I have started to work with Angular Material 6. But I was not able to find out good CSS helper classes for that. My google search showed me Materializecss library. But it seems different front-end library even though they have mentioned it is based on Material Design. So can you tell me what was that? Can I use both on the same project? Why we don't have helper classes for Angular material?
e.g. class="left-align"
CSS helper libraries are for people who want to use CSS without having to write it themselves, because a lot of style patterns are very common. They can be very useful when they provide what you need. Helper classes are usually designed to be used with standard HTML and merely apply style to an element. Angular Material is about components, or custom elements, which usually have a more complex DOM structure than just a single element. You can apply helper classes to Angular Material components, but they aren't always going to work as you might hope.
IMO, it would be better to invest your time in understanding the features built into Angular Material and related libraries like Angular FlexLayout, than to try to get a library intended for use with standard HTML (like MaterializeCSS) to work properly with Angular Material.