Hi Phil
Please don't hesitate to reach out to us if you have any questions 😉
The page's dimensions and scaling are controlled via the viewport <meta> tag by settings various attributes within this tag. You can find this tag declared in this file of T4 framework:
/plugins/system/t4/themes/base/html/layouts/t4/index.php
I recommend to override this file in template so it will not be affected when you update new version of T4 framework. To do this, you copy file: /plugins/system/t4/themes/base/html/layouts/t4/index.php
and paste into this directly in template folder: /templates/ja_purity_iv/html/layouts/t4/ (create this path if it doesn't exist now)
Open this file: /templates/ja_purity_iv/html/layouts/t4/index.php, then look for this line of code:
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=yes"/>
You can search for how to work with above attributes: maximum-scale, user-scalable, ... or simply change it to:
<meta name="viewport" content="width=device-width, initial-scale=1">
Hope this helps!