diff --git a/themes/bootstrap3/less/bootstrap.less b/themes/bootstrap3/less/bootstrap.less
index 613c8b17cce0a76d1edada886458990d3f30c6f4..bf00503fd2db5ca7d17a4944acd339bdd250802e 100644
--- a/themes/bootstrap3/less/bootstrap.less
+++ b/themes/bootstrap3/less/bootstrap.less
@@ -198,25 +198,6 @@ footer {
   }
 }
 
-/* ------ Collections ------ */
-// Layout
-@media (min-width: 768px) {
-  .collection-hierarchytree { display: flex; }
-  .collection-hierarchytree .tree-panel,
-  .collection-hierarchytree #tree-preview {
-    flex-basis: 50%;
-    max-height: 75vh;
-    padding: 1rem;
-    overflow-y: auto;
-  }
-  #modal .collection-hierarchytree { display: block; }
-  #modal .tree-panel {
-    flex-basis: 100%;
-    padding: 0;
-  }
-  #modal #tree-preview { display: none; }
-}
-
 /* ------ Devtools ------ */
 .translation-output {
   width: 100%;
diff --git a/themes/bootstrap3/less/components/js-tree.less b/themes/bootstrap3/less/components/js-tree.less
index 4438f0e5c6bc7a72cd4e1a67769d68c285fda3f7..92ce82ac0cc6c025c3f8d021592cfbe5d33b5011 100644
--- a/themes/bootstrap3/less/components/js-tree.less
+++ b/themes/bootstrap3/less/components/js-tree.less
@@ -1,3 +1,20 @@
+@media (min-width: 768px) {
+  .collection-hierarchytree { display: flex; }
+  .collection-hierarchytree .tree-panel,
+  .collection-hierarchytree #tree-preview {
+    flex-basis: 50%;
+    max-height: 75vh;
+    padding: 1rem;
+    overflow-y: auto;
+  }
+  #modal .collection-hierarchytree { display: block; }
+  #modal .tree-panel {
+    flex-basis: 100%;
+    padding: 0;
+  }
+  #modal #tree-preview { display: none; }
+}
+
 .hierarchy-tree,
 .jstree-facet {
   /* jsTree arrows */