110 — how to write to the DOM

document.createTextNode('...')                                                  

document.createElement("div")

function appendHtml(el, str) {
  var div = document.createElement('div');
  div.innerHTML = str;
  while (div.children.length > 0) {
    el.appendChild(div.children[0]);
  }
}

var html = '<h1 id="title">Some Title</h1>
<span style="display:inline-block; width=100px;">Some arbitrary text</span>';

appendHtml(document.body, html); // "body" has two more children - h1 and span.

document.body.insertAdjacentHTML("beforeend", theHTMLToInsert);

Here we add elements:

<div id="div-1" style="text-align:left;">                                       
</div>

→ docs.nginx.com/nginx/admin-guide/web-server/reverse-proxy/
Passing a Request to a Proxied Server

css detected: