[dir] body{background:url(https://i.pinimg.com/originals/65/9c/6f/659c6f3a1f1614d833ba197ff7032151.jpg)}body,html{font-family:sans-serif;height:100%}[dir] body,html[dir]{margin:0}header{height:70px}#app{align-items:center;display:flex;flex-direction:column;justify-content:center;height:calc(100% - 140px)}[dir] #app{text-align:center}#content{align-content:center;width:400px}[dir] #content{margin:auto}footer{height:70px}