Chrome paints an empty scrollbar gutter white and takes the page scrollbar's style from body, not html. It now always shows the page scrollbar (an empty track where nothing scrolls), styled via body::-webkit-scrollbar with the header and page colours; the header's translucent bottom line is a layer of its own. Firefox keeps the gutter. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>