How to disable ssl on particular url on nginx - nginx

Question

I need help with some nginx configuration. So please help. So here is my situation.
my domain: rtechmedia.com
1) I want all the request of http:// www.rtechmedia.com redirect to https:// www.rtechmedia.com
2) I want all the request of https:// rtechmedia.com to https:// www.rtechmedia.com
3) But i want that the style folder and its content located at www.rtechmedia.com/styles/* should redirect to http:// www.rtechmedia.com/styles/* instead of https:// www.rtechmedia.com/styles/*
I am noob in nginx so please give in details. And note i put space in url because of low reputation. So ignore it
I am able to achieve 1) and 2) but not 3 so help me with that.
server {
listen 80;
server_name www.rtechmedia.com;
return 301 https://www.rtechmedia.com$request_uri;
}
server {
listen 80;
server_name rtechmedia.com;
return 301 https://www.rtechmedia.com$request_uri;
}
server {
listen 443 ssl;
server_name www.rtechmedia.com;
root /home/forge/www.rtechmedia.com;
ssl_certificate /etc/nginx/ssl/www.rtechmedia.com/11369/server.crt;
ssl_certificate_key /etc/nginx/ssl/www.rtechmedia.com/11369/server.key;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
index index.html index.htm index.php;
charset utf-8;
location / {
try_files $uri $uri/ /index.php?$query_string;
}
location = /favicon.ico { access_log off; log_not_found off; }
location = /robots.txt { access_log off; log_not_found off; }
access_log off;
error_log /var/log/nginx/www.rtechmedia.com-error.log error;
error_page 404 /index.php;
location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php5-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
}
location ~ /\.ht {
deny all;
}
}