*{padding:0;margin:0;font-family:Helvetica,Arial,sans-serif;box-sizing: border-box;}
ul{list-style-type:none}
html,body,#wrapper,#content,#menu{height:100%;overflow:hidden}
#wrapper{margin:10px;display:flex;gap:20px}
#menu{width:20em}
#content{flex:1;background:#555}
#menu ul{overflow-y:auto;padding-bottom:200px;padding-right:20px;height:100%}
#menu li{display:flex;align-items:center;gap:20px;cursor:pointer;justify-content:space-between;padding:10px 0;border-bottom:5px solid #ccc;white-space:nowrap}
#content>div {overflow-y:auto;padding:10px 10px 200px 10px;max-height:100%;margin:0 auto}
#content>div div{background:#000;cursor:pointer;box-shadow:5px 5px 5px 1px rgba(0,0,0,0.1);width:170px;height:170px;justify-content:center;display:flex;align-items:center;padding:5px;float:left;margin:1px}
#content img:hover{filter: saturate(0);}
#bg{position:fixed;top:0;right:0;left:0;bottom:0;background:rgba(0,0,0,0.85);display:none;text-align:center;padding:30px}
#imgc{flex:1}
#bg img{max-width:100%;max-height:100%}
#bg .nav{font-size:60px;color:#fff;cursor:pointer}
#bg.waiting{cursor:wait}