基于CSS实现元素融合效果

<template>
  <div class="parentBox">
    <div class="contantBox"></div>
  </div>
</template>
<style lang="less" scoped>
.parentBox {
  height: 100%;
  background: rgb(31, 31, 31);
  padding: 100px;
  @keyframes filterBallMove {
    50% {
      left: 140px;
    }
  }
  @keyframes filterBallMove2 {
    50% {
      right: 140px;
    }
  }
  .contantBox {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 300px;
    height: 200px;
    filter: contrast(20);
  }
  .contantBox::before {
    content: "";
    position: absolute;
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: olive;
    top: 40px;
    left: 80px;
    z-index: 2;
    filter: blur(6px);
    box-sizing: border-box;
    animation: filterBallMove 4s ease-out infinite;
  }
  .contantBox::after {
    content: "";
    position: absolute;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: green;
    top: 60px;
    right: 40px;
    z-index: 2;
    filter: blur(6px);
    animation: filterBallMove2 4s ease-out infinite;
  }
}
</style>

<template>
  <div class="parentBox">
    <div class="contantBox">
      <h1>hello Word!</h1>
    </div>
  </div>
</template>
<style lang="less" scoped>
.parentBox {
  height: 100%;
  background: rgb(31, 31, 31);
  padding: 100px;
  .contantBox {
    width: 100%;
    height: 100%;
    position: relative;
    padding: 4em;
    filter: contrast(20);
    overflow: hidden;
    background: rgb(0, 0, 0);
    h1 {
      font-family: Righteous;
      color: white;
      font-size: 4rem;
      text-transform: uppercase;
      line-height: 1;
      animation: letterspacing 3s infinite alternate ease-in-out;
      display: block;
      position: absolute;
      left: 50%;
      top: 50%;
      transform: translate3d(-50%, -50%, 0);
      letter-spacing: -2.2rem;
    }
  }
  @keyframes letterspacing {
    0% {
      letter-spacing: -2.4rem;
      filter: blur(0.3rem);
    }
    50% {
      filter: blur(0.5rem);
    }
    100% {
      letter-spacing: 0.5rem;
      filter: blur(0rem);
      color: #fff;
    }
  }
}
</style>