Do you stay up till late in the night/early morning watching YouTube videos? If the answer is yes, then you can give your eyes a rest and turn the lights out.

Reddit discovered that YouTube has a secret dark mode that’s easy to activate. It appears to be available on the most recent version of Google Chrome (version 57 and above) — and once enabled, it seems to automatically apply to the remainder of the website, including the homepage and the dedicated channel pages.

Here’s how you can activate it:

• Open up the developer window by hitting Ctrl + Shift + I on Windows, or Option + Command + I on Mac
• Select the ‘console’ tab
• Paste in the following text: document.cookie="VISITOR_INFO1_LIVE=fPQ4jCL6EiE" and hit enter
• Close the developer window, refresh your browser, and the dark mode toggle is available in the main settings menu in the top right.
• Toggle 'Dark Mode' on, and you're settled.  

Now head to YouTube and kill all the lights.

This feature hasn’t yet been officially announced, but it’s part of a number of changes YouTube is testing for the website’s design.