Bootstrap HTML styling : I've never been good with CSS. I am especially bad with positioning. Some people claim they have poor sense of direction well i can say i have a very poor sense of positioning when it comes to CSS.

Anyway, is there anyway to add padding styles in the html itself?

    <img class="img-rounded" src="http://placehold.it/100x100" style="padding-top:10px;">

How do i add padding on all sides? Is this impossible? 

I'm using bootstrap and so far i've never needed any CSS so i'd like to keep it that way. I'm relearning PHP/codeigniter and i don't want to bite off more than i can chew since i'm already using bootstrap and other jquery plugins adding CSS on top of that would only add confusion to my already loose schedule. I really don't have a detailed plan on this project of mine so it's a really confusing ride.

I also would like to know, what's the limitations of bootstrap? So far any styling i've needed i got through w3school bootstrap and i've seen no need of CSS as of now so i would like to know where the line is drawn between CSS and bootstrap.