Update docs/classic-ui/theming/color-mode.md

themes --> modes

Co-authored-by: Steve Piercy <[email protected]>

Author: toalba

docs/classic-ui/theming/color-mode.md

@@ -12,7 +12,11 @@ myst:
 # Color modes
 
 Bootstrap 5.3 has introduced [Color Modes](https://getbootstrap.com/docs/5.3/customize/color-modes/).
-This chapter is a guide for how to implement color themes in Plone 6.1.
+This chapter is a guide for how to implement color modes in Plone 6.1.
+
+```{versionadded} Plone 6.1
+```
+
 
 
 (preferred-color-modes-label)=