Mar 31 
from Verou
Dark mode in 5 minutes, with inverted lightness variables
This is a fine approach, and you'll likely want to do that for at least part of your colors eventually. 1However, even in the most disciplined of designs, not every color is a CSS variable. 1You often have colors declared inline, especially grays (e.g. the footer color in our example). 1This means that adding a dark mode is taxing enough that you may put it off for later, especially on side projects. 1
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