html,body{height:100%;box-sizing:border-box;margin:0}*,*::before,*::after{box-sizing:inherit}body{display:flex;flex-direction:column;height:100vh;max-width:800px;margin-left:auto;margin-right:auto}.wrapper{flex:1 0 auto;padding:1em}footer{flex-shrink:0;padding:1em}