svg 图标变色原理

SVG 图标可以自由变色，原理在于 fill="currentColor" 这个属性，可以根据父级的 color 来决定自己的 color

<?xml version="1.0" encoding="utf-8"?>
<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
     style="margin: auto; display: block; shape-rendering: auto; animation-play-state: running; animation-delay: 0s;"
     width="200px" height="200px" viewBox="0 0 100 100" preserveAspectRatio="xMidYMid">
  <g transform="rotate(0 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.9166666666666666s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(30 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.8333333333333334s"/>
    </rect>
  </g>
  <g transform="rotate(60 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.75s" repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(90 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.6666666666666666s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(120 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.5833333333333334s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(150 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.5s" repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(180 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.4166666666666667s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(210 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.3333333333333333s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(240 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.25s" repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(270 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.16666666666666666s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(300 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="-0.08333333333333333s"
               repeatCount="indefinite"/>
    </rect>
  </g>
  <g transform="rotate(330 50 50)" style="animation-play-state: running; animation-delay: 0s;">
    <rect x="47" y="24" rx="3" ry="6" width="6" height="12" fill="currentColor"
          style="animation-play-state: running; animation-delay: 0s;">
      <animate attributeName="opacity" values="1;0" keyTimes="0;1" dur="1s" begin="0s" repeatCount="indefinite"/>
    </rect>
  </g>
  <!-- [ldio] generated by https://loading.io/ -->
</svg>