RewriteEngine On

<IfModule mod_headers.c>
    Header set Access-Control-Allow-Origin "*"
</IfModule>

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} (.+)/$
RewriteRule ^ %1 [R=301,L]

RewriteCond %{REQUEST_FILENAME} !-d 
RewriteCond %{REQUEST_FILENAME}\.php -f 
RewriteRule ^(.*)$ $1.php

RewriteRule ^([\s\S]+)$ tag.php?tag=$1&%{QUERY_STRING}