UI: Fix repo header issues

[silverwind]

I missed updating the .header-grid selector in #5945 which made a bunch of styles not apply. Fixed that and did a few small tweaks in turn.

Screenshot after fixes:

Fixes: #5985

[codecov-io]

Codecov Report

Merging #5995 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5995      +/-   ##
==========================================
+ Coverage   38.75%   38.76%   +<.01%     
==========================================
  Files         332      332              
  Lines       48938    48938              
==========================================
+ Hits        18967    18969       +2     
+ Misses      27225    27222       -3     
- Partials     2746     2747       +1

Impacted Files	Coverage Δ
models/unit.go	14.28% <0%> (+14.28%)	⬆️

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