.line-numbers {
    position: relative;
    padding-left: 3.8em; /* works for line-numbers below 1000 lines */
}

.line-numbers .line-numbers-rows {
    position: absolute;
    pointer-events: none;
    top: 0;
    left: 0;
    width: 3em;
    letter-spacing: -1px;
    border-right: 1px solid #999;
    counter-reset: linenumber;
    min-height: 100%;
}

.line-numbers-rows > .line-number {
    pointer-events: none;
    display: block;
    counter-increment: linenumber;
}

.line-numbers-rows > .line-number::before {
    content: counter(linenumber);
    color: #999;
    display: block;
    padding-right: 0.8em;
    text-align: right;
}