If you want to embed code from another site into your own site, you have to
1) link it in OR 2) retrieve and parse it.
1) The typical solution for this was iframe. It's not simple, but you can use the width and height settings for the iframe with @meda css queries to obtain a measure of responsiveness.
2) If you have php as a tool, you can look at this stack overflow answer to get an idea how to retrieve the website code, then parse the code out.
for instance, if I wanted only the information after the closing head tag, I could do
// get the webpage source -- depends on allow_url_fopen
// see the previously mentioned stack overflow answer for alternates
$externalWebpage = file_get_contents('http://yoursite.com/your-page.html');
// split the webpage by </head>
$websiteSections = explode($externalWebpage, '</head>',);
// don't neglect to add the '</head>' back if you want to use that
// portion somewhere else
$head = $websiteSections[0] . '</head>';
$body = $websiteSections[1];
Assuming you went with the php solution, all this could be done in the backend of the site prior to generating the html. Further parsing is obviously possible, but depends on your knowledge of the external page's structure.
