Curator: add mobile menu styling (#6146)

curator/parts/header.html

@@ -1,7 +1,7 @@
  <!-- wp:group {"align":"full","style":{"spacing":{"padding":{"bottom":"var(\u002d\u002dwp\u002d\u002dcustom\u002d\u002dgap\u002d\u002dvertical)","top":"var(\u002d\u002dwp\u002d\u002dcustom\u002d\u002dgap\u002d\u002dvertical)"}}},"layout":{"type":"flex","justifyContent":"space-between"}} -->
  <div class="wp-block-group alignfull" style="padding-top:var(--wp--custom--gap--vertical);padding-bottom:var(--wp--custom--gap--vertical)"><!-- wp:site-title {"style":{"typography":{"fontSize":"1.375rem"},"elements":{"link":{"color":{"text":"var:preset|color|foreground"}}}}} /-->
 
-	<!-- wp:navigation {"layout":{"type":"flex","setCascadingProperties":true,"justifyContent":"right","orientation":"horizontal"},"style":{"spacing":{"margin":{"top":"0"}}}} /--></div>
+	<!-- wp:navigation {"overlayBackgroundColor":"primary","overlayTextColor":"background","layout":{"type":"flex","setCascadingProperties":true,"justifyContent":"center","orientation":"horizontal"},"style":{"spacing":{"margin":{"top":"0"}}}} /--></div>
 	<!-- /wp:group -->
 	
 	<!-- wp:separator {"align":"full","style":{"spacing":{"margin":{"top":"0px","bottom":"0px"}}}} -->

curator/style.css

@@ -199,6 +199,14 @@ a:not(
 	text-underline-offset: 0.25rem;
 }
 
+/*
+ * Needed until https://github.com/WordPress/gutenberg/issues/39142 is fixed.
+ */
+ .wp-block-navigation__responsive-container.is-menu-open ul {
+	font-size: 2.75rem;
+	font-weight: 300;
+}
+
 /*
  * Hero post
  * The following style are required because variable fontSize doen't work in templates