The CSS folder will not work if you do not make the right notes, I recommend that you try to use the address in all CSSs with / up front, like this:
<link href="/css/estilo1.css">
<link href="/css/estilo2.css">
<link href="/css/estilo3.css">
Or absolute path:
<link href="http://site/css/estilo1.css">
<link href="http://site/css/estilo2.css">
<link href="http://site/css/estilo3.css">
Remember that the CSS folder has to be outside the ./atacado folder, if you are inside you will get in the way of using the ./mercado folder, if you want to keep inside the ./atacado folder it does not work you can try use the <base> tag inside ./mercado/index.php like this:
<html>
<head>
<base href="/atacado/">
...
Of course, if you are using include ...; to add header it might be better to use the absolute path as I mentioned above.
It's probably because you created a folder called ./atacado , also note that you added the folders in the rewrite
atacado/index.php?estado=$1&cidade=$2 [NC,L] <-- antes do index.php tem a pasta atacado
mercado/index.php?estado=$1&cidade=$2 [NC,L] <-- antes do index.php tem a pasta mercado
Probably the folder ./mercado or the file in ./mercado/index.php does not exist, I think you really want to point everything to index.php that is in the same folder as .htaccess, so the correct one would be:
RewriteEngine On
RewriteRule ^atacado/(.*)/(.*) index.php?estado=$1&cidade=$2 [NC,L]
RewriteRule ^mercado/(.*)/(.*) index.php?estado=$1&cidade=$2 [NC,L]
Now if you really want to point to a folder called the market and to a folder named wholesale, then you should make sure that both exist and that they are in lowercase letters (if it is like-unix), the structure expected by your% should be this:
./
├── .htaccess
├── atacado/
| └── index.php
└── mercado/
└── index.php
You should also check that there is no other .htaccess in the "market" and "wholesale" folders and also check if you have forgotten to add .htaccess
