#vx-backtop{position:fixed;right:14px;bottom:80px;width:54px;height:54px;border-radius:50%;
background: radial-gradient(ellipse at center, #ffd84a 0%, #ffb300 65%, #e89b00 100%);
box-shadow: 0 6px 16px rgba(0,0,0,.2); display:flex; align-items:center; justify-content:center;
cursor:pointer; z-index:1039; opacity:0; transform:translateY(12px) scale(.9); transition:opacity .18s, transform .18s; overflow:hidden}
#vx-backtop.show{opacity:1; transform:translateY(0) scale(1);}
#vx-backtop .arrow{position:absolute; width:0; height:0; border-left:9px solid transparent; border-right:9px solid transparent; border-bottom:14px solid #222;}
#vx-backtop .arrow{ animation: vx-bob 1.2s ease-in-out infinite; }
@keyframes vx-bob{ 0%{ transform: translateY(4px);} 50%{ transform: translateY(-2px);} 100%{ transform: translateY(4px);} }
#vx-backtop canvas{position:absolute; inset:0; pointer-events:none; mix-blend-mode:screen; opacity:.85}
@media (prefers-reduced-motion: reduce){
  #vx-backtop .arrow{ animation: none; }
}