add new class in tailwind css

1@tailwind base;
2@tailwind components;
3@tailwind utilities;
4
5@layer components {
6  .btn-blue {
7    @apply py-2 px-4 bg-blue-500 text-white font-semibold rounded-lg shadow-md hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-blue-400 focus:ring-opacity-75;
8  }
9}