ul.tree,
ul.tree ul {
    list-style: none;
    margin: 0;
    padding: 0;
    font-family: 'Roboto Mono', monospace;
}

ul.tree ul {
    margin-left: 10px;
}

ul.tree li {
    margin: 0;
    padding: 0 7px;
    line-height: 20px;
    border-left: 2px solid rgb(100, 100, 100);

}

ul.tree li:last-child {
    border-left: none;
}

ul.tree li:before {
    position: relative;
    top: -0.3em;
    height: 1em;
    width: 12px;
    color: white;
    border-bottom: 1px solid rgb(100, 100, 100);
    content: "";
    display: inline-block;
    left: -7px;
}

ul.tree li:last-child:before {
    border-left: 2px solid rgb(100, 100, 100);
}