Feedback on Humlix UI

I would be happy if you can take a moment and look at the UI of my application https://www.humlix.com and give some feedback on your first impression.
Humlix is for developers and testers, and the tool will generate tests for them. Either they create test requests manually, or they import, e.g., an OpenAPI spec.

I know it is hard just by looking at a screenshot, but any ideas or suggestions would be highly appreciated around the colors, layout, etc.