Fix spacing in TOC; Change pre blocks to scroll w/ scroll shadows The lists in a TOC have too much spacing after adding the lobotomized owl. Shrink it for desktop. The pre example code was getting wrapped and it was confusing. Some single lines looked like two etc. So change pre's to overflow with a scroll bar. To make the scroll section obvious (since scrollbars won't always be shown on mobile), add scroll shadows in direction of scrollability. I made arc shaped shadows rather than straight shadows as they look better.

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