body {
      margin: 0;
      padding: 0;
      font-family: 'Prompt', sans-serif;
      background: linear-gradient(135deg, #fdfbfb, #ebedee);
      color: #333;
      text-align: center;
    }

    .container {
      max-width: 400px;
      width: 90%;
      margin: 60px auto;
      padding: 20px;
      background-color: #ffffffcc;
      border-radius: 16px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    }

    h1 {
      font-size: 24px;
      margin-bottom: 20px;
    }

    .wallet-box {
      background-color: #A8E6CF;
      color: white;
      padding: 16px;
      border-radius: 12px;
      font-size: 20px;
      font-weight: bold;
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    }

    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 20px;
      justify-content: center;
    }

    .action-btn {
      flex: 1 1 45%;
      padding: 10px;
      font-size: 16px;
      background-color: #FF8C94;
      color: white;
      border: none;
      border-radius: 8px;
      cursor: pointer;
      transition: background-color 0.2s ease;
    }

    .action-btn:hover {
      background-color: #e67c85;
    }

    .loading {
      font-size: 14px;
      color: #666;
      margin-top: 10px;
    }

    .history {
      margin-top: 30px;
      text-align: left;
    }

    .history h2 {
      font-size: 18px;
      margin-bottom: 10px;
    }

    .history-item {
      padding: 8px 12px;
      border-radius: 8px;
      margin-bottom: 6px;
      font-size: 15px;
    }

    .in {
      background-color: #d4f8d4;
      color: #2e7d32;
    }

    .out {
      background-color: #fddede;
      color: #c62828;
    }

    @media (max-width: 480px) {
      h1 { font-size: 20px; }
      .wallet-box { font-size: 18px; padding: 14px; }
      .action-btn { font-size: 15px; padding: 10px; }
    }