.wy-menu-vertical ul > li.toctree-l5 > a {
    display: block;
    background: #adadad;
    padding: .4045em 7.326em;
}

.wy-menu-vertical ul > li.toctree-l5 > a:hover {
    background: #afafaf;
}

.wy-menu-vertical li.toctree-l4 > ul {
    display: none;
}

.wy-menu-vertical li.toctree-l4.current > ul {
    display: block;
}