Good call. We (well, Josh mostly) recently did a lot of work to consolidate the bajillion LESS files used for all the Stack Exchange sites. Before that, this bottom border didn't exist on webapps.se, so it was configured to be white, i.e. invisible. This actually looks wrong in some places as you found, but even where it doesn't, the current "you are here" ...


The tooltip for the Impact widget is displaying under the bottom of the people reached label. So it is not overlap with the header. It has been status-completed. Screenshot for reference:

Only top voted, non community-wiki answers of a minimum length are eligible