Hello, @gray_b,
I am sorry, but do you want to reduce the image width on the single blog page? Am I Right? if yes then please use the below code for this in the Theme Options >> Theme Custom CSS >> Global at the bottom of the CSS box.
@media(min-width:991px){
.single-post .wp-picture{width:50% !important; margin-left:auto !important;}}
Then save settings and check back to your site after clearing the browser cache.
The result will look like this: https://postimg.cc/NKbN5qCQ you can see that the category text appears full, not half with the image.
Regards 8Themes Team.