React-modal: Apply class to ReactModal__Overlay and ReactModal__Content with `className` (BEM style)

[coderberry]

We need to be able to add a class to the overlay portion of the css.. for example:

<Modal className="foo">...</Modal>

should render as:

<div class="ReactModal__Overlay ReactModal__Overlay--foo">
  <div class="ReactModal__Content ReactModal__Content--foo">
    ...
   </div>
</iv>

[mzabriskie]

@cavneb your use case is now supported, with a slight change:

<Modal className="myContentClass" overlayClassName="myOverlayClass"/>

Will result in:

<div class="ReactModal__Overlay myOverlayClass">
  <div class="ReactModal__Content myContentClass">
    ...
   </div>
</div>

[glifchits]

could we support a style prop for inline CSS in JS? I'm talking about:

var modalStyles = {
   left: 80,
   right: 80
};

return <Modal style={modalStyles} />;