Change Pencil Icon

Sorry for re-asking a question that’s been asked in various variations before, but I need help replacing the pencil icon.
Read half a dozen posts, failed to find in docs, tried different things recommended, can’t crack it.

Managed to get it swapped on individual posts and category pages that are set to “single author” mode, but it doesn’t work on category pages set to grid layout.

Here’s the code recommend elsewhere that’s doing most of what I want:

.blog-meta span.iconfont {
background-image: url(https://thetachisjsu.com/wp/wp-content/uploads/2016/04/OXCoatofArms.png);
background-size: contain;
background-repeat: no-repeat;
background-position: center center;
}

.blog-meta span.iconfont:before { display: none; }

And here’s what I tried doing to make the fallback image on grid mode swap.

span.slider-fallback-image {
background-image: url(https://thetachisjsu.com/wp/wp-content/uploads/2016/04/OXCoatofArms.png);}

Please advise.

P.S. Why is it a pencil icon, anyway? That’s the universal symbol for “click to edit” and that’s not what it does. And why’s it so hard to change? Seems like virtually *everybody* would want to change it from a weird pencil. Consider this another request to make this a click-to-customize setting. Thanks.