Tyfy Bootstrap (TyBs) is an enhanced version of Bootstrap 4. The tools for modular scale, baseline grid, and intelligent margins from the Tyfy framework are combined with Bootstrap's grid system and user interface components.
TyBs has been created according to Bootstrap's theming guide. Functions and mixins from the Tyfy framework are used to customize Bootstrap's SASS variables and provide some additional utilities.
The result is theme that can be applied to an existing Bootstrap 4 project with little change to the HTML structure or class attributes.