This is awesome and adds a lot of information to the page :D Also, neat way to add them with partials!

I have some comments on styles/colors, but those are really minor details/up to the maintainer discretion.

I would ditch the "rust"/"orange" color that I originally used as a background for the header and maybe use black instead. black is more neutral and might go better with the green/yellow/red.

The css class is results-test in style.css.... on line 253.

(it is not the best class name now that I think of it ;p )

also for the bar height, maybe 20px instead of 40?

<div class="row" 
    style="background: linear-gradient(to right, 
            green {{ pass_percent }}%, 
              yellow {{ pass_percent }}% {{ skip_percent | plus: pass_percent }}%, 
              red {{ skip_percent | plus: pass_percent }}% {{ fail_percent | plus: pass_percent | plus: skip_percent }}%
            ); 
           height: 40px;">

I adjusted the colors a bit to contrast better with the background, also adjusted the bar height to 20px
and fixed the border color for the table

Looks great!