Migrating to Bootstrap 4
Bootstrap 4 is a major rewrite and there are many changes to be aware of when upgrading from Bootstap 3. Here are the class name changes, tips and examples of migrating your Bootstrap 3.x code to Bootstrap 4.x.
Bootstrap's grid system consists of 12 units known as Columns (
.col-*-* CSS classes) that are used to layout content left-to-right across the viewport. Columns are contained within Rows (
.row CSS class) to create horizontal groups of columns. Rows are placed within a fixed or full-width Container (
.container-fluid, respectively) for proper alignment. Columns have padding that creates spacing (known as a "gutter") between the content in the columns.