api.conf

server {
    listen 80;
    listen [::]:80;

    root /var/www/html;
    index index.php index.html index.htm index.nginx-debian.html;
    server_name server_domain_or_IP;
    
    include /etc/nginx/additional_conf.d/header_options.conf;

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

    location /api {
        rewrite ^/api(.*)$ /api.php$1 last;
    }

    location ~ [^/]\.php(/|$) {
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        try_files $fastcgi_script_name =404;
        set $path_info $fastcgi_path_info;
        fastcgi_param PATH_INFO $path_info;
        fastcgi_index index.php;
        include fastcgi.conf;
        fastcgi_pass unix:/run/php/php7.0-fpm.sock;
    }

    location ~ /\.ht {
        deny all;
    }
}

header_options.conf

add_header Strict-Transport-Security "max-age=63072000; includeSubDomains; preload";
add_header X-Download-Options noopen;
add_header X-Permitted-Cross-Domain-Policies none;
add_header X-Frame-Options DENY;
add_header X-Content-Type-Options nosniff;
add_header X-XSS-Protection "1; mode=block";
add_header X-Robots-Tag none;

nginx.conf

user  nginx;
worker_processes  4;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

events {
    worker_connections  8096;
    multi_accept        on;
    use                 epoll;
}
worker_rlimit_nofile 40000;

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile           on;
    tcp_nopush         on;
    tcp_nodelay        on;
    keepalive_timeout  65;
    server_tokens on;

    gzip  on;
    gzip_vary on;
    gzip_min_length 10240;
    gzip_proxied expired no-cache no-store private auth;
    gzip_types text/plain text/css text/xml text/javascript application/x-javascript application/xml;
    gzip_disable "MSIE [1-6]\.";

    include /etc/nginx/conf.d/*.conf;
}

ssl_options.conf

ssl_protocols TLSv1.2;
ssl_prefer_server_ciphers on;
ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:DHE-RSA-AES256-SHA;
ssl_ecdh_curve secp384r1;
ssl_session_timeout  10m;
ssl_session_cache shared:SSL:10m;
ssl_session_tickets off; # Requires nginx >= 1.5.9
ssl_stapling on; # Requires nginx >= 1.3.7
ssl_stapling_verify on; # Requires nginx => 1.3.7