.back-to-top{right:var(--space-4);border-radius:var(--radius-circle);background:var(--color-neutral-900);width:3.5rem;height:3.5rem;color:var(--color-text-invert);font-size:var(--font-size-md);cursor:pointer;box-shadow:var(--shadow-md);z-index:var(--z-toast);opacity:0;visibility:hidden;transform:translateY(var(--space-2));border:0;justify-content:center;align-items:center;transition:opacity .25s,transform .25s,visibility .25s;display:inline-flex;position:fixed}.back-to-top.is-visible{opacity:1;visibility:visible;transform:translateY(0)}.back-to-top:hover{background:var(--color-neutral-800)}