Increasing contrast on comments about images

Can anyone advise how I might increase the contrast on the form for posting comments about an image? I am using the DCO Comment attachment plugin and the theme I am using is Twenty Twenty-Four. When you click on an image in the gallery it is displayed on a black background, which is fine – but the comment form has a very dark background too, and the prompt to “Write a comment” is quite faint. The only way I have found to improve it is to increase the brightness on my screen, but from an end-user perspective that’s not reasonable. I cannot see any settings or template or pattern covering this facility, so would be glad for a bit of guidance from more expert people than me! Thanks

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