Increasing width of featured image with sidebar

I have several pages with a left sidebar menu and a featured image. When both of these are on a page the featured image scales with the size of the inner post content so it does not fill the main content area.
Is it possible to make the featured image the same width regardless of whether or not there is a sidebar?
I have been using the below additional CSS to drop the sidebar well to below the featured image which works but the featured image is still too narrow. (I have my featured image size locked to 200px height)
.well {
border: 0px;
margin-top: 200px;

Thank you

Hi @cmhttal,

I hope you are well today and thank you for your question.

It’s hard to achieve this just using CSS code and you have to develop PHP code in the child theme of Sparkling theme.

Developing custom code for custom functionality is beyond the scope of support that we provide here.

If you are not a developer then you can consider hiring a developer to develop it for you. You can hire a developer from any freelance site. Colorlib recommends the developer

Best Regards,