diff --git a/src/pyj/book_list/book_details.pyj b/src/pyj/book_list/book_details.pyj
index c8507d7fab..947f628e68 100644
--- a/src/pyj/book_list/book_details.pyj
+++ b/src/pyj/book_list/book_details.pyj
@@ -16,7 +16,7 @@ from book_list.library_data import (
 )
 from book_list.router import back, home, open_book, report_a_load_failure
 from book_list.theme import (
-    browser_in_dark_mode, get_color, get_color_as_rgba, get_font_size
+    color_scheme, get_color, get_color_as_rgba, get_font_size
 )
 from book_list.top_bar import add_button, clear_buttons, create_top_bar, set_title
 from book_list.ui import query_as_href, set_panel_handler, show_panel
@@ -155,8 +155,7 @@ if window?:
 
 def adjusting_sandboxed_html(html, extra_css):
     color = get_color_as_rgba('window-foreground')
-    cs = 'dark' if browser_in_dark_mode() else 'light'
-    css =  f'\n\n:root {{ color-scheme: {cs} }}\n\nhtml, body {{ overflow: hidden; color: rgba({color[0]}, {color[1]}, {color[2]}, {color[3]}) }}'
+    css =  f'\n\n:root {{ color-scheme: {color_scheme()} }}\n\nhtml, body {{ overflow: hidden; color: rgba({color[0]}, {color[1]}, {color[2]}, {color[3]}) }}'
     if extra_css:
         css += '\n\n' + extra_css
     # allow-same-origin is needed for resizing and allow-popups is needed for
diff --git a/src/pyj/book_list/comments_editor.pyj b/src/pyj/book_list/comments_editor.pyj
index 8fab1af25b..a9f63cdd6a 100644
--- a/src/pyj/book_list/comments_editor.pyj
+++ b/src/pyj/book_list/comments_editor.pyj
@@ -4,7 +4,7 @@ from __python__ import bound_methods, hash_literals
 
 from elementmaker import E
 
-from book_list.theme import browser_in_dark_mode, get_color, get_color_as_rgba
+from book_list.theme import color_scheme, get_color, get_color_as_rgba
 from dom import add_extra_css, build_rule, clear, svgicon
 from gettext import gettext as _
 from iframe_comm import IframeClient, create_wrapped_iframe
@@ -396,8 +396,7 @@ class Editor:
             self.pending_set_html = html
             return
         rgba = get_color_as_rgba('window-foreground')
-        cs = 'dark' if browser_in_dark_mode() else 'light'
-        self.iframe_wrapper.send_message('set_html', html=html, color_scheme=cs, color=f'rgba({rgba[0]},{rgba[1]},{rgba[2]},{rgba[3]})')
+        self.iframe_wrapper.send_message('set_html', html=html, color_scheme=color_scheme(), color=f'rgba({rgba[0]},{rgba[1]},{rgba[2]},{rgba[3]})')
 
     def get_html(self, proceed):
         self.get_html_callbacks.push(proceed)
diff --git a/src/pyj/book_list/theme.pyj b/src/pyj/book_list/theme.pyj
index 622b9f4422..648cea02e1 100644
--- a/src/pyj/book_list/theme.pyj
+++ b/src/pyj/book_list/theme.pyj
@@ -81,6 +81,10 @@ def browser_in_dark_mode():
     return window.matchMedia('(prefers-color-scheme: dark)').matches
 
 
+def color_scheme():
+    return 'dark' if browser_in_dark_mode() or document.documentElement.style.colorScheme is 'dark' else 'light'
+
+
 def css_for_variables():
     input_css = '''
         input, textarea {