/* ── Z-index tokens ────────────────────────────────────────────
   A small stacking scale for the few elements that sit above normal
   page flow - the sticky site header and the back-to-top control.
   Add here rather than hardcoding a number on the component itself.
*/
:root {
    --z-sticky-header: 100;
    --z-back-to-top: 90;
}