:where(*) { box-sizing: border-box; } :where(body) { margin: 0; }:where(*){box-sizing:border-box;}:where(body){margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;}:where(*){box-sizing:border-box;}:where(body){margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;}:where(*){box-sizing:border-box;}:where(body){margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;}