proxmox-backup/docs/custom.css

div.sphinxsidebar {
    height: calc(100% - 20px);
    overflow: auto;
}

h1.logo-name {
    font-size: 24px;
}

div.body img {
    width: 250px;
}
pre {
    padding: 5px 10px;
}

li a.current {
    font-weight: bold;
    border-bottom: 1px solid #000;
}
ul li.toctree-l1 {
    margin-top: 0.5em;
}
ul li.toctree-l1 > a {
    color: #000;
}

div.sphinxsidebar form.search {
    margin-bottom: 5px;
}

div.sphinxsidebar h3 {
    width: 100%;
}

div.sphinxsidebar h1.logo-name {
    display: none;
}
@media screen and (max-width: 875px) {
    div.sphinxsidebar p.logo {
        display: initial;
    }
    div.sphinxsidebar h1.logo-name {
        display: block;
    }
    div.sphinxsidebar span {
        color: #AAA;
    }
    ul li.toctree-l1 > a {
        color: #FFF;
    }
}