All the Bootstrapping you not that for 2 hours, and even 2 weeks can not write. More precisely, write a draft of something
, and then another who knows how long the bugs will catch. And after about a month of debug will understand that it is time to do a global refactoring :)
Although the reference grid makes suspect that you don't need the whole library, but only the grid? If so, then Yes, it is possible and to write all these col-1, etc.
About customization - Bootstrap she responds well, only if your changes are in line with overriding variables: https://github.com/twbs/bootstrap/blob/master/scss...
And too bad if something harder/deeper (because of the architecture and historical reasons).