CSS按钮-跑马灯边框

请添加图片描述

思路很简单，实现方法有很多很多。但是大体思路与实现方法都类似：渐变色 + 动画，主要区别在动画的具体实现

0、HTML 结构

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>流光按钮</title>
</head>
<body>
  <div class="wrapper">
    <div class="btn">按钮</div>
  </div>
</body>
</html>

1-1、CSS 实现一

<style>
  *{
    padding: 0;
    margin: 0;
  }
  @property --rotate{
    syntax: "<angle>";
    initial-value: 20deg;
    inherits: false;
  }
  body{
    background-color: rgba(243, 243, 243);
  }
  .wrapper{
    position: relative;
    padding: 50px;
    background-color: rgb(0, 0, 0);
    z-index: -4;
    height: 500px;
  }
  .wrapper .btn{
    overflow: hidden;
    position: relative;
    text-align: center;
    border-radius: 7px;
    width: 100px;
    height: 50px;
    line-height: 50px;
    font-size: 22px;
    color: white;
    user-select: none;
    margin: 50px auto;
  }
  .btn::before{
    position: absolute;
    border-radius: 7px;
    content: "";
    inset: -20px;
    background: linear-gradient(var(--rotate), transparent 1%, rgb(255, 0, 191) , #00b7ff,  rgba(255, 0, 34, 0.719), transparent 98%);
    transform-origin: bottom left;
    z-index: -2;
    transition: all .4;
    animation: spin 2.4s linear infinite;
    transform-origin: 50% 50%;
  }
  .btn::after{
    content: "";
    position: absolute;
    border-radius: 8px;
    background-color: rgb(41, 41, 41);
    inset: 3px;
    z-index: -1;
  }

  @keyframes spin {
    0%{
      --rotate: 0deg;
    }
    100%{
      --rotate: 360deg;
    }
  }
</style>

1-2、CSS 实现二

  <style>
    *{
      padding: 0;
      margin: 0;
    }
    body{
      background-color: rgba(243, 243, 243);
    }
    .wrapper{
      position: relative;
      padding: 50px;
      background-color: rgb(0, 0, 0);
      z-index: -4;
      height: 500px;
    }

    .wrapper .btn{
      overflow: hidden;
      position: relative;
      text-align: center;
      border-radius: 7px;
      width: 100px;
      height: 50px;
      line-height: 50px;
      font-size: 22px;
      color: white;
      user-select: none;
      margin: 50px auto;
    }

    .btn::before{
      position: absolute;
      border-radius: 7px;
      content: "";
      inset: -20px;
      background: linear-gradient(0deg, transparent 1%, rgb(255, 0, 191) , #00b7ff,  rgba(255, 0, 34, 0.719), transparent 98%);
      transform-origin: bottom left;
      z-index: -2;
      transition: all .4;
      animation: spin 2.4s linear infinite;
      transform-origin: 50% 50%;
    }
    .btn::after{
      content: "";
      position: absolute;
      border-radius: 8px;
      background-color: rgb(41, 41, 41);
      inset: 3px;
      z-index: -1;
    }
    @keyframes spin {
      0%{
        transform: rotate(0deg);
      }
      100%{
        transform: rotate(360deg);
      }
    }
  </style>