header{transition:top 0.3s ease,padding-left 0.3s ease}div#main{transition:margin-left 0.3s ease}nav{transition:left 0.3s ease,margin-top 0.3s ease,opacity 0.3s ease}.mask{transition:visibility 0s,opacity 0.3s ease}.tab-tabs>li::after{transition:transform 250ms ease 0s}