how to configure nginx to serve static site over https?

I have a static html site that is working normal over http, but is not working over https,I don't know what is wrong, here is my nginx config file:

server {    listen 80;    listen 443 ssl;    root /var/www/site.com/site;    index index.html index.htm index.nginx-debian.html;    server_name site.com www.site.com;    ssl_certificate /etc/nginx/ssl/site.com/site.com;    ssl_certificate_key /etc/nginx/ssl/site.com/myserver.key;    ssl_prefer_server_ciphers on;    location / {            try_files $uri $uri/ =404;    }

}