diff --git a/packages/theme-default/src/step.css b/packages/theme-default/src/step.css
index 7795580c9..abd447210 100644
--- a/packages/theme-default/src/step.css
+++ b/packages/theme-default/src/step.css
@@ -64,6 +64,7 @@
 
       > * {
         line-height: inherit;
+        vertical-align: middle;
       }
     }