,
canvas {
  border: 1px solid transparent;
  background:
    linear-gradient(145deg, rgba(255,255,255,.055), rgba(255,255,255,.025)) padding-box,
    linear-gradient(135deg, rgba(255,255,255,.42), rgba(255,255,255,.06), rgba(124,160,146,.2)) border-box;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.14), 0 0 36px var(--glow);
  backdrop-filter: blur(22px) saturate(160%);
  -webkit-backdrop-filter: blur(22px) saturate(160%);
}

.game-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 34px;
  padding: 14px 18px;
  border-radius: 999px;
}

.game-title {
  margin: 0 0 20px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(3.4rem, 12vw, 8rem);
  font-weight: 400;
  line-height: .9;
}

.game-panel {
  padding: clamp(18px, 4vw, 34px);
  border-radius: 28px;
}

.game-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 18px 0;
}

button {
  min-height: 42px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink);
  background: rgba(255,255,255,.045);
  cursor: pointer;
  transition: transform .28s cubic-bezier(.16,1,.3,1), border-color .28s;
}

button:hover { transform: translateY(-2px); border-color: rgba(255,255,255,.32); }
button:active { transform: scale(.98); }

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

.grid-2048 {
  display: grid;
  grid-template-columns: repeat(4, minmax(54px, 1fr));
  gap: clamp(8px, 2vw, 14px);
  max-width: 520px;
}

.tile {
  display: grid;
  place-items: center;
  aspect-ratio: 1;
  border-radius: 18px;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.5rem, 7vw, 3rem);
}

canvas {
  display: block;
  width: min(540px, 100%);
  aspect-ratio: 1;
  border-radius: 24px;
  touch-action: none;
}

.grid-2048 {
  touch-action: none;
}

@media (max-width: 560px) {
  .game-shell { width: calc(100% - 16px); padding-top: 18px; }
  .game-nav { border-radius: 18px; }
}