the code includes 2 js files with tens of lines, I can not post all here,
please click the link to see:

Part 2 is for show/hide text - if click on More text
Part 3 is for changing text - from more to less

I simply replace code of part 3 with More text of part 2 to generate part 1,
Part 1 is for both changing text and show/hide text,
but Part 1 almost becomes Part 3 - show/hide text does not work again.

please have a look.
all can be downloaded from:
which can be executed on your local PC.