.main{background-image:linear-gradient(0deg,transparent calc(100% - 1px),#f0f0f0 calc(100% - 1px)),linear-gradient(90deg,transparent calc(100% - 1px),#f0f0f0 calc(100% - 1px));background-size:8px 8px;background-repeat:repeat;background-position:center center;background-color:#fff}