Single Price Grid Component

So i have been having this problem for most of my challenges now, if you look into my "READ.md" form, you will see m screen shots of how i solved the process within my web dev. tools browser. it is most obvious that the final product looks way different compared to github pages. why is that? can someone give me some advice on browser formality. i want to solve the next challenge and this time getting it right on all browsers such as mine and github pages. i am not sure if i am explaining it right, but the screens are proof i definitely got the challenge right compared to how it looks on github pages.

Anyways, for the challenge, i would appreciate critical comments, i always look back at all my comments since its you guys who make me better each time. Thank you!