为什么这个 CSS 转换在锚点内的 SVG 上不起作用

I'm trying to transition the fill and path of an embedded SVG object, however this doesn't seem to work (Code Pen here):

SVG:

<a class="simple-link svg-link" href="">
  Some Text
  <svg version="1.1" id="next-page-icon" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
      viewBox="0 0 25 25" enable-background="new 0 0 25 25" xml:space="preserve" preserveAspectRatio="xMinYMin meet">
    <circle class="the-background" cx="12.5" cy="12.5" r="12.5"/>
    <g>
      <path class="the-icon"  d="M16.088,11.421l-3.404,3.362l-3.418-3.362v-1.204l3.418,3.444l3.404-3.444V11.421z"/>
     </g>
  </svg>
</a>

萨斯:

a
{
  width:200px;
  height:200px;
  overflow: hidden;

  @include transition(color, 1s);
  @include transition(background, 1s);

  svg
  {
    width:200px;
    height:200px;

    .the-background
    {
      @include transition(fill, 1s);
      fill: grey;
    }

    .the-icon
    {
      @include transition(fill, 2.5s);
    }
  }

  &:hover
  {
    color: red;
    background: black;
    .the-background
    {
      fill: black;
    }

    .the-icon
    {
      fill: red;
    } 

  }
}

为什么悬停时填充没有动画效果?

推荐答案

过渡不起作用的原因是因为它在链接内.

/* This goes within `a { ...` */
&:hover + svg { /* Or use ~ to select all */
  .the-background
  {
    fill: black;
  }

  .the-icon
  {
    fill: red;
  } 
}