Export Highlights to HTML -> Format

Have started using the koreader export highlights feature, and am finding it extremely useful.

Is there any way to customize the template which is being used to format the resulting html? Specifically it would be great to be able to change the background color for the subject lines (with the date, chapter, and page no.).

Right now it is being set to #fffe00 which renders a bit too bright on my system - see attached.

Is there a template or any way to tweak this setting? Thank you!

Attached Thumbnails