.block-encadre>div{max-width:900px;margin:0 auto;border:3px solid #3dcb9a;border-radius:3px;padding:30px 40px;background-color:#fff;position:relative}.block-encadre>div:after{content:"";position:absolute;z-index:-1;top:15px;right:-15px;bottom:-15px;left:15px;background-color:#efb243;border-radius:3px}