body {
    font-family: 'Poppins', sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    background: linear-gradient(60deg, #543ab7, #00acc1);
    color: white;
  }
  
  header {
    margin-top: 20px;
    text-align: center;
  }
  
  main {
    width: 100%;
    max-width: 800px;
    text-align: center;
    margin-top: 20px;
  }
  
  .controls {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
    margin-bottom: 20px;
  }
  
  #collageCanvas {
    border: 2px solid white;
    border-radius: 8px;
    display: block;
    margin: 0 auto;
  }