Thanks again for your question, Christina. We spoke about this over the phone, but I thought I’d answer here as well in case anyone is running into the same issue.

There’s not a concrete answer to what size your background image should be, but you’re looking for a balance between size in KB/MB (so your page doesn’t load too slowly) and size in pixels (so your image looks sharp across browsers).

In Christina’s case, I recommended the small or higher and also recommended that she try to compress the image a bit in Photoshop to keep the same pixels, but bring down the file size a bit.

If anyone’s interested in a really in-depth look (that includes comparisons of common screen sizes for desktop and mobile), there’s a great article here: http://www.webmalama.com/the-best-ful…