Need an edge-to-edge design? Drop the parent
.container
or.container-fluid
.
Still if you need to remove padding from .row
and immediate child columns you have to add the class .no-gutters
with the code from @Brian above to your own CSS file, actually it's Not 'right out of the box', check here for official details on the final Bootstrap 4 release: https://getbootstrap.com/docs/4.0/layout/grid/#no-gutters