KDA42/SynthTest ? reverse-engineered prompt

Build me a simple interactive web page with a clean layout and a nice modern look. I want it to work in the browser with a single HTML page, a stylesheet, and some JavaScript for the behavior.

Make it feel polished and fun, with responsive styling so it still looks good on mobile. Add a few small interactive elements so it doesn’t feel static, like buttons, hover effects, and something the user can click or change on the page. Keep the code easy to read and organized, and make sure the page loads without any extra setup.

If you need to make assumptions about the exact content, keep it simple and tasteful, and use current best practices. Feel free to look up current docs online if you need to.