support emoji (see https://github.com/riggraz/no-style-please/pull/69 for info)

_sass/no-style-please.scss

@@ -6,6 +6,7 @@
 
     &.ioda { filter: invert(0); }
   }
+.emoji { filter: invert(1); }
 }
 
 body[a="dark"] { @include dark-appearance; }
@@ -91,4 +92,4 @@ img {
   max-width: 100%;
   display: block;
   margin: 0 auto;
-}
+}