diff --git a/theme/boost/scss/moodle/core.scss b/theme/boost/scss/moodle/core.scss
index 3830831b6b8..1eb9d9d5c05 100644
--- a/theme/boost/scss/moodle/core.scss
+++ b/theme/boost/scss/moodle/core.scss
@@ -223,33 +223,6 @@ img.activityicon {
     vertical-align: middle;
 }
 
-.boxaligncenter {
-    margin-left: auto;
-    margin-right: auto;
-}
-
-.boxalignright {
-    margin-left: auto;
-    margin-right: 0;
-}
-
-.boxalignleft {
-    margin-left: 0;
-    margin-right: auto;
-}
-
-.boxwidthnarrow {
-    width: 30%;
-}
-
-.boxwidthnormal {
-    width: 50%;
-}
-
-.boxwidthwide {
-    width: 80%;
-}
-
 .headermain {
     font-weight: bold;
 }