* { margin: 0; padding: 0; box-sizing: border-box; }
  body { background: #111; overflow: hidden; }
  canvas { display: block; }
  #info {
    position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%);
    color: #fff; font-family: sans-serif; font-size: 13px;
    background: rgba(0,0,0,0.5); padding: 8px 16px; border-radius: 20px;
    pointer-events: none;
  }
  #button-wrap {
    position: absolute;
    bottom: 60px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 10;
  }

  #firework-btn,
  #celebrate-btn,
  #message-btn {
    color: #fff;
    font-family: sans-serif;
    font-size: 16px;
    font-weight: bold;
    border: none;
    border-radius: 30px;
    padding: 13px 28px;
    cursor: pointer;
    letter-spacing: 1px;
  }

  #firework-btn {
    background: linear-gradient(135deg, #ff4dab, #ff8c00, #ffd700);
    box-shadow: 0 4px 20px rgba(255,100,150,0.5);
  }

  #celebrate-btn {
    background: linear-gradient(135deg, #7c4dff, #ff4dab, #ffd700);
    box-shadow: 0 4px 20px rgba(255,80,210,0.55);
  }

  #message-btn {
    background: linear-gradient(135deg, #00bcd4, #7c4dff, #ff4dab);
    box-shadow: 0 4px 20px rgba(70,180,255,0.5);
  }

  #message-modal {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.45);
    z-index: 30;
    font-family: sans-serif;
  }

  #message-modal.hidden {
    display: none;
  }

  #message-box {
    width: min(420px, calc(100vw - 32px));
    padding: 24px;
    border-radius: 26px;
    background: rgba(255, 248, 238, 0.98);
    box-shadow: 0 16px 50px rgba(0,0,0,0.35);
    text-align: center;
  }

  #message-box h2 {
    margin-bottom: 14px;
    color: #d63384;
    font-size: 22px;
  }

  #birthday-message {
    width: 100%;
    height: 110px;
    resize: none;
    border: 2px solid #ff9ecf;
    border-radius: 18px;
    padding: 14px;
    font-family: sans-serif;
    font-size: 16px;
    line-height: 1.45;
    outline: none;
  }

  #birthday-message:focus {
    border-color: #ff4dab;
    box-shadow: 0 0 0 4px rgba(255,77,171,0.15);
  }

  #message-actions {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 14px;
  }

  #message-actions button {
    border: none;
    border-radius: 18px;
    padding: 10px 18px;
    cursor: pointer;
    font-weight: bold;
  }

  #cancel-message-btn {
    background: #eee;
    color: #555;
  }

  #save-message-btn {
    background: linear-gradient(135deg, #ff4dab, #ff8c00);
    color: white;
  }

  #message-hint {
    margin-top: 10px;
    color: #777;
    font-size: 13px;
  }

  #celebrate-popup {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.75);
    padding: 34px 54px;
    border-radius: 34px;
    background: linear-gradient(135deg, rgba(255,77,171,0.95), rgba(255,140,0,0.95), rgba(255,215,0,0.95));
    color: white;
    font-family: sans-serif;
    font-size: clamp(44px, 7vw, 92px);
    font-weight: 900;
    text-align: center;
    text-shadow: 0 5px 18px rgba(120,0,80,0.45);
    box-shadow: 0 14px 60px rgba(255,130,0,0.55);
    opacity: 0;
    pointer-events: none;
    z-index: 20;
    white-space: nowrap;
  }

  #celebrate-popup.show {
    animation: popCelebrate 2.4s ease forwards;
  }

  @keyframes popCelebrate {
    0% { opacity: 0; transform: translate(-50%, -50%) scale(0.65) rotate(-5deg); }
    15% { opacity: 1; transform: translate(-50%, -50%) scale(1.08) rotate(2deg); }
    25% { transform: translate(-50%, -50%) scale(1) rotate(0deg); }
    80% { opacity: 1; transform: translate(-50%, -50%) scale(1) rotate(0deg); }
    100% { opacity: 0; transform: translate(-50%, -50%) scale(0.85) rotate(4deg); }
  }

  @media (max-width: 640px) {
    #button-wrap {
      flex-direction: column;
      bottom: 54px;
    }

    #firework-btn,
    #celebrate-btn {
      font-size: 14px;
      padding: 11px 22px;
    }

    #celebrate-popup {
      width: calc(100vw - 28px);
      white-space: normal;
      padding: 28px 22px;
    }
  }