Messy screen

It looks like either your browser zoom isn't the default, the window isn't maximized, your resolution isn't very high, or you have made your board a lot smaller (https://support.chess.com/article/632-how-do-i-change-my-board-size) causing things to overlap.
The site isn't going to be able to get everything looking great on all possible configurations and resizing can cause layout issues but should be usable with overlap like you're seeing.
This is a screenshot of a game I was playing. It's quite a mess, the spacing is off. Shouldn't be that big a fix I would have thought.