#sticky-center-ads{ position:fixed; top:50%; left:50%; transform:translate(-50%,-50%); background:#fff; padding:15px; box-shadow:0 5px 25px rgba(0,0,0,.2); z-index:9999; max-width:600px; width:90%; text-align:center; display:none; } #close-sticky{ position:absolute; top:-10px; right:-10px; background:#000; color:#fff; border:none; border-radius:50%; width:30px; height:30px; cursor:pointer; } .sticky-item{ margin:10px 0; } #sticky-center-ads:before{ content:""; position:fixed; top:0; left:0; width:100%; height:100%; background:rgba(0,0,0,0.4); z-index:-1; }