Something wrong when I upload my default.php to my website

I am trying to make my landing website page.
but after I uploaded my default.php, the page didn't appear as I designed before.

this is the different:
(above: What I designed, below: how it appeared on my web):
pls check this image

Can you help me identify what was wrong with that?
p.s: I upload the whole structural folder and file as on my pc to my web file manager.