URL 扩展隐藏：重写与重定向

我已经阅读了很多问题和答案，但我无法决定哪一个更好或如何使用这些扩展隐藏方式的组合。
我想要的是就是有一个像这样的url重写堆栈溢出！那么我还应该做什么才能遵守这些规则：

url: example.com/file.anyEXT...  show content of => 404
url: example.com/unknown-Cat...  show content of => 404

url: example.com/cat1            show content of => example.com/cat1/index.php
url: example.com/cat1/index.php  show content of => 404
url: example.com/cat1/any...any  show content of => 404
url: example.com/cat1/11/title   show content of => example.com/cat1/single.php  (post id 11)

但我的 htaccess 文件就像这样：

url: example.com/file.anyEXT     
     show content of => example.com/index.php  (should show 404)

url: example.com/unknown-Cat
     show content of => example.com/index.php  (should show 404)

url: example.com/unknown-Cat/
    show broken content of => index.php => cant load css and js => (should show 404)

url: example.com/file.anyEXT/
     show broken content of => index.php => cant load css and js => (should show 404)

url: example.com/cat1 
     show content of => example.com/cat1/index.php (works fine!)

url: example.com/cat1/index.php
     show content of => example.com/cat1/index.php (should show 404)

url: example.com/cat1/any...any
     show content of => 404  (works fine!)

url: example.com/cat1/11/title
     show content of => example.com/cat1/single.php  (post id 11) (works fine!)

我拥有的

mydomain-|
         |
         |
         |__cat1-|__.htaccess  // cat1 htaccess
         |       |__index.php
         |       |__single.php
         |
         |__cat2-|__.htaccess // cat2 htaccess
                 |       |__index.php
                 |       |__single.php
                ...
                 |__.htaccess  // root htaccess
                 |__index.php  // home-page 

我的 htaccess 基于最建议的方式：

<IfModule mod_rewrite.c>

# Enable Rewrite Engine
RewriteEngine On
RewriteBase /

<files ".htaccess">
order allow,deny
deny from all
</files>    
Options All -Indexes

# Redirect from www.
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
RewriteRule ^(.*)$ http://example.com/$1 [L,R=301]

# Removes index.php from ExpressionEngine URLs
RewriteCond %{THE_REQUEST} ^GET.*index\.php [NC]
RewriteRule (.*?)index\.php/*(.*) /$1$2 [R=301,NE,L]

# Directs all EE web requests through the site index file
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php/$1 [L]

</IfModule>

这是我在根文件夹中使用的，在所有子文件夹中我有两个文件index.php and single.php我在每个子文件夹中都有这样的 .htaccess ：

Options +FollowSymLinks
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /cat1/

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(\d+)/(.+?)/?$ single.php?id=$1&title=$2 [L,QSA]

</IfModule>

您可以使用：

DocumentRoot/.htaccess:

<IfModule mod_rewrite.c>

<files ".htaccess">
order allow,deny
deny from all
</files>    
Options All -Indexes

RewriteEngine On
RewriteBase /

# Redirect from www.
RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
RewriteRule ^(.*)$ http://example.com/$1 [L,NE,R=301]

# 404 for index.php in URL
RewriteCond %{THE_REQUEST} /index\.php[\s?/] [NC]
RewriteRule ^ - [L,R=404]

</IfModule>

/cat1/.htaccess:

Options +FollowSymLinks
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /cat1/

RewriteCond %{THE_REQUEST} /index\.php[?\s] [NC]
RewriteRule ^index\.php$ - [L,R=404]

RewriteRule ^(\d+)/([^/]+)/?$ single.php?id=$1&title=$2 [L,QSA]

</IfModule>