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

body {
    font-family: Arial, sans-serif;
    background: #f5f5f7;
    color: #1f1f1f;
    min-height: 100vh;
}

.app {
    width: 90%;
    max-width: 700px;
    margin: 0 auto;
    padding: 70px 0;
}

.header {
    margin-bottom: 30px;
}

.eyebrow {
    font-size: 12px;
    font-weight: bold;
    letter-spacing: 2px;
    color: #666;
    margin-bottom: 8px;
}

h1 {
    font-size: 42px;
    margin-bottom: 8px;
}

.subtitle {
    color: #777;
    font-size: 16px;
}

.todo-card {
    background: white;
    border-radius: 18px;
    padding: 24px;
    box-shadow: 0 10px 35px rgba(0, 0, 0, 0.06);
}

.input-area {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

#todo-input {
    flex: 1;
    padding: 15px;
    border: 1px solid #ddd;
    border-radius: 10px;
    font-size: 15px;
    outline: none;
}

#todo-input:focus {
    border-color: #333;
}

.input-area button {
    border: none;
    background: #222;
    color: white;
    padding: 0 20px;
    border-radius: 10px;
    cursor: pointer;
    font-weight: bold;
}

.filters {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.filter {
    border: none;
    background: #f1f1f1;
    padding: 9px 14px;
    border-radius: 8px;
    cursor: pointer;
}

.filter.active {
    background: #222;
    color: white;
}

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

.todo-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 0;
    border-bottom: 1px solid #eee;
}

.todo-item:last-child {
    border-bottom: none;
}

.todo-checkbox {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.todo-text {
    flex: 1;
    font-size: 15px;
}

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

.delete-btn {
    border: none;
    background: transparent;
    color: #999;
    cursor: pointer;
    font-size: 14px;
}

.delete-btn:hover {
    color: #e53935;
}

.bottom-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 20px;
    padding-top: 15px;
    border-top: 1px solid #eee;
    color: #777;
    font-size: 14px;
}

#clear-completed {
    border: none;
    background: transparent;
    color: #555;
    cursor: pointer;
}

#clear-completed:hover {
    color: #000;
}

.empty {
    text-align: center;
    padding: 30px 0;
    color: #999;
}

@media (max-width: 600px) {

    .app {
        padding: 40px 0;
    }

    h1 {
        font-size: 32px;
    }

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

    .input-area button {
        padding: 14px;
    }

    .todo-card {
        padding: 18px;
    }

    .filters {
        overflow-x: auto;
    }
}