* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    display: flex;
    justify-content: center;
    padding-top: 50px;
}

.container {
    width: 90%;
    max-width: 600px;
    background-color: white;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

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

#todoInput {
    flex: 1;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
}

#addTodo {
    padding: 10px 20px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

#addTodo:hover {
    background-color: #45a049;
}

.todo-list {
    list-style: none;
}

.todo-item {
    display: flex;
    align-items: center;
    padding: 10px;
    background-color: #f9f9f9;
    margin-bottom: 8px;
    border-radius: 5px;
    transition: background-color 0.3s;
}

.todo-item:hover {
    background-color: #f0f0f0;
}

.todo-text {
    flex: 1;
    margin-right: 10px;
}

.todo-item.completed .todo-text {
    text-decoration: line-through;
    color: #888;
}

.delete-btn {
    padding: 5px 10px;
    background-color: #ff4444;
    color: white;
    border: none;
    border-radius: 3px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.delete-btn:hover {
    background-color: #cc0000;
}

.checkbox {
    margin-right: 10px;
    width: 18px;
    height: 18px;
    cursor: pointer;
}