Because I do not understand the code, so to ask everyone. This tool looks like a direct reversal of the color of the page, some pictures will not be reversed, the idea is great. However, I found that since most web pages are white, the background is black when turned on. But pure black is obviously not good for vision and reading, so I wondered if there's any way to make the whole page grayer, such as # 1B1B1B (Adobe's black background).
Of course, I found that changing the two values can achieve the background color gray, but this will lead to the picture also followed by gray, because I am a visual designer, so to see the picture is very important to me.

Read the README, and you'll need to learn CSS and understand HTML documents.
https://github.com/alexanderby/darkreader/blob/master/README.md
I will add some experimental filters soon.
So, I've added SVG filter, Static Theme and Dynamic Theme modes to try. Dynamic Theme is the best one and will become default after some improvements.
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I will add some experimental filters soon.