:root,
[data-theme='light'] {
    /* Light Theme Colors */
    --bg-color: #fbfbfb;
    --text-color: #111111;
    --card-bg: #ffffff;
    --accent-color: #007bff;
    /* For buttons/links */
    --border-color: #ddd;
    --success-color: #28a745;
    /* For completed */
    --danger-color: #dc3545;
    /* For delete */
    --social-link: rgb(3, 112, 3);
    --social-link-hover:rgb(44, 177, 44);
    --hint-color: #555;
    /* Transition */
    --transition-speed: 0.3s ease;
    
}

[data-theme='dark'] {
    /* Dark Theme Colors */
    --bg-color: #121212;
    --text-color: #f1f1f1;
    --card-bg: #1e1e1e;
    --accent-color: #3399ff;
    /* For buttons/links */
    --border-color: #444;
    --success-color: #28d17c;
    /* For completed */
    --danger-color: #ff4d4f;
    /* For delete */
    --social-link: rgb(9, 144, 9);
    --social-link-hover:rgb(44, 177, 44);
    --hint-color: #888;
    /* Transition */
    --transition-speed: 0.3s ease;
}

header .theme-toggle-btn {
    margin: 15px auto;
    box-sizing: content-box;
    /* padding: 2px 20px; */
    width: 100px;
    /* border: 2px solid var(--border-color); */
    /* border-radius: 13px; */

    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-row: 1fr;
    align-items: stretch;
    justify-items: stretch;

    .theme-mode-btn {
        background: none;
        border: none;
        cursor: pointer;
        /* experiment */
        position: relative;
    }

    /* experiment */
    .theme-mode-btn.active::after {
        content: "";
        position: absolute;
        top: 32px;
        left: 50%;
        transform: translateX(-50%);
        width: 6px;
        height: 6px;
        background-color: var(--text-color);
        border-radius: 50%;
        margin-top: 4px;
    }

    #light-mode-btn {
        box-sizing: border-box;
        background-color: var(--card-bg);

        svg {
            fill: var(--text-color);
        }

        border-bottom:2px solid var(--border-color);
        border-radius: 13px 0 0 13px;
    }

    #night-mode-btn {
        background-color: var(--text-color);

        svg {
            fill: var(--card-bg);
        }

        border-radius: 0 13px 13px 0;
    }
}