python-gallery/gallery/user/themes/default/ui/nav.scss

nav {
    margin: 0;
    padding: 0;

    max-width: 100vw;
    width: 3.5rem;
    height: 100dvh;

    display: flex;
    flex-direction: column;
    justify-content: space-between;

    position: fixed;
    top: 0;
    left: 0;

    background-color: $black300;
    color: $white100;

    box-sizing: border-box;
    z-index: 69;
    transition: width 0.4s cubic-bezier(.76,0,.17,1), background-color 0.3s ease-in-out;

    div {
        display: flex;
        flex-direction: column;
        //gap: 0.25rem;

        a {
            margin: 0;
            padding: 1rem;

            width: 3.5rem;
            height: 3.5rem;

            display: flex;
            flex-direction: row;
            align-items: center;
            //gap: 0.5rem;

            position: relative;

            text-decoration: none;
            color: $white100;

            box-sizing: border-box;

            i, svg {
                margin: 0;
                font-size: 1.5rem;
                color: $white100;
                transition: color 0.2s ease-out;
            }

            span {
                margin: 0;
                padding: 0.5rem 0.75rem;

                display: block;

                position: absolute;
                top: 50%;
                left: 3rem;
                transform: translateY(-50%);

                font-family: $font-body;
                font-size: 1rem;
                font-weight: 600;

                background-color: $black300;
                color: $white100;
                opacity: 0;
                border-radius: $rad;

                transition: opacity 0.2s cubic-bezier(.76,0,.17,1), left 0.2s cubic-bezier(.76,0,.17,1);

                pointer-events: none;
            }

            &:hover {
                //background-color: $black200;

                i, svg {
                    color: $green;
                }

                span {
                    opacity: 1;
                    left: 3.8rem;
                    transform: translateY(-50%);
                }
            }
        }
    }
}