源码
<div class="number">404</div>
  
<style>
body {
  display: -webkit-box;
  display: flex;
  flex-flow: row wrap;
  align-content: center;
  justify-content: center;
}
div {
  width: 100%;
  text-align: center;
}
.number {
  background: #fff;
  position: relative;
  font: 900 30vmin 'Consolas';
  letter-spacing: 5vmin;
  text-shadow: 2px -1px 0 #000, 4px -2px 0 #0a0a0a, 6px -3px 0 #0f0f0f, 8px -4px 0 #141414, 10px -5px 0 #1a1a1a, 12px -6px 0 #1f1f1f, 14px -7px 0 #242424, 16px -8px 0 #292929;
}
.number::before {
  background-color: #673ab7;
  background-image: radial-gradient(closest-side at 50% 50%, #ffc107 100%, rgba(0, 0, 0, 0)), radial-gradient(closest-side at 50% 50%, #e91e63 100%, rgba(0, 0, 0, 0));
  background-repeat: repeat-x;
  background-size: 40vmin 40vmin;
  background-position: -100vmin 20vmin, 100vmin -25vmin;
  width: 100%;
  height: 100%;
  mix-blend-mode: screen;
  animation: moving 10s linear infinite both;
  display: block;
  position: absolute;
  content: "";
}
@-webkit-keyframes moving {
  to {
    background-position: 100vmin 20vmin, -100vmin -25vmin;
  }
}
@keyframes moving {
  to {
    background-position: 100vmin 20vmin, -100vmin -25vmin;
  }
}
</style>本文内容仅供个人学习/研究/参考使用,不构成任何决策建议或专业指导。分享/转载时请标明原文来源,同时请勿将内容用于商业售卖、虚假宣传等非学习用途哦~感谢您的理解与支持!