Currently, when following an anchor link (e.g. `/pagename#section` to jump to a specific section on a specific page), the page scrolls up to much and the start of the content in `section` is overlayed by the fixed menu. We should fix this. Here are a few links that might be helpful: * https://stackoverflow.com/questions/10732690/offsetting-an-html-anchor-to-adjust-for-fixed-header * https://gomakethings.com/how-to-prevent-anchor-links-from-scrolling-behind-a-sticky-header-with-one-line-of-css/ * https://css-tricks.com/fixed-headers-and-jump-links-the-solution-is-scroll-margin-top/