Bootstrap 4 ships with a `_custom.scss` file for easy overriding of default variables in `/scss/_variables.scss`. Copy and paste relevant lines from there into the `_custom.scss` file, modify the values, and recompile your Sass to change our default values. **Be sure to remove the `!default` flag from override values.**
Customize Bootstrap 4 with our built-in custom variables file and easily toggle global CSS preferences with new `$enable-*` Sass variables. Override a variable's value and recompile with `npm run test` as needed.
| `$spacer` | `1rem` (default), or any value > 0 | Specifies the default spacer value to programmatically generate our [spacer utilities](/utilities/spacing/). |
| `$enable-grid-classes` | `true` (default) or `false` | Enables the generation of CSS classes for the grid system (e.g., `.container`, `.row`, `.col-md-1`, etc.). |