body {
  margin: 0;
  height: 100vh;
  /* background-color: #0a0; 背景色（任意） */
  background: linear-gradient(135deg, #0a0, #6bffeb, #2b1b96);
  position: relative;
  overflow: hidden;
}

.container {
  perspective: 1000px; /* 遠近感を出す */
  position: relative;
  width: 100vw;       /* ビューポート幅いっぱいに */
  height: 100vh; 

  backdrop-filter: blur(100px);
  -webkit-backdrop-filter: blur(100px);
  background: rgba(255, 255, 255, 0.05); /* うっすら白のレイヤー */
  box-shadow: inset 0 0 100px rgba(255, 255, 255, 0.05);
}

.rotate-text1 {
  color :#ffffff;
  display: inline-block;
  font-size: 2em;
  animation: rotate3D 2s linear infinite;
  transform-style: preserve-3d;
  position: absolute;
  top: 25%;
  left: 20%;
}

.rotate-text2 {
  color :#ffffff;
  display: inline-block;
  font-size: 4em;
  animation: rotate3D 2s linear infinite;
  transform-style: preserve-3d;
  position: absolute;
  top: 5%;
  left: 70%;
  transition: top 0.3s ease, left 0.3s ease;
}

@keyframes rotate3D {
  from {
    transform: rotateY(0deg);
  }
  to {
    transform: rotateY(360deg);
  }
}