Earbuds Design & Prototype

I'm looking for a design for earbuds that would be ideal for fitness enthusiasts. The main feature I'm looking for is long battery life, while still remaining lightweight and comfortable. Additionally, I'd like these earbuds to have a minimalist design - one that is unobtrusive and stylish. Ideally, the design will also be timeless, so that it can remain popular even as technology and trends change.

This project includes the product design and a prototype, so the ideal candidate should have experience in engineering. The design I have in mind requires air conduction, not bone conduction.

Please let me know if you have any questions or need any additional information. I look forward to your proposals!