.back-to-top{position:fixed;right:max(20px,env(safe-area-inset-right));bottom:calc(max(20px,env(safe-area-inset-bottom)) + var(--back-to-top-lift,0px));z-index:19;display:grid;place-items:center;width:48px;height:48px;padding:0;border:1px solid rgba(255,255,255,.3);border-radius:50%;background:#172839;color:#fff;box-shadow:0 4px 18px rgba(0,0,0,.2);cursor:pointer;touch-action:manipulation}
.back-to-top[hidden]{display:none}.back-to-top svg{width:23px;height:23px;pointer-events:none}.back-to-top:hover{background:#2e4c63}.back-to-top:focus-visible{outline:3px solid #4187bb;outline-offset:4px}body:has(dialog[open]) .back-to-top{visibility:hidden;pointer-events:none}
@media(max-width:700px){.back-to-top{right:max(14px,env(safe-area-inset-right));width:46px;height:46px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}