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

body {
    font-family: Arial, sans-serif;
    background: #f4f6f8;
    min-height: 100vh;

    display: flex;
    justify-content: center;
    align-items: center;

    padding: 20px;
}

.todo-container {
    background: white;
    width: 100%;
    max-width: 550px;

    padding: 35px;
    border-radius: 16px;

    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
}

h1 {
    font-size: 32px;
    color: #222;
    margin-bottom: 8px;
}

.subtitle {
    color: #777;
    margin-bottom: 25px;
}

/* Input area */

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

#taskInput {
    flex: 1;

    padding: 13px 15px;

    border: 1px solid #ddd;
    border-radius: 8px;

    font-size: 16px;
    outline: none;
}

#taskInput:focus {
    border-color: #555;
}

#addBtn {
    padding: 0 20px;

    border: none;
    border-radius: 8px;

    background: #222;
    color: white;

    font-size: 16px;
    cursor: pointer;
}

#addBtn:hover {
    background: #444;
}

/* Task information */

.task-info {
    display: flex;
    justify-content: space-between;
    align-items: center;

    margin: 25px 0 15px;

    color: #777;
    font-size: 14px;
}

#clearBtn {
    border: none;
    background: none;

    color: #555;
    cursor: pointer;
}

#clearBtn:hover {
    text-decoration: underline;
}

/* Task list */

#taskList {
    list-style: none;
}

.task {
    display: flex;
    align-items: center;
    gap: 12px;

    padding: 14px 0;

    border-bottom: 1px solid #eee;
}

.task-checkbox {
    width: 19px;
    height: 19px;

    cursor: pointer;
}

.task-text {
    flex: 1;
    font-size: 16px;
    color: #333;

    word-break: break-word;
}

.task.completed .task-text {
    text-decoration: line-through;
    color: #999;
}

.delete-btn {
    border: none;
    background: none;

    color: #999;
    font-size: 18px;

    cursor: pointer;
}

.delete-btn:hover {
    color: #e63946;
}

/* Empty message */

#emptyMessage {
    text-align: center;
    color: #aaa;

    padding: 30px 0;
}

/* Mobile */

@media (max-width: 500px) {

    .todo-container {
        padding: 25px 20px;
    }

    h1 {
        font-size: 28px;
    }

    .input-section {
        flex-direction: column;
    }

    #addBtn {
        padding: 12px;
    }
}