3 column and sizing

Hello,

i was wondering if someone can help me out with this. basically, i want to make the footer flow down base on the content. if you view my blog at https://www.fusionrain.com/blog you will see what i mean.

i set up the height for the div rap2 to be px, if anyone know in another way for me to make the content auto flow i would really appreciate it.

thanks
solarpunk