For a static website:

    server {
        listen 80;
        listen [::]:80;
        server_name <example.com>;

        root /srv/http/<example.com>/www;
        index index.html;

        location / {
            try_files $uri $uri/ =404;
        }
    }

For a reverse proxied website:

    server {
        listen 80;
        listen [::]:80;
        server_name <example.com>;

        location = /favicon.ico {
            access_log off;
            log_not_found off;
        }

        location /theme_static/ {
            alias /some/static/files/dir/theme_static/;
        }

        location / {
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-Proto $scheme;
            proxy_pass http://127.0.0.1:<localport>;
        }
    }

For SSL stuff, add this to the body:

     listen 443 ssl http2;
     listen [::]:443 ssl http2;

     ssl_certificate /etc/letsencrypt/live/<cert-name>/fullchain.pem;
     ssl_certificate_key /etc/letsencrypt/live/<cert-name>/privkey.pem;
   
     add_header Content-Security-Policy "default-src 'self'; style-src 'self' 'unsafe-inline'";
     #add_header Content-Security-Policy "default-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'";
     add_header X-Frame-Options "SAMEORIGIN";       # 'always' if nginx > 1.7.5
     add_header X-Content-Type-Options "nosniff";   # 'always' if nginx > 1.7.5
     add_header X-Xss-Protection "1";
     # Enable STS with one year period (breaks http; optional)
     #add_header Strict-Transport-Security "max-age=31557600; includeSubDomains";


    if ($scheme = http) {
        return 301 https://$server_name$request_uri;
    }

    # Let's Encrypt SSL Certs
    location /.well-known/acme-challenge/ {
        root /var/www/letsencrypt;
        autoindex off;
    }


If your site is going to have inline Javascript (pretty common), you might need
to swith the Content-Security-Policy line to:

     add_header Content-Security-Policy "default-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'";