how to make a custom class using tailwindcss code example

Example 1: javascript replace class tailwindcss

<form>
  <input class="bg-gray-200 hover:bg-white hover:border-gray-300 focus:outline-none focus:bg-white focus:shadow-outline focus:border-gray-300 ...">
  <button class="bg-teal-900 hover:bg-teal-600 focus:outline-none focus:shadow-outline ...">
    Sign Up
  </button>
</form>

Example 2: javascript replace class tailwindcss

<form>
  <input class="bg-gray-200 hover:bg-white hover:border-gray-300 focus:outline-none focus:bg-white focus:shadow-outline focus:border-gray-300 ...">
  <button class="bg-green-500 hover:bg-teal-600 focus:outline-none focus:shadow-outline ...">
    Sign Up
  </button>
</form>