Every Website Should Have a Light and Dark Mode, they're Accessibility Features

Dark mode is important so people with sensitive eyes don't get eyestrain from navigating a website. Light mode is important so people whose eyes don't take in much light can clearly see a website. It's not a question of which is better; ideally, you should have both.

If you don't have the time or resources to design an entire nice-looking alternate color scheme for your website, you can use automated tools to make a dark color scheme; it doesn't have to be perfect, I appreciate any kind of dark mode because they're easy on my eyes. UserWay is one that I see many websites using, and it works well.