Well, I’ve been here 4 days less than you, so take anything I say with a grain of salt.
I like the subject, and the page layout itself looks good. My only question would be why you used so much inline styling, rather than using the CSS sheet for most of it. You could, in your second div tag, you call it a class of jumbotron, but there is no class statement in CSS for it. You used inline background color to set it. Add or change your current classes to move some of those inlines off to the CSS section.
You can also set an h1 and img styles in the css, add a couple more class statements, and you’ll be able to strip out a ton of “style=:…” statements.
HTML is a markup language, meaning that you put basic documents (data) in it, and offload most of the styling (looks) to the CSS, instead of forcing the issue in the document. The idea between separating the two is so that your document can stay the same but look completely different by changing the CSS page
You might also use margin statements to be able to strip out some of those
tags. That will clean up your HTML even more.
Try some of these changes, and I’d love to take a look at the next version.