diff --git a/.github/diy/patches/argon.patch b/.github/diy/patches/argon.patch
index 6d57cd9ec..6364593f4 100644
--- a/.github/diy/patches/argon.patch
+++ b/.github/diy/patches/argon.patch
@@ -1,3 +1,15 @@
+--- a/ucode/template/themes/argon/header.ut
++++ b/ucode/template/themes/argon/header.ut
+@@ -47,7 +47,7 @@
+ 
+ -%}
+ <!DOCTYPE html>
+-<html lang="{{ dispatcher.lang }}">
++<html lang="{{ dispatcher.lang }}"{% if (mode == 'dark'): %} data-darkmode="true"{% elif (mode == 'light'): %} data-darkmode="false"{% endif %}>
+ 
+ <head>
+ 	{% include("themes/" + theme + "/head_meta", { hostname: hostname, node: node, bar_color: bar_color, media: media }) %}
+
 --- a/luci-theme-argon/ucode/template/themes/argon/footer.ut
 +++ b/luci-theme-argon/ucode/template/themes/argon/footer.ut
 @@ -19,13 +19,6 @@