Call out box: colour contrast issues

[msayoung]

The call out box allows for an optional image.

When set then we get a fade from a solid background to the image.

At small screen sizes the text overlaps with the fade, meaning the text no longer is high enough contrast with the background.

Example on the https://site3.demo.microsites.localgovdrupal.org/

Note: the text itself isn't contrasty enough even on a solid background - have noted that elsewhere.

Interestingly we got around this on localgov_base by hiding the image altogether.

https://demo.localgovdrupal.org/test-subsite-demo-all-components/example-page-different-page-components

[markconroy]

We have a width: 75% for the call out box content div in LocalGov Base, so the text does not cover any of the image.

https://github.com/localgovdrupal/localgov_base/blob/1.x/css/components/callout-box.css#L27

But that doesn't seem to be getting pulled through in the microsites base, or the fact that we hide the image in LocalGov Base. Maybe we've found a deeper issue with our CSS inheritance.