I’m 51 years old. I like to use dark mode to make the reading less aggressive to my eyes. But I’m facing difficulties to read gray text upon black background. Moreover, I can’t even see text selections when there’s daylight inside my office.
Your topic title mentions the IDE. I assume this is the VSCode editor? If so, there are some default themes you can use in preferences. Thete are, sadly, only a couple though. If none are suitable, then 15 of the best (their words) VSCode themes are showcased at https://www.spec-india.com/blog/vscode-themes.
The docs for VSCode have details on getting new themes from the extensions marketplace, and how to install them at Visual Studio Code Themes.
The above link also has information about customising a theme – in case you just need to change the text colours for example.