Hi Ulrike,
To change the color of active tab in nav drawer use the following css rule
#nav-drawer .list-group-item.active {
background-color: #yourcolourcode;
border-color: #yourcolourcode;
}According to your preferred colour, maybe you'll have to adapt font color as well.
As for "hidden to students", try this
.availabilityinfo .tag-info {
background-color: #yourcolourcode;
}It will change background-color for all types of restrictions in course page. If you want to change the colour only for "hidden to students restriction" the rule is
.availabilityinfo.ishidden .tag-info
Hope it helps
