* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #1a1a2e;
  font-family: 'Courier New', monospace;
  color: #eee;
}
#app { text-align: center; }
.ui-panel {
  background: #16213e;
  padding: 2rem;
  border-radius: 8px;
  border: 2px solid #0f3460;
}
.ui-panel h1, .ui-panel h2 { margin-top: 0; }
.difficulty { margin: 1rem 0; }
.difficulty label { margin-right: 1rem; }
button {
  background: #e94560;
  color: white;
  border: none;
  padding: 0.5rem 1.5rem;
  font-size: 1rem;
  cursor: pointer;
  border-radius: 4px;
}
button:hover { background: #ff6b6b; }
.game-panel { display: inline-block; }
.score { margin-bottom: 0.5rem; }
.grid {
  display: grid;
  gap: 1px;
  background: #0f3460;
  padding: 1px;
  border-radius: 4px;
  overflow: hidden;
}
.cell {
  width: 18px;
  height: 18px;
  background: #1a1a2e;
}
.cell.snake { background: #4ade80; }
.cell.food { background: #fbbf24; }