theme.lessby clicking the "Edit theme.less"-button. For bootstrap 4 fonts should be imported in the
custom.scss. Here you can import fonts via URL in this way:
.lessfiles for bootstrap 3 and the
.scssfiles for bootstrap 4 and uploading them later again enables for continuing on your styling in the theme builder in future.
@font-size-baseto 16px in the "Typography" section. To change the default of bootstrap 4 to 14px, set the
$font-size-baseof the "Typography" section to 0.875rem.