Fix navbar overlapping content (#92)

Fix navbar overlapping content

The navbar previously switched inconsistently to mobile layout which
meant between 1024 and 1087 screen width, it would overlap most of the
page making links unclickable.

Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/theme/pulls/92
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: 6543 <6543@obermui.de>
Co-Authored-By: silverwind <silverwind@noreply.gitea.io>
Co-Committed-By: silverwind <silverwind@noreply.gitea.io>

src/main.scss

@@ -72,7 +72,7 @@
   transition: all ease 300ms;
 }
 
-@media screen and (max-width:1087px){
+@media screen and (max-width:1023px){
   .navbar-menu{
     position: fixed;
     bottom: 0;