.htaccess不加载css和js

I have 2 blog files one is blogdetail.php and bloglist.php. What i want to make is if someone enters on a link like this

http://mysite.com/blog

to open bloglist.php and when someone enters to

http://mysite.com/blog/7

to open blogdetail.php?id=7. My .htaccess so far looks like this

Options +FollowSymLinks
RewriteEngine On
RewriteRule ^blog/([0-9]+)$ blogdetail.php?id=$1 [NC,L]
RewriteRule ^([a-zA-Z]+)$ $1.php [NC,L]
ErrorDocument 404 /404.php

but the problem is when i enter on blog/7, the page opens but the css does not load. Is there a way to make this work without using absolute paths to css and js? Thank you, Daniel!

Link your css file with / at beginning, and all will be fine.

you are missing this rules in .htaccess

Options +FollowSymLinks
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^blog/([0-9]+)$ blogdetail.php?id=$1 [NC,L]
RewriteRule ^([a-zA-Z]+)$ $1.php [NC,L]
ErrorDocument 404 /404.php