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CSS Bootstrap 4 Basics (Retired) Getting to Know Bootstrap 4 Enhancing the Page

Spacing not working?

I've added mt-3 and mb-3 as per the Bootstrap documentation and it's not working. I see other people are having this same issue and I can't find a solution online. Please help?

Dane Parchment
Dane Parchment
Treehouse Moderator 11,021 Points

Please show us the code so we can properly debug it.


Try mb-5 because the p has already margin bottom defaut is mb-3

1 Answer

Dave McFarland
Dave McFarland
Treehouse Teacher

Hi Holly Logan

The current version of Bootstrap 4 (alpha 6) doesn't work the same as in the video. Here are the changes you'll need to make to get this to work:

  • Bootstrap no longer uses class names like this m-t-3 to define the location, size and type of spacing (padding or margin). They've decided to remove the first hyphen character, so the correct class name would be mt-3.
  • The spacing values discussed in the video no longer reflect full REM values. In other words, mt-3 does not add 3 rem to the top margin. It actually is just 1 rem. To get the spacing above the headline as seen in the video the top margin should be mt-5.
  • Adding a margin to the bottom of the headline no longer works -- due to a "collapsing margin" (Mastering Collapsing Margins) adding margin space to the bottom of the paragraph doesn't add any space. Instead use a class to add bottom padding to the paragraph: pb-3

The correct code for the headline and paragraph should be:

<h1 class="display-1 mt-5">Full Stack Conf</h1>
<p class="lead pb-3">Coming Soon, a One-day Conference About All Things JavaScript!</p>

I've updated the teacher's notes to describe these changes: https://teamtreehouse.com/library/enhancing-the-page and we'll be re-doing the affected videos once a stable beta version of Bootstrap 4 is released.