htaccess human readable - regex

Question

I have a site which already defined htaccess for making url nice
DirectoryIndex index.php
RewriteEngine On
RewriteBase /
Options -indexes
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule (.*) index.php
Everything works fine (there is cms in the root folder).
Now I want to create a folder inside root and make another rules for it:
DirectoryIndex index.php
RewriteEngine On
RewriteBase /
Options -indexes
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !tip [NC]
RewriteRule (.*) index.php [NC]
RewriteCond %{QUERY_STRING} ^$
RewriteRule ^tip/([^/]+)/? /tip/?id=$1
So I want to redirect everything from url: .../tip/?id=N -> ../tip/N
It seems to work fine, id is passed, data is loaded BUT. All the urls are wrong inside site (javascript, css). They aren't loaded.
Look at: http://wincode.org/tip/3
For example, code: <script defer src="js/filtrify.js"></script> produces: http://wincode.org/tip/js/filtrify.js but if you will try to load it in another tab, it will pass js/filtrify.js as id argument, I think. How to fix this?

Answer 1

A. Change your .htaccess code to this in $DOCUMENT_ROOT/.htaccess:
DirectoryIndex index.php
RewriteEngine On
RewriteBase /
Options -indexes
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule (?!^tip(/.*|)$)^.*$ /index.php [L,NC]
B. Change your .htaccess code to this in $DOCUMENT_ROOT/tip/.htaccess:
DirectoryIndex index.php
RewriteEngine On
RewriteBase /tip
Options -indexes
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteCond %{QUERY_STRING} ^$
RewriteRule ^([^/]+)/?$ /tip/?id=$1 [L,QSA]

Answer 2

I just improved little bit anubhava reply, this one is based on root folder example, but you can use same approach for other dir that you need.
DirectoryIndex index.php
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
Options -indexes
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule (?!^tip(/.*|)$)^.*$ /index.php [L,NC]
</IfModule>
<IfModule !mod_rewrite.c>
# Mod_rewrite not installed, redirect all 404 errors to index.php.
ErrorDocument 404 index.php
</IfModule>