rainbow-background/README.md

rainbow-background - rainbow background.

# rainbow-background
 rainbow-background - rainbow background.
# rainbow-background Document
 Check out document: [rainbow-background Document](https://cnoctave.github.io/rainbow-background/index.html)
# How to translate rainbow-background Document into another language
 In ./docs directory, index.html is zh-CN simplified Chinese document. 
 For example, if you want to translate document into English.
 1. Copy index.html as another document with different language code as filename, 
 for example, en-US.html.
 2. Translate en-US.html into English.
 3. Add dropdown like the picture below to every *.html. 
 For example, add dropdown "en-US English".  
 ![the dropdown looking](./docs/translate_dropdown.png)  
 The code for adding dropdown is like the picture below.  
 ![the dropdown code](./docs/translate_dropdown_code.png) 
 4. PR to rainbow-background.