Pretty Permlinks on NGINX for WordPress – CentOS 7

I am trying to activate pretty permalinks on my wordpress installation, but no success. I’m changing this file /etc/nginx/conf.d/default.conf

I tried the following:

server{   
 if (!-e $request_filename) { rewrite ^.*$ /index.php last;

server {
if ($host ~* ^myhost.com$) {
    rewrite ^(.*) http://www.myhost.com$1 permanent;
    break;
} 

location / {
        try_files $uri $uri/ /index.php?q=$request_uri;
}

But none of these worked :(. Here is my full file:

 server {
    listen       80;
    server_name  example.com;
    return       301 http://www.example.com$request_uri;

}


    server {
    listen       80;
    server_name  www.example.com;

     note that these lines are originally from the "location /" block
    root   /usr/share/nginx/html;
    index index.php index.html index.htm;

    location / {
    root   /usr/share/nginx/html;
           index  index.php index.html index.htm;
           try_files $uri $uri/ /index.php?$args;      

    }
    error_page 404 /404.html;
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/html;
    }

    location ~ .php$ {
        try_files $uri =404;
        fastcgi_pass unix:/var/run/php-fpm/php-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;  
      }
    }

Can you help me please?

Thanks a lot.