Single Course Page is overlapping my menus and content

Hi Team

I need a little help. Seems to be a standard complaint, an while I have found part solutions I am battling with the Single Course Content screen which hides the header, menu and footer. The headers for LP overlaps the content.

I have found a part solution from this blog below
https://www.ugenegrg.com.np/learnpress-lesson-template-changes/

I suspect I am having a small issue as their is one line of code I could not find in the
File #3 – plugins/learnpress/templates/single-course/content-item/header.php – holds the top search form namely this one: <div class=”content-item-scrollable”> to <div class=”content-item-scrollable-custom”>
I have implemented all other code nd it appears to work 99%. I am battling to get hold of the original author and hence hoping someone here has a solution.
His code works great except for a few small issues:
In Tablet and Phone views the left Course curriculum block pushes the main content over and it goes off to the right, past the header. It LP std this is normally hidden. What can I add to the Custom CSS to hide this when it is in responsive mode for phone and tablet.

Also in Explorer there is not scroll bar now.

If I cannot fix this code, perhaps someone has a suggestion to display the course content within the template in an acceptable way. This appears to be a common problem.

The page I need help with: [log in to see the link]