.pre_img.is-loading{position:relative;min-height:400px}.pre_img.is-loading::after{content:"";position:absolute;top:50%;left:50%;width:60px;height:60px;transform:translate(-50%,-50%);background:url(../images/loader.gif) center center no-repeat;background-size:contain;z-index:100}.pre_img.is-loading #gimg{opacity:.3;transition:opacity .2s}