Document rem as CSS unit

diff --git a/docs/reference/gtk/css-properties.xml b/docs/reference/gtk/css-properties.xml
index 09fcc0b3434994ebb47a299c66edd73a48207c65..3b80b4ae8e17af217e53ab11089e37e487679b9f 100644 (file)
--- a/docs/reference/gtk/css-properties.xml
+++ b/docs/reference/gtk/css-properties.xml
@@ -53,7 +53,7 @@ We use <literallayout> for syntax productions, and each line is put in a <code>
       The following basic datatypes are used throughout:
     </para>
 
-<literallayout><code>〈length〉 = 〈number〉 [ px | pt | em | ex | pc | in | cm | mm ]</code>
+<literallayout><code>〈length〉 = 〈number〉 [ px | pt | em | ex |rem | pc | in | cm | mm ]</code>
 <code>〈percentage〉 = 〈number〉 %</code>
 <code>〈angle〉 = 〈number〉 [ deg | grad | turn ]</code>
 <code>〈time〉 = 〈number〉 [ s | ms ]</code>
@@ -65,6 +65,11 @@ We use <literallayout> for syntax productions, and each line is put in a <code>
       which case they are resolved using the inherited font size value.
     </para>
 
+    <para>
+      The rem unit is resolved using the initial font size value, which is
+      not quite the same as the CSS definition of rem.
+    </para>
+
     <para>
       A common pattern among shorthand properties (called 'four sides') is one
       where one to four values can be specified, to determine a value for each