body {
      font-family: Arial, sans-serif;
      background: linear-gradient(135deg, #667eea, #764ba2);
      color: #fff;
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
      margin: 0;
    }

    .todo-container {
      background: #1e1e2f;
      padding: 20px;
      border-radius: 15px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.3);
      width: 350px;
    }

    h2 {
      text-align: center;
      margin-bottom: 20px;
    }

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

    input {
      flex: 1;
      padding: 10px;
      border: none;
      border-radius: 8px;
      outline: none;
    }

    button {
      padding: 10px 15px;
      border: none;
      border-radius: 8px;
      background: #667eea;
      color: white;
      cursor: pointer;
      transition: 0.3s;
    }

    button:hover {
      background: #5766c5;
    }

    ul {
      list-style: none;
      padding: 0;
      margin-top: 20px;
      max-height: 250px;
      overflow-y: auto;
    }

    li {
      background: #2c2c3e;
      padding: 10px;
      margin-bottom: 10px;
      border-radius: 8px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: 0.3s;
    }

    li.completed {
      text-decoration: line-through;
      opacity: 0.6;
    }

    .actions {
      display: flex;
      gap: 8px;
    }

    .actions button {
      padding: 5px 8px;
      font-size: 12px;
      border-radius: 6px;
    }

    .delete {
      background: #e74c3c;
    }

    .delete:hover {
      background: #c0392b;
    }

    .complete {
      background: #2ecc71;
    }

    .complete:hover {
      background: #27ae60;
    }