Non-existing Id and Class color change

I have searched for packages but i can not find anything.

Is there a packet or a way that i can do one of the following things:

  1. Make Atom recognize when a Id or Class does not exist and make it change the color to red.
  2. Make Atom show a list of already existing Classes or IDs.
  3. Make Atom autocomplete whenever i use id=" " or class=" ".

Here is an example in HTML5:

    <fieldset id="pedido">
        <legend>I want a Google Glass</legend>
        <p><label for ="cPed">I would like to get one as fast as possible</label></p>
        <p><label for ="cCor">Color:</label></p>
        <p><label for ="cQdt">Quantity:</label></p>
        <p><label for ="cTot"> Total Price: R$</label></p>

I want to find a way to make the “cPed” to change colors (red). Since an id for " for=" " " does not exist. If it did exist then the color would be green or any other color.

In other words I want Atom to do this: