body {
      font-family: 'Segoe UI', sans-serif;
      background-color: #f9f9f9;
      padding: 40px;
      display: flex;
      justify-content: center;
    }

    .todo-container {
      width: 100%;
      max-width: 400px;
      background-color: #fff;
      padding: 25px;
      border-radius: 10px;
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    }

    h1 {
      text-align: center;
      color: #333;
      margin-bottom: 20px;
    }

    .input-section {
      display: flex;
      gap: 10px;
      margin-bottom: 20px;
    }

    .input-section input {
      flex: 1;
      padding: 10px;
      border: 1px solid #ccc;
      border-radius: 6px;
    }

    .input-section button {
      padding: 10px 15px;
      background-color: #007bff;
      color: white;
      border: none;
      border-radius: 6px;
      cursor: pointer;
    }

    .task-list {
      list-style: none;
      padding: 0;
    }

    .task-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f1f1f1;
      padding: 10px 12px;
      margin-bottom: 10px;
      border-radius: 6px;
    }

    .task-item.completed span {
      text-decoration: line-through;
      color: #777;
    }

    .task-item input[type="checkbox"] {
      margin-right: 10px;
    }

    .delete-btn {
      background: none;
      border: none;
      color: red;
      font-size: 18px;
      cursor: pointer;
    }