Stylesheet not loaded because of MIME type

'm working on a website that uses elixir to compile and browser sync to keep the browser synchronised with my changes.

The elixir and phoenix framework task compiles everything properly, but on the website, I’m unable to see any style, and the console shows this error message:

Refused to apply style from ‘http://localhost:4000/dashboard’ because its MIME type (‘text/html’) is not a supported stylesheet MIME type, and strict MIME checking is enabled.

help me how to solve this error in elixir.