remove grey background on link clicked in ios safari / chrome / firefox

Latest versions of iOS are ignoring RGBA colors for some reason.

To remove it, I ended up having to use the following:

-webkit-tap-highlight-color: transparent;

As documented here: https://developer.mozilla.org/en-US/docs/Web/CSS/-webkit-tap-highlight-color

Webkit has a specific style property for that: -webkit-tap-highlight-color.

Copied from: http://davidwalsh.name/mobile-highlight-color—

/* light blue at 80% opacity */
html {
    -webkit-tap-highlight-color: rgba(201, 224, 253, 0.8);
}

/* change it for a div that has a similar background-color to the light blue tap color */
.blueDiv {
    -webkit-tap-highlight-color: rgba(251, 185, 250, 0.9);
}

If you want to remove the highlight completely—

.myButton {
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}