.box{--b:4;display:inline-block;padding:5px 0px 5px 0px;margin:0px;margin-right:calc(var(--b)*40px);border:2px solid;border-right:0;position:relative;width:250px;text-align:center}.box:before,.box:after{content:"";position:absolute;margin-left:-1px;top:-1px;left:100%;bottom:50%;width:calc(var(--b)*20px);background:linear-gradient(to right,#000 28%,transparent 29%) 1px 0/calc(100%/var(--b)) 100%;transform:skewX(45deg);transform-origin:top}.box:after{transform:skewX(-45deg);transform-origin:bottom;bottom:-1px;top:50%}