xonsh/docs/_static/custom.css

th > p:first-child,
td > p:first-child,
li > p:first-child,
dt > p:first-child,
dd > p:first-child {
    margin-top: 0px;
}

th > p:last-child,
td > p:last-child, 
li > p:last-child,
dt > p:last-child,
dd > p:last-child {
    margin-bottom: 0px;
}

li > p:first-child {
    margin-top: 0px;
}
li > p:last-child {
    margin-bottom: 0px;
}