Merge branch 'dev' of https://github.com/jerryc127/hexo-theme-butterfly into dev

layout/includes/footer.pug

@@ -22,9 +22,9 @@ if nav
       - const sinceYear = owner.since
       span.copyright
         if sinceYear && sinceYear != currentYear
-          != `©${sinceYear} - ${currentYear} By ${config.author}`
+          != `© ${sinceYear} - ${currentYear} By ${config.author}`
         else
-          != `©${currentYear} By ${config.author}`
+          != `© ${currentYear} By ${config.author}`
     if copyright.enable
       - const v = copyright.version ? getVersion() : false
       span.framework-info