Make symbol white on iPhone?

Question

iPhone

There is an element in the background. It needs to be made translucent white. On desktop browsers everything is ok, but in Safari on the iPhone it is opaque black.
How to change the color of the symbol when displayed on the iPhone?

<div class="wrapper">
  <div class="close-lnk">
    <span class="close-symbol">&#10006;</span>
  </div>
</div>

.wrapper {
  background-color: #555da0;
  height: 100px;
  width: 100px;
  text-align: center;
}

.close-lnk {
 padding-top: 45px;
}

.close-symbol {
  color: white;
  opacity: 0.6;
}

Example:
https://jsfiddle.net/sf38txLj/1/
On desktop browsers everything is ok, on iPhone the symbol turns black.