CSS generic question

Hello Team,
This might be off topic question.
I tried multiple times to work on this CSS part, I am going wrong somewhere.
Could you please help?

I have two pages and one post

TV Room: http://wowdesigns.in/projects/xyz/tv-room/
Survey: http://wowdesigns.in/projects/xyz/survey/

Reading Room: http://wowdesigns.in/projects/xyz/category/reading-room/

If you can see the post header image(Banner/featured image)
It looks totally different from page's header image.

I am not sure where the CSS getting disturbed.

I am expecting the pages to have the images like it is displayed in post.

Thanks much.