diff --git a/group_vars/custom-sites.yml b/group_vars/custom-sites.yml
index 4269c382b..d80854d4e 100644
--- a/group_vars/custom-sites.yml
+++ b/group_vars/custom-sites.yml
@@ -220,6 +220,10 @@ galaxy_custom_sites:
     brand: StreetScienceCommunity
   - name: singlecell
     brand: Single Cell Omics
+    custom_css: |
+      #masthead {
+          background-color: #800080 !important;
+      }
   - name: humancellatlas
     brand: Human Cell Atlas
   - name: ml