diff --git a/static/katex.less b/static/katex.less
index 260980150..4d1b9fa6c 100644
--- a/static/katex.less
+++ b/static/katex.less
@@ -161,17 +161,17 @@ big parens
     .reset-scriptscriptstyle.scriptstyle { font-size: 1.5em; }
     .reset-scriptscriptstyle.scriptscriptstyle { font-size: 1em; }
 
-    .baseline-align-hack-outer {
+    .baseline-align-hack-outer() {
         display: inline-block;
         vertical-align: top;
     }
 
-    .baseline-align-hack-middle {
+    .baseline-align-hack-middle() {
         display: block;
         height: 0;
     }
 
-    .baseline-align-hack-inner {
+    .baseline-align-hack-inner() {
         display: inline-block;
     }