body {
      font-family: Arial, sans-serif;
      background: #f4f4f9;
      margin: 0;
      padding: 20px;
      display: flex;
      justify-content: center;
    }
    .container {
      background: #fff;
      padding: 20px;
      border-radius: 12px;
      box-shadow: 0 4px 8px rgba(0,0,0,0.1);
      max-width: 500px;
      width: 100%;
    }
    h1 {
      text-align: center;
    }
    .input-group {
      display: flex;
      margin-bottom: 10px;
      gap: 5px;
    }
    .input-group input {
      flex: 1;
      padding: 8px;
      border: 1px solid #ccc;
      border-radius: 8px;
    }
    .input-group button {
      padding: 8px 12px;
      border: none;
      background: #007bff;
      color: #fff;
      border-radius: 8px;
      cursor: pointer;
    }
    .list-section {
      margin-bottom: 20px;
    }
    ul {
      list-style: none;
      padding: 0;
    }
    li {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 8px;
      border-bottom: 1px solid #eee;
    }
    li.completed span {
      text-decoration: line-through;
      color: #888;
    }
    li button {
      background: none;
      border: none;
      cursor: pointer;
      color: red;
    }
    .ai-section {
      text-align: center;
    }
    .ai-section button {
      padding: 8px 12px;
      border: none;
      background: #28a745;
      color: #fff;
      border-radius: 8px;
      cursor: pointer;
    }
    .ai-suggestions {
      margin-top: 10px;
      padding: 10px;
      background: #f0f0f0;
      border-radius: 8px;
      min-height: 40px;
    }