Animated Gradient Border Pill Button

<a href="#" class="group overflow-hidden rounded-full pt-[1px] pr-[1px] pb-[1px] pl-[1px] relative">
  <span class="absolute inset-[-1000%] animate-[spin_2s_linear_infinite] bg-[conic-gradient(from_90deg_at_50%_50%,#E2E8F0_0%,#6366F1_50%,#E2E8F0_100%)] opacity-70"></span>
  <span class="inline-flex cursor-pointer items-center justify-center transition-all group-hover:bg-gray-800 text-base font-medium text-white bg-gray-900 w-full h-full rounded-full pt-2.5 pr-5 pb-2.5 pl-5 backdrop-blur-3xl">
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                    </span>
</a>