I switched the colors, also made the gray a little lighter (making it the side-bar hover color).
In order to not cause more confusion, we could at the same time slightly decrease the font size of the latter?
Font sizes throughout the whole page are pretty consistent and making the font smaller disturbs the view a little. Lighter gray also makes the suggestions a bit less prominent, so maybe that could be enough.
I will also try to think about other ways to deal with the look of suggestions.