/* Center logo and inject tagline under it */
.wy-side-nav-search {
    text-align: center;
}

/* The link element under .wy-side-nav-search becomes empty if project='' */
.wy-side-nav-search > a {
    display: block;
    text-decoration: none;
}

/* Insert only tagline */
.wy-side-nav-search > a::after {
    content: "Machine Learning for Astronomical Discovery";
    display: block;
    font-size: 0.85em;
    margin-top: 0.3em;
    color: white; /* adjust color */
    font-style: italic; /* optional */
}