[CSS] Treebeard inline style override OSF existing style guide

[hellohaoyu]

Steps

1. Go to OSF meeting front page -- https://osf.io/meetings/
2. Use p-t-m in one DOM and check the value of padding-top in p-t-m

Expected

padding-top will be 25px

Fact

padding-top will be 30px

Notes

In OSF Meeting front page, the style from Treebeard will override classes from style guide. For example, in style guide, we define p-t-lg as 25px while it is defined as 30px in Treebeard inline style(inserted by webpack).