Escaping CSS digits, 0 is removed from CSS aggregated files
I think the code is valid.
Anyway due to lack of time i decided to ad an &quot;id&quot; to the class. So the html is now
&lt;div class=&quot;iconleft id-{{ child_id }}&quot;&gt;Text&lt;/div&gt;

And the css
.iconleft.id-109,
.iconleft.id-112,
.iconleft.id-110,
.iconleft.id-111,
.iconleft.id-120 {
  background: #B0CD00;
}

This is working for me.
But if somebody knows why aggregation removes the &quot;0&quot; please let me know.