[Gtk-3.18] Use old link color. Fixes #499

Author: khurshid-alam

gtk-3.0/scss/_global.scss

@@ -33,7 +33,7 @@ $question_fg_color: #fff;
 $question_bg_color: #673ab7;
 $error_fg_color: #fff;
 $error_bg_color: #f44336;
-$link_color: #3f51b5;
+$link_color: #fc6f5d;
 $success_color: #4caf50;
 $warning_color: #ef6c00;
 $error_color: #f44336;