sybox 
/* source: http://ah-sandbox.wikidot.com/component:collapsible-sidebar-x1 */
 
#top-bar .open-menu a {
        position: fixed;
        top: 0.5em;
        left: 0.5em;
        z-index: 5;
        font-family: 'Nanum Gothic', san-serif;
        font-size: 30px;
        font-weight: 700;
        width: 30px;
        height: 30px;
        line-height: 0.9em;
        text-align: center;
        border: 0.2em solid #888;
        background-color: #fff;
        border-radius: 3em;
        color: #888;
        pointer-events: auto;
}
 
@media not all and (max-width: 767px) {
 
    #top-bar .mobile-top-bar {
        display: block;
        pointer-events: none;
    }
 
    #top-bar .mobile-top-bar li {
        display: none;
    }
 
    #main-content {
        max-width: 708px;
        margin: 0 auto;
        padding: 0;
        transition: max-width 0.2s ease-in-out;
    }
 
    #side-bar {
        display: block;
        position: fixed;
        top: 0;
        left: -18rem;
        width: 15.25rem;
        height: 100%;
        margin: 0;
        overflow-x: hidden;
        overflow-y: auto;
        z-index: 10;
        padding: 1em 1em 0 1em;
        background-color: rgba(0,0,0,0.1);
        transition: left 0.4s ease-in-out;
 
        scrollbar-width: thin;
    }
 
    #side-bar:target {
        left: 0;
    }
    #side-bar:focus-within:where(:not(:target)) {
        left: 0;
    }
 
    #side-bar:target .close-menu {
        display: block;
        position: fixed;
        width: 100%;
        height: 100%;
        top: 0;
        left: 0;
        margin-left: 17rem;
        opacity: 0;
        z-index: -1;
        visibility: visible;
    }
    #side-bar:not(:target) .close-menu { display: none; }
 
    #top-bar .open-menu a:hover {
        text-decoration: none;
    }
sy