i have shared the Android method before, #TipsAndTricks
here's the rest
Enable dark mode for Chrome on Windows 10
1. Enter the Settings menu, choose 'Personalization' click 'Colors' and scroll down to the switch marked 'Choose your default app mode'.
2. Change this to 'Dark' and all apps with a native dark mode, including Chrome, will change color. There's no need to restart your browser.
Enable dark mode for Chrome on iOS
(iOS is trickier and it should be available to all in the next chrome update)
For the time being, you can use the Invert feature to achieve a similar effect.
1. Open 'Settings' and select 'General > Accessibility > Display accomodations'.
2. Toggle 'Classic Invert' to invert the colors of everything on your device's screen, or 'Smart invert' to leave images alone but invert everything else.
^^ continued
If there's no dark version available, the browser will invert the site's colors. Activating the second option means that the browser interface itself will turn dark
3. Tap the drop-down menu under each of these options and change the setting to 'Activated', then restart Chrome.
4. Now open the settings menu, tap 'Themes' and select 'Dark'. If you can't see the Themes option, restart Chrome again and it should appear
there are tons of new bug reports submitted inside Chromium Bug Tracker, which are somehow related with dark mode implementation in the iOS variant of Google Chrome.