diff --git a/normalize.css b/normalize.css
index 94b03c7..771c8f3 100644
--- a/normalize.css
+++ b/normalize.css
@@ -296,6 +296,15 @@ textarea {
     margin: 0; /* 3 */
 }
 
+/**
+ * Re-apply the `font-weight` to avoid modifying the default UX, and because
+ * the default cannot be changed in Chrome and Safari on OS X.
+ */
+
+optgroup {
+    font-weight: bold;
+}
+
 /**
  * Address Firefox 4+ setting `line-height` on `input` using `!important` in
  * the UA stylesheet.
diff --git a/test.html b/test.html
index 51dda7b..ef13851 100644
--- a/test.html
+++ b/test.html
@@ -300,6 +300,13 @@
                 <p><label><input type="checkbox"> Checkbox input</label></p>
 
                 <p><label>Select field <select><option>Option 01</option><option>Option 02</option></select></label></p>
+                <p><label>Select with optgroup
+                  <select>
+                    <optgroup label="Optgroup label">
+                    <option>Option 01</option>
+                    <option>Option 02</option>
+                  </select>
+                </label></p>
                 <p><label>Textarea <textarea cols="30" rows="5" >Textarea text</textarea></label></p>
             </fieldset>