[gtksourceview] classic.xml: set foreground/background

[Christian Hergert <chergert src gnome org>]

commit 033d90b089febc6ea0b87c040fb489dac78421c8
Author: Christian Hergert <chergert redhat com>
Date:   Mon Oct 11 17:44:05 2021 -0700

    classic.xml: set foreground/background
    
    Now that we have a dark variant, we can specify the foreground/background
    for this style specifically. In the future we'll provide APIs to help
    switch between them based on dark/light preference of the toolkit.

 data/styles/classic.xml | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/data/styles/classic.xml b/data/styles/classic.xml
index 7b84d6ab..24c4b8d4 100644
--- a/data/styles/classic.xml
+++ b/data/styles/classic.xml
@@ -30,6 +30,7 @@
 
   <!-- Palette -->
   <color name="white"      value="#FFFFFF"/>
+  <color name="black"      value="#000000"/>
   <color name="blue"       value="#0000FF"/>
   <color name="magenta"    value="#FF00FF"/>
   <color name="violet"     value="#6A5ACD"/>
@@ -41,6 +42,9 @@
   <color name="yellow"     value="#FFFF00"/>
   <color name="purple"     value="#A020F0"/>
 
+  <style name="text"                        foreground="black" background="white"/>
+  <style name="line-numbers"                foreground="black" background="white"/>
+
   <!-- Global Settings -->
   <style name="draw-spaces"                 foreground="#babdb6"/>
   <style name="background-pattern"          background="#rgba(73,74,71,0.1)"/>