diff --git a/public/css/module.less b/public/css/module.less
index 68e1a4d..0ba5dab 100644
--- a/public/css/module.less
+++ b/public/css/module.less
@@ -265,9 +265,9 @@ ul.bp {
         border: .15em solid white;
 
         &.size-s {
-            width: 1.15em;
-            height: 1.15em;
-            line-height: 1.15em;
+            width: 7em/6em;
+            height: 7em/6em;
+            line-height: 7em/6em;
         }
     }
 }