Inconsistent card sizings when filtering

**Is your feature request related to a problem? Please describe.**
The margin and padding changes when filtering between milestones

**Describe the solution you'd like**
Preferably fixed sizes for each user's card view stack

**Additional context**


Start by reproducing the margin and padding changes when filtering between milestones, then trace the card view stack and its layout styles. Done means each user's card view keeps consistent sizing across those filters; the issue does not name a file or test to run.

Written by the indexing model from the issue text.