.back-button{position:fixed;bottom:6vh;z-index:1000;width:7.5vw;height:6vh;-webkit-appearance:none;-moz-appearance:none;appearance:none;background:rgba(0,0,0,0);border:0;cursor:pointer;filter:drop-shadow(2px 2px 2px rgba(0,0,0,.8));display:none}@media(max-width:768px){.back-button{display:block}}.back-button img{width:24px;height:24px;filter:invert(1) opacity(.8);transition:filter .2s ease}.back-button:focus img,.back-button:hover img{filter:invert(1) opacity(1)}.back-button--about{filter:none}.back-button--about img{filter:invert(0) opacity(.8)}.back-button--about:focus img,.back-button--about:hover img{filter:invert(0) opacity(1)}