How to make Nook Color or biblio Leaf to read Chinese epub file

Nook Color and biblio Leaf are two different ebook reader devices. one is TFT display and the other is EPD display. However, they are built on Android system and use Adobe Reader Mobile System Library as reader engine, so we can modify the css file in epub to make reader software force to use system font as rendering font, and then it will be successful to open epub and display Chinese.

So, How to modify the css file ? I just made an example for you, you need to know the knowledge about CSS, you will know what I do.

1. Take 蝸居.epub file as example
2. extract stylesheet.css
3. add following codes into css file
@font-face {
  font-family:"ek1epub";
  src:url(res:///system/fonts/DroidSansFallback.ttf);
}
4. search "font-family:" on the rest of css file, replace old name with "ek1epub"
5. add the modified stylesheet.css into epub file
6. copy the modified epub into device
7. for NookColor, open the file, you will find it still can not display correct Chinese, and then you should click the font setting and click the "OK"(I forgot the setting name). You will find the Chinese displaying correctly.
8. for biblio Leaf, if it can not display correct Chinese, you should reboot the device to try again.