How can I get the HTML and CSS of my website's Header and Footer?

Wix does not currently have a function to get the HTML/CSS code from your website, wondering if anyone on here has an idea how I can still go about getting it or another workaround?

Background: We host a client portal on another site and would like clients to be able to seamlessly move back and forth without knowing they are leaving the website or returning to it. Without having the code we are not able to do this well.

THANK YOU

You don’t have access to the DOM and you can only work in javascript.

You can add html/css/js in an iFrame or as a custom tool in Tracking and Analytics.
https://support.wix.com/en/article/using-iframes-to-display-visible-content-on-your-site
https://support.wix.com/en/article/embedding-custom-code-to-your-site

You can get html from an iFrame and pass it to your Wix page through HTML Component and onMessage and postMessage.
https://www.wix.com/corvid/reference/$w.HtmlComponent.html
https://support.wix.com/en/article/corvid-working-with-the-html-element

If you have another website that you want to connect to, you can look at exposing your site to another API.
https://www.wix.com/corvid/reference/wix-fetch.html
https://support.wix.com/en/article/corvid-accessing-third-party-services-with-the-fetch-api

https://www.wix.com/corvid/reference/wix-http-functions.html
https://support.wix.com/en/article/corvid-exposing-a-site-api-with-http-functions

Corvid Example.
https://www.wix.com/corvid/forum/corvid-tips-and-updates/example-myapi-and-myapiclient

Plus, you can always look at using external datasets too.
https://support.wix.com/en/article/corvid-working-with-external-database-collections
https://www.wix.com/corvid/reference/external-database-collections.html