better explanation for the component

Author: tiye

README.md

@@ -1,10 +1,38 @@
 
-React Stack Modal(WIP)
+React Stack Modal
 ----
 
 Demo http://ui.talk.ai/react-stack-modal
 
-`autoFocus: true` may break entering transition, add requestAnimation frame to by pass.
+### Design Purpose
+
+Ideas behind this component: [New modal built for React called react-stack-modal](https://hashnode.com/post/new-modal-built-for-react-called-react-stack-modal-cik1bmmif00054c53wtyxlk9u)
+
+State of modals and popovers are managed inside the store, so Controller will have full access to modals and it makes sophisticated logics possible. And the cost is we need quite some boilerplate code.
+
+### Usage
+
+This component is based on [`actions-recorder`](https://github.com/jianliaoim/actions-recorder).
+
+```bash
+npm i --save react-stack-modal
+```
+
+Steps to use this modal:
+
+* Setup `actions-recorder`
+* Setup `modalStack: []` in store as the default modal list
+* Connect actions `modal/add modal/remove modal/content-click` to `updater/modal.coffee`
+* Mount `ModalStack` in component tree and wire up events
+* Pick what you need in `main.css` and add in your project
+
+Browse [`app/`][app] folder for details. Well this is a library designed for heavy use of modals and popovers. It may be over complicated.
+
+[app]: https://github.com/jianliaoim/react-stack-modal/tree/master/app
+
+### Troubleshooting
+
+* `autoFocus: true` may break entering transition, add `requestAnimationFrame` to bypass.
 
 ### Develop