.animate-letter span {
  opacity: 0;
  transform: translateY(20px);
  display: inline-block;
}

.animate-letter.animate span {
  animation: fadeInUp 0.6s ease forwards;
}

  /* 1文字ずつ遅延（最大20文字程度） */
  .animate-letter span:nth-child(1) { animation-delay: 0.05s; }
  .animate-letter span:nth-child(2) { animation-delay: 0.1s; }
  .animate-letter span:nth-child(3) { animation-delay: 0.15s; }
  .animate-letter span:nth-child(4) { animation-delay: 0.2s; }
  .animate-letter span:nth-child(5) { animation-delay: 0.25s; }
  .animate-letter span:nth-child(6) { animation-delay: 0.3s; }
  .animate-letter span:nth-child(7) { animation-delay: 0.35s; }
  .animate-letter span:nth-child(8) { animation-delay: 0.4s; }
  .animate-letter span:nth-child(9) { animation-delay: 0.45s; }
  .animate-letter span:nth-child(10) { animation-delay: 0.5s; }
  .animate-letter span:nth-child(11) { animation-delay: 0.55s; }
  .animate-letter span:nth-child(12) { animation-delay: 0.6s; }
  .animate-letter span:nth-child(13) { animation-delay: 0.65s; }
  .animate-letter span:nth-child(14) { animation-delay: 0.7s; }
  .animate-letter span:nth-child(15) { animation-delay: 0.75s; }
  .animate-letter span:nth-child(16) { animation-delay: 0.8s; }
  .animate-letter span:nth-child(17) { animation-delay: 0.85s; }

  @keyframes fadeInUp {
    0% {
      opacity: 0;
      transform: translateY(20px);
    }
    100% {
      opacity: 1;
      transform: translateY(0);
    }
  }