Version 9.50 Dashboard - how to restore blue colors to portlets

I recently upgraded our instance from 9.32 to 9.50.

In 9.3x, we had high contrast between dark blue header lines in portlets while the bodies of the portlets were a back and forth of light blue and white.  It made for easy-on-the-eyes reading.

Now, in 9.50, the portlets are all white - header and body both which is a bit stark for my taste.

I would like to restore that earlier color scheme if there is a way...?