Safari Technology Preview now supports dark mode via `@media (prefers-color-scheme: dark)` in CSS media queries. 

Same should be supported in Electron apps to enable automatic light/dark mode switching.

shell/browser/atom_browser_client.cc
base::AutoLock auto_lock(process_preferences_lock_);
  auto it = process_preferences_.find(process_id);
  return it != process_preferences_.end() && it->second.sandbox;
}
bool AtomBrowserClient::RendererUsesNativeWindowOpen(int process_id) const {
  base::AutoLock auto_lock(process_preferences_lock_);
  auto it = process_preferences_.find(process_id);
  return it != process_preferences_.end() && it->second.native_window_open;
}
bool AtomBrowserClient::RendererDisablesPopups(int process_id) const {
  base::AutoLock auto_lock(process_preferences_lock_);
  auto it = process_preferences_.find(process_id);
  return it != process_preferences_.end() && it->second.disable_popups;
}
std::string AtomBrowserClient::GetAffinityPreference(
    content::RenderFrameHost* rfh) const {
  auto* web_contents = content::WebContents::FromRenderFrameHost(rfh);
  auto* web_preferences = WebContentsPreferences::From(web_contents);
  std::string affinity;
  if (web_preferences &&
      web_preferences->GetPreference("affinity", &affinity) &&
      !affinity.empty()) {
    affinity = base::ToLowerASCII(affinity);
  }
  return affinity;
}
content::SiteInstance* AtomBrowserClient::GetSiteInstanceFromAffinity(