ul.domtree, ul.domtree ul {
    margin: 0;
    padding: 0 0 0 2em;
}
 
ul.domtree li {
    list-style: none;
    position: relative;
}
 
ul.domtree li:before {
    position: absolute;
    content: '';
    top: -0.1em;
    left: -0.5em;
    width: 0.4em;
    height: 0.615em;
    border-style: none none solid solid;
    border-width: 0.05em;
}
 
/*
ul.domtree li:last-child {
    color: gray;
}
ul.domtree li:not(:last-child) {
    color: red;
}
*/
 
ul.domtree li:not(:last-child):after {
    position: absolute;
    content: '';
    top: 0;
    left: -0.5em;
    bottom: 0;
    border-style: none none none solid;
    border-width: 0.05em;
}