percentage values are relative to the nearest ancestor element

viewport units are always relative to the browser window

1. Using another domain name means that you'll be able to not have the cookies that are used on the main domain - which means that HTTP requests will be smaller
2. No need for a full PHP/.NET/JAVA server to serve static content!
3. Use another machine to serve the static content (Including some CDN) 
4. Use another web-server to serve the static content (something more lightweight and faster)

$("#element").keyup(function(event){
    if(event.keyCode == 13)
        someAction('param');
    }
});

background-position: right bottom;
background-position: 100% 100%;
background-position: bottom 0px right 0px;

background-position: right center;
background-position: 100% 50%;

background-position: left top;
background-position: 0% 0%;
background-position: left 0px top 0px

$res = preg_replace('/\\\\u([a-f0-9]{4})/e', "iconv('UCS-4LE','UTF-8',pack('V', hexdec('U$1')))", json_encode($this->response));

$res = json_encode($this->response, JSON_UNESCAPED_UNICODE);

JSON_UNESCAPED_UNICODE

<div class="action-button_toggle_menu nav-link dropdown-toggle btn btn-light username" href="#" id="…wnMenuLink"  data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" aria-pressed="false">

<span style="text-transform: uppercase;font-weight:550; font-size:38px">