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<input type="radio" id="color" name="test" value="color">
<label for="color">color</label>
<input type="radio" id="fill" name="test" value="fill">
<label for="fill">fill</label>
<input type="radio" id="all" name="test" value="all" checked>
<label for="all">all</label>
<p><small>Choose a <code>transition-property</code> and then hover the logo to see the effect.</small></p>
<p class="parent">
  <svg xmlns="" width="96" height="96" viewBox="-2 0 94 96"><path fill="#fff" d="M48 8C26 8 8 26 8 48s18 40 40 40c14 0 26.2-7 33.4-18L69.7 58.4c-4 8-12 13.7-21.7 13.7-13.3 0-24-10.7-24-24s10.7-24 24-24c9.6 0 17.8 5.6 21.7 13.7L81.4 26C74.2 15 62 8 48 8z"></path><path class="demo"  d="M58.3 26.3l-32 32c2.4 5 6.4 9 11.4 11.4l32-32c-2.4-5-6.4-9-11.4-11.4z"></path></svg>
  <span class="demo"><abbr>css</abbr></span>
<p><small>As of 2016-06-02, Firefox seems to get <code>fill</code> right, but it even fades the path on <code>color</code>. Chrome does the latter, but it misses out on <code>fill</code>. Safari ignores the  SVG path transition altogether.</small></p>
<p><small>Must be related to currentColor and the cascade, I’ve also created <a target="_top" href="">a version without currentColor</a>, no issues there.</small></p>


                .parent {
  color: #d34b6c;
  fill: #d34b6c
.parent:hover {
  color: #bada55;
  fill: #bada55
.demo {
  color: currentColor;
  fill: currentColor;
  transition-duration: .5s;
  transition-timing-function: linear
input[value="color"]:checked ~ .parent .demo {
  transition-property: color
input[value="fill"]:checked ~ .parent .demo {
  transition-property: fill
input[value="all"]:checked ~ .parent .demo {
  transition-property: all
/* only the stuff above is important */
body { background: #202225; color: #fff; font-family: sans-serif }
main { width: 18em; margin: 1em auto }
label[for] { cursor: pointer }
small { color: #999 }
input { margin-left: 2ch }
svg { vertical-align: middle }
abbr { color: #fff }
.parent { padding: 1em; background: #000; border: 1px dashed #999; line-height: 7em; text-align: center }
a { color: #d34b6c }