Update footer CIP text for rosetta sites. (#250)

* Add dark color to text if background is white.

* Lint css.

* Restore empty line.

* Use css only approach.

mu-plugins/blocks/global-header-footer/postcss/footer/logos.pcss

@@ -115,7 +115,7 @@
 		margin-bottom: 0;
 		font-family: serif; /* MrsEaves doesn't support non-latin characters well. */
 		font-size: 20px;
-		color: #4f5357;
+		color: rgba(255, 255, 255, 0.25);
 		text-transform: uppercase;
 		letter-spacing: 0.1em;
 
@@ -125,3 +125,9 @@
 		}
 	}
 }
+
+.wp-block-group.global-footer {
+	&.has-white-background-color span.global-footer__code_is_poetry {
+		color: #8f8f8f;
+	}
+}