adjust scaleY parameter

src/client/styles/scss/_mixins.scss

@@ -143,7 +143,7 @@
       width: ($size * 0.707);
       height: ($size * 0.707);
       background-color: inherit;
-      transform: scaleY(0.5774) rotate(-45deg);
+      transform: scaleY(0.6) rotate(-45deg);
     }
 
     @if $box-shadow != 0 {