Custom breakpoint for ionic grid?

I’m trying to use Ionic Grid, but the breakpoints don’t go small enough.

i want to redefine the smallest breakpoint to be around 0-350px and second 400px. But following the docs there’s no indication where to put override

I tried putting in variables.scss, app.scss, and on the component level but nothing seems to actually change the breakpoints?

$grid-breakpoints: (
    sm: 0,
    md: 300px,
    lg: 1024px

  $grid-max-widths: (
    sm: 280px,
    md: 500px,
    lg: 960px

For example the above code doesn’t change the original breakpoints.