:root{--back-to-top-right:max(24px,calc((100vw - var(--page-content-width))/2 - 48px));--back-to-top-bottom:120px;--back-to-top-size:48px}.back-to-top{right:var(--back-to-top-right);bottom:var(--back-to-top-bottom);z-index:45;width:var(--back-to-top-size);height:var(--back-to-top-size);border:1px solid var(--border,#dce7f5);background:var(--surface,#fff);color:var(--accent,#245ea5);cursor:pointer;border-radius:14px;place-items:center;transition:background .18s,box-shadow .18s,transform .18s;display:grid;position:fixed;box-shadow:0 5px 22px #193f681a}.back-to-top:hover{background:var(--surface,#edf5ff);transform:translateY(-2px);box-shadow:0 8px 24px #193f6826}.back-to-top:focus-visible{outline-offset:4px;outline:3px solid #ffb52b}@media (width<=540px){:root{--back-to-top-right:16px;--back-to-top-bottom:calc(max(18px,env(safe-area-inset-bottom)) + 128px)}}@media (prefers-reduced-motion:reduce){.back-to-top{transition:none}.back-to-top:hover{transform:none}}@media (width<=767px){.back-to-top-home{bottom:calc(max(18px,env(safe-area-inset-bottom)) + 104px)}}