Does Chrome not support CSS variables within media queries?
I have the following CSS:
:root {
 --threshold-lg: 1200px;
 --threshold-md: 992px;
 --threshold-sm: 768px;
 --sidebar-margins: 10px;
}
@media(min-width: var(--threshold-sm)) {
  .sidebar {
    top: var(--sidebar-margins);
    bottom: var(--sidebar-margins);
  }
}
In both Chrome 50 and Chrome Canary (52), I see no margin adjustment. In Safari 9.1, it works as expected.
 
     
    