Color change in the preview mode

Hi everyone hope you are doing good.
On my webflow project, I ented to have a full blue background, but it appears that on 2 of my 6 pages are reacting quite differently by putting a white background to my header (I don’t understand, I’ve checked and everything is good in the designer (i guess). That’s why I need some help. (problems appear on the blog and contact page.)

I hope someone can help me, but no stress, Have a very good day. Thanks a lot

Here is my site Read-Only: Webflow - moosse website