You will need to add the Bootstrap Framework to your page. Unfortunately only Bootstrap is recognised (and Framework 7 for mobile is also available). Would be great to see other Frameworks implemented as only Bootstrap is very limiting so we maintain a Dreamweaver subscription so we can work on other projects which do not use Bootstrap. We would love to drop the subscription one day and work solely within Wappler… We see a lot of Material designs among others so Material support would be my next suggestion. Will have to put a Feature Request together…