.block_title{position:relative;z-index:9}.block_title::after{content:" ";display:block;width:100%;height:100%;position:absolute;border:3px solid #fff;background:0 0;z-index:10;top:10px;left:10px}.block_title::before{content:" ";display:block;width:100%;height:100%;position:absolute;border:3px solid #fff;background:0 0;z-index:10;bottom:10px;right:10px}