hidden-xs-down = d-none d-sm-block
hidden-sm-down = d-none d-md-block
hidden-md-down = d-none d-lg-block
hidden-lg-down = d-none d-xl-block
hidden-xl-down = d-none (same as hidden)
hidden-xs-up = d-none (same as hidden)
hidden-sm-up = d-sm-none
hidden-md-up = d-md-none
hidden-lg-up = d-lg-none
hidden-xl-up = d-xl-none
hidden-xs (only) = d-none d-sm-block (same as hidden-xs-down)
hidden-sm (only) = d-block d-sm-none d-md-block
hidden-md (only) = d-block d-md-none d-lg-block
hidden-lg (only) = d-block d-lg-none d-xl-block
hidden-xl (only) = d-block d-xl-none
visible-xs (only) = d-block d-sm-none
visible-sm (only) = d-none d-sm-block d-md-none
visible-md (only) = d-none d-md-block d-lg-none
visible-lg (only) = d-none d-lg-block d-xl-none
visible-xl (only) = d-none d-xl-block
web