I am trying to add SSL in my Docker. Everything set up except for my nodejs app.

This is my nginx configuration

    map $http_user_agent $is_desktop {
        default 0;
        ~*linux.*android|windows\s+(?:ce|phone) 0; # exceptions to the rule
        ~*spider|crawl|slurp|bot 1; # bots
        ~*windows|linux|os\s+x\s*[\d\._]+|solaris|bsd 1; # OSes
    }

    map $is_desktop $is_mobile {
        1 0;
        0 1;
    }

    server {
        listen 443 ssl;
        server_name example.com;
        charset utf-8;
        if ($time_iso8601 ~ "^(\d{4})-(\d{2})-(\d{2})") {
            set $year $1;
            set $month $2;
            set $day $3;
        }
        access_log /usr/logs/nginx/lion/lion.$year-$month-$day.log;
        ssl_certificate     /etc/nginx/ssl/example.com/b2d6debd2142c643.crt;
        ssl_certificate_key /etc/nginx/ssl/example.com/example.key;


        location / {
            index index.html;
            if ($is_mobile) {

                root /usr/src/lion;

            }

            if ($is_desktop) {

                proxy_pass http://martinez:3000;
            }
            error_page 404 =301 /;
        }

        location /dist {
            alias /usr/src/martinez/dist;
            access_log off;
        }

        location /img {
            if ($is_desktop) {
                root /usr/src/martinez/dist;
                access_log off;
            }
        }

        error_page  405     =200 $uri;
    }

    server {
        listen 443;
        server_name www.example.com;
        return 301 $scheme://$host$request_uri;
    }

When I try to access this one, it will show a not secure on the URL address bar and this is probably because the proxy_pass is not in https. When I tried changing it into https I get a 502 Bad Gateway which I can't resolve. I already tried exposing and opening the ports on my docker-compose.yml

docker-compose.yml

martinez:
  restart: always
  build: ./martinez/
  expose:
    - "3000"
    - "443"
  ports:
    - "3000:443"
  tty: true
  env_file: .env

nginx:
  restart: always
  build: ./nginx/
  ports:
    - "80:80"
    - "443:443"
    - "3000:3000"
  links:
    - martinez:martinez