::marker{font-size:0}details{padding-left:20px}summary:before{content:"";display:inline-block;width:24px;height:24px;background:url(/folder.svg);background-size:100%;vertical-align:-2px;margin-right:6px;margin-left:-20px}[open]>summary:before{background:url(/folder-open.svg);background-size:100%}