Html Css tags

I have some basic knowledge of html / CSS, however I try to know how things work. In the attached image is an analysis of the elements taken by firebug. I note that the html code does not appear <div>, <class> marked with an arrow in the image. How these elements appear here?
Who is Participating?
Dan CraciunConnect With a Mentor IT ConsultantCommented:
You're using Bootstrap, so layout is automatically modified, depending on the user agent and browser's width.

How are we supposed to debug an image???
Paul MacDonaldConnect With a Mentor Director, Information SystemsCommented:
It's difficult to understand what you're asking.  Can you re-phrase what you mean by
"I note that the html code does not appear <div>, <class>. How these elements appear here?"

Do you think there's HTML in the page that's not being rendered?  Or do you think there's HTML being rendered and you don't understand why?
The new generation of project management tools

With’s project management tool, you can see what everyone on your team is working in a single glance. Its intuitive dashboards are customizable, so you can create systems that work for you.

rflorencioAuthor Commented:
In fact some rendered code is not in the html source code. By saying Dan Craciun should be to the use of the bootstrap.
GaryConnect With a Mentor Commented:
Probably because it is dynamically added by javascript
rflorencioAuthor Commented:
After research some examples I get it, thanks.
All Courses

From novice to tech pro — start learning today.