Ionic 4 Support

Does this support Ionic 4

I tried to follow your [guide from here](https://competenepal.com/beautiful-timeline-component-in-ionic-3/)

But suddenly I came across with the following css issue
`
@media screen and (max-width: map-get($grid-breakpoints,'lg')){
[ng]                                                            ^
[ng]       Undefined variable.
`

cannot find `$grid-breakpoints`