Convert IIS rewrite to Nginx rewrite syntax?

I’d like to convert an IIS rewrite into Nginx rewrite syntax. I am looking for a way to rewrite a URL like /leaderboard into /pages.php?page=leaderboard. My IIS Rewrite Rule is:

<match url="^([^/]+)/?$" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="false">
  <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
  <add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
</conditions>
<action type="Rewrite" url="pages.php?page={R:1}" />

Current NGiNX Conf:

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

    server_name example.com www.example.com;
    return 302 https://$server_name$request_uri;
}

server {
    listen 443 ssl http2;
    listen [::]:443 ssl http2;
    ssl_certificate         /etc/ssl/cert.pem;
    ssl_certificate_key     /etc/ssl/key.pem;

    server_name example.com www.example.com;

        
    root /var/www/example.com/;
    index index.php index.html index.htm;


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

    location ~ .php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_split_path_info ^(.+.php)(/.+)$;
        fastcgi_pass unix:/var/run/php/php7.3-fpm.sock;
        fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include        fastcgi_params;
    }
}

Answer

server {
  rewrite ^/([^/]+)/?$ /pages.php?page=$1 break;
  ...
}

Matches (see tests):

❌  /
✅  /foo
✅  /foo/
❌  /foo/bar
❌  /foo/bar/baz