error loading mobile first

Everything was working normally, out of nowhere, after uploading an improvement to Python Anywhere, I opened the website on my cell phone and realized that this was happening, but I don’t know since when.
A few days ago everything was normal, and in my CSS files there were no significant changes in mobile first.
Has anyone seen or experienced something like this?

video link demonstrating what happens as soon as the page loads:

Welcome @MoisesAvilar !

I think you’re going to need to be more explicit about the issue you are experiencing. Please explain here what is wrong - what you are seeing that you’re not expecting to see. (Or, explain what you’re not seeing that you expect to see.)

I uploaded the wrong video link :confused:

but basically I created my CSSs to be mobile first, but I don’t know what I could have done that when I click to go to any page, it loads as mobile first according to how I left my CSSs but then the layout resizes as if it were a larger screen size