looking for the location of $domain variable in the default vhost file in a Marketplace Wordpress setup

Hi I’m trying to find where the value for $domain is stored on a Marketplace wordpress install

during installation it asks for you domain and a few other things and then it updates files

The /etc/apache2/sites-available/000-default.conf file is below

UseCanonicalName On

<VirtualHost *:80> ServerAdmin webmaster@localhost

    ServerName $domain
    ServerAlias www.$domain

    DocumentRoot /var/www/html

    <Directory /var/www/html/>
        Options FollowSymLinks
        AllowOverride All
        Require all granted
    </Directory>

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

</VirtualHost>

I’m tryng to find where the value $domain is stored I checked the only spot I know of /etc/apache2/conf-available/fqdn.conf and it’s not there

I know I could directly change that value ServerName [NEW-DOMAIN-NAME] but would like to know where that variable is being stored in case it affects other things.

also side question where is the value for ${APACHE_LOG_DIR} stored at.

Thanks