.back-top-fade-enter-active[data-v-57c0b96b],.back-top-fade-leave-active[data-v-57c0b96b]{transition:opacity .3s ease,transform .3s ease}.back-top-fade-enter-from[data-v-57c0b96b],.back-top-fade-leave-to[data-v-57c0b96b]{opacity:0;transform:translateY(12px)}