a.underline
{
    font-family: var(--mono);
    font-size: calc(var(--smallFontSize) / 2);
    color: var(--black);
    text-decoration: none;
    display: inline-block;
    position: relative;
    padding-left: 0.5rem;
    border-left: 2px solid var(--pistachio);
}

a.underline::before
{
    content: '';
    position: absolute;
    width: 100%;
    transform: scaleX(0);
    height: 100%;
    bottom: 0;
    left: 0;
    transform-origin: bottom right;
    transition: transform 0.5s ease-out;
    background-color: var(--pistachio);
}

a.underline:hover::before
{
    transform: scaleX(1);
    transform-origin: bottom left;
}