pre.pure-highlightjs {
    background-color: transparent!important;
    border: none;
    padding: 0;
    background: linear-gradient(to right , black 0%, black 50%, white 50%, white 100% );
}
pre.pure-highlightjs ::selection {
    background:maroon!important;
    color:#fff!important;
}

pre.pure-highlightjs ::-moz-selection {
    background:maroon!important;
    color:#fff!important;
}

pre.pure-highlightjs ::-webkit-selection {
    background:maroon!important;
    color:#fff!important;
}