add mkt-prompt element

![screen shot 2014-12-18 at 6 05 00 pm](https://cloud.githubusercontent.com/assets/674727/5499226/7038bf22-86e0-11e4-9834-51fe33050cce.png)

@mstriemer @spasovski 
fragile af, but…

```js
document.querySelector('#' + root.id + ' > section');
```

if only you could get an element's unique CSS selector. [some](https://github.com/ericclemmons/unique-selector) [have](https://github.com/fczbkk/css-selector-generator) [tried](http://stackoverflow.com/questions/8588301/how-to-generate-unique-css-selector-for-dom-element).