.square{position:absolute;width:100px;height:100px;background:#ccc;border:5px solid #000;z-index:0}.pre{margin-top:200px}ul{margin:0;padding:0}li{-webkit-box-sizing:border-box;box-sizing:border-box;height:30px;margin:5px 0;padding:5px;color:#fff;list-style-type:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}.placeholder{background:transparent;border:2px dashed #666;-webkit-transition:height 1s,opacity 1s,margin 1s,padding 1s,border 1s;transition:height 1s,opacity 1s,margin 1s,padding 1s,border 1s;opacity:1}.hide{opacity:0;margin:0;padding:0;height:0;border:0}.drag{-webkit-box-shadow:0 0 10px rgba(0,0,0,.3);box-shadow:0 0 10px rgba(0,0,0,.3);z-index:2}#app{margin:10px}#app *{font-family:Verdana,Geneva,Tahoma,sans-serif}#app span{background:#697;margin:5px 5px 5px 0;padding:5px;cursor:pointer;color:#fff}#app span.active{background:#146830}#app span:hover{background:#7a8}#app .page{margin-top:30px}