For many years, it seemed like columns were one of the toughest layout challenges web designers faced. It often took various hacks, such as clearfixes, to get them aligned and looking good. Thankfully, the advent of CSS Flexbox has helped to make this previously-difficult process a much simpler one. Because Flexbox was created with multi-container (columns or rows) layouts in mind, we’ve said goodbye to all of those old hacks. The result is that we can create some absolutely amazing…