cssOMS/tree.scss

/* It's supposed to look like a tree diagram */
.tree, .tree ul, .tree li {
    list-style: none;
    padding: 0;
    position: relative;
}

.tree {
    display: table;
    text-align: center;

    .tree {
        border-top: 1px solid var(--bborder);
    }

    .box {
        margin: 0;
        padding: 1rem;
        border: 0;
    }

    ul {
        width: 100%;
        display: table;
    }

    ul:not(.tree) li:before {
        border: 1px solid var(--bborder);
    }

    li {
        display: table-cell;
        padding: .5em 0;
        vertical-align: top;

        &:before {
            content: "";
            left: 0;
            position: absolute;
            right: 0;
            top: 0;
        }

        &:first-child:before {
            left: 50%;
        }

        &:last-child:before {
            right: 50%;
        }

        > span {
            text-align: left;
            border: solid .1em var(--bborder);
            display: inline-block;
            margin: 0 .2em .5em;
            position: relative;
        }
    }

    ul:not(.tree):before, span:before {
        border: solid 1px var(--bborder);
        content: "";
        height: .45em;
        left: 50%;
        position: absolute;
    }

    ul:before {
        top: -.5rem;
    }

    span:before {
        top: -.5rem;
    }

    > li {
        &:before,
        &:after,
        > span:before {
            border: none;
        }
    }
}