Ask HN: Need advice for a senior lead

I work as a lead in an organization.I started my career as a back end dev with Java / JEE and for the last three years started working on Front end technologies like angular,React JS etc. I find the front end as interesting yet very challenging. As a lead I have this dilemma on how to handle junior developers who are smart and more experienced in front end than me. I try myself to keep updated but it becomes challenging when it comes to lower level details especially css etc. Please advice on how to cope up with this situation and be an effective lead