blurry thumbnails on category page

So my website looks pretty good except for a few minor problems.

On my nav bar I have three categories as clickable, and when you click it’s a preview page with thumbnails of my galleries. Some of the thumbnails are blurry and some are clear. I don’t know how to make the thumbnails not blurry. Any advice?

Also, on my “home” and “contact” pages, which are actual pages listed under my menu>pages, there is a pink bar across the top that says the name of the page. i either want this on every menu item (categories and pages), or not at all. I know this is vague, but any suggestions?

my site is http://www.annaleerigdon.com

Thanks