Hi, @jneal95.
If you just want to control the size of featured images when displaying on the post detail page (frontend side), you can achieve this by easily by adding “max-width” property with a desired value.
This value can be percentual (%) or in pixels (PX). Just note that percentual sizing will affect the size of every image differently (depending on its actual size). Now, with a fixed value in pixels you are able to prevent images from reaching a certain size, e.g. 900px.
You just need to add the “max-width” property to the corresponding CSS classes, as follows:
main.full-width .entry-thumb img { max-width: 912px; }
Hope that helps!
P.S. Instructions on how to add it:
1) On your WordPress Dashboard go to Appearance > Customize.
2) Locate “Additional CSS” Tab.
3) On the inside, if the file is not empty, go to the last line and add the CSS code referred above. If the file is empty, just copy the code in the first line.
4) Remember to click the “Publish” button to save your changes.
