/* Gravity Puzzle */
body { background: #8e44ad; }
.container { max-width: 600px; margin: 40px auto; color: #fff; text-align: center; }
h1 { margin: 20px 0; }
.canvas-container {
  border: 4px solid #2c3e50;
  border-radius: 10px;
  background: #ecf0f1;
  width: 500px;
  height: 400px;
  margin: 20px auto;
  overflow: hidden;
}
.controls { text-align: center; margin: 20px 0; }
.btn {
  padding: 10px 22px; font-size: 16px; cursor: pointer;
  background: #3498db; color: #fff; border: none; border-radius: 5px;
}
.btn:hover { background: #2980b9; }