[gtk+] docs: css-overview: Don’t recommend broken syntax

[Daniel Boles <dboles src gnome org>]

commit b5afe75700bae2e8cb7d6a0a9f5d819b47cae050
Author: Daniel Boles <dboles src gnome org>
Date:   Sun Sep 3 12:07:35 2017 +0100

    docs: css-overview: Don’t recommend broken syntax
    
    Using this produced warnings about the Pango syntax of <Family> <size>
    being deprecated, and the size being invalid due to no unit specified.
    Also, that multi-word font family presumably wouldn’t work as expected.

 docs/reference/gtk/css-overview.xml |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/docs/reference/gtk/css-overview.xml b/docs/reference/gtk/css-overview.xml
index 3d8c8a1..1c3aed5 100644
--- a/docs/reference/gtk/css-overview.xml
+++ b/docs/reference/gtk/css-overview.xml
@@ -123,7 +123,7 @@ scale[.fine-tune]
       <programlisting><![CDATA[
 button, entry {
   color: #ff00ea;
-  font: Comic Sans 12
+  font: 12px "Comic Sans"
 }
 ]]></programlisting>
     </example>
@@ -216,7 +216,7 @@ notebook > entry {
       <title>Theme any widget within a GtkBox</title>
       <programlisting><![CDATA[
 box * {
-  font: Sans 20
+  font: 20px Sans
 }
 ]]></programlisting>
     </example>
@@ -225,7 +225,7 @@ box * {
       <title>Theme a label named title-label</title>
       <programlisting><![CDATA[
 label#title-label {
-  font: Sans 15
+  font: 15px Sans
 }
 ]]></programlisting>
     </example>