This is a button built with TailwindCSS - https://tailwindcss.com/docs/installation

<a href="/" class="inline-flex rounded-md shadow-sm bg-purple-700">
  <button
    type="button"
    class="inline-flex items-center px-4 py-2 border border-transparent text-base leading-6 font-medium rounded-md text-white bg-rose-600 hover:bg-rose-500 focus:border-rose-700 active:bg-rose-700 transition ease-in-out duration-150 cursor-not-allowed">
    <svg
      class="animate-spin -ml-1 mr-3 h-5 w-5 text-white"
      xmlns="http://www.w3.org/2000/svg"
      fill="none"
      viewBox="0 0 24 24"
    >
      <circle
        class="opacity-25"
        cx="12"
        cy="12"
        r="10"
        stroke="currentColor"
        stroke-width="4"
      ></circle>
      <path
        class="opacity-75"
        fill="currentColor"
        d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"
      ></path>
    </svg>
    Button
  </button>
</a>