apply more styles to our icons - fixes #1081

the way we replace icons, the `ti` class gets removed, so those styles
were not applied; we always add a `ph-lg` class, so we select on that
one

I've left the `ti` selectors to hopefully make future merge conflicts
clearer

packages/frontend-embed/src/style.scss

@@ -101,7 +101,7 @@ rt {
 	}
 }
 
-.ti {
+.ti, ph-lg {
 	width: 1.28em;
 	vertical-align: -12%;
 	line-height: 1em;