#share_bg_img { width: 100%; height: 100%; } #require_sign { position: fixed; bottom: 10px; right: 10px;width: 65px;height: 65px;} #introduce_guide { position: absolute; top: 0; right: 0; width: 71.875%; z-index: 200;} #overlay_pop { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background-color: rgba(0,0,0,0.7); z-index: 100; }