/* Standalone, shared back-to-top control: also works on the image album. */
.back-top53{position:fixed!important;right:22px;bottom:22px;z-index:9999;width:76px;height:76px;padding:8px;border:2px solid #d4faff;border-radius:50%;background:radial-gradient(circle at 32% 22%,#789aab,#173747 60%,#071a28);box-shadow:inset 0 2px 4px #ffffff80,inset 0 -4px 8px #0009,0 7px 22px #0008;cursor:pointer;opacity:0;visibility:hidden;transform:translateY(12px);transition:opacity .2s,transform .2s;touch-action:manipulation;display:block}
.back-top53.visible{opacity:1;visibility:visible;transform:none}
.back-top53:hover{background:radial-gradient(circle at 32% 22%,#9ab8c4,#244b5e 60%,#0c2535)}
.back-top53:focus-visible{outline:3px solid #ffd32c;outline-offset:4px}
.back-top60-arrow{display:block;width:100%;height:100%;filter:drop-shadow(0 4px 2px #0009);pointer-events:none}
.back-top53.visible .back-top60-arrow{animation:arrow60-pulse 1.8s ease-in-out infinite}
@keyframes arrow60-pulse{0%,100%{opacity:1;filter:drop-shadow(0 3px 2px #0008) drop-shadow(0 0 5px #ff3b3b88)}50%{opacity:.4;filter:drop-shadow(0 3px 2px #0008)}}
@container site69 (max-width:620px){.back-top53{right:14px;bottom:18px;width:66px;height:66px;padding:7px}}
@media(prefers-reduced-motion:reduce){.back-top53{transition:none}.back-top53.visible .back-top60-arrow{animation:none}}