That is awesome. Khan definitely deserves a tribute, and Khan Academy is the only reason I was able to progress past college algebra. Looks great, too. He’d be happy with it. Also, it looks like your footer is coded almost exactly like the example. Bootstrap doesn’t have a footer class, so you did just what you should have done!
Looks good, adding ‘padding-top: 10px;’ will give you the gap between jumbotron and the top section (its on the sides as you’ve got the columns which adds gutters - i think)
I like the right aligned quote, also good shout on Khan Academy, that guy is great.