Below is a container-fluid, which is just what I usually call a full-width stripe.
It contains a row of responsive columns that uses lg and md device column sizing.
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Below is a container, which on a large screen looks like what I usually call centered fixed-width content.
However, when you resize the browser window, you will see it scales down across the breakpoints to center the content different screen sizes.
That's actually very cool.
It contains a row of responsive columns that uses lg, md, and sm device column sizing.