[gtk/matthiasc/for-master] colorbutton: Correct the css docs

[Matthias Clasen <matthiasc src gnome org>]

commit 6bd0dc3e783aa3aa0c9468a63d101e2504e70946
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Dec 23 09:03:07 2020 -0500

    colorbutton: Correct the css docs
    
    Mention the wrapper colorbutton node.

 gtk/gtkcolorbutton.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkcolorbutton.c b/gtk/gtkcolorbutton.c
index f4f8cc40fb..622cce0b60 100644
--- a/gtk/gtkcolorbutton.c
+++ b/gtk/gtkcolorbutton.c
@@ -58,8 +58,15 @@
  *
  * # CSS nodes
  *
- * GtkColorButton has a single CSS node with name button. To differentiate
- * it from a plain #GtkButton, it gets the .color style class.
+ * |[<!-- language="plain" -->
+ * colorbutton
+ * ╰── button.color
+ *     ╰── [content]
+ *]|
+ *
+ * GtkColorButton has a single CSS node with name colorbutton which
+ * contains a button node. To differentiate it from a plain #GtkButton,
+ * it gets the .color style class.
  */
 
 typedef struct _GtkColorButtonClass     GtkColorButtonClass;