Script Modification for Answer Highlighting

I need a JavaScript script modified to change the color of highlights from green to grey. The script is currently used on a website and utilizes JavaScript function manipulation for highlighting.

Requirements:
- Modify existing JavaScript to change highlight color
- Ensure functionality remains intact after modification
- Test on the website to confirm proper operation

Ideal Skills and Experience:
- Proficiency in JavaScript
- Experience with website scripting
- Strong debugging skills