Function col_bp 

pub fn col_bp<F>(bp: Breakpoint, size: u8, f: F) -> Element<Div>
where
    F: FnOnce(Element<Div>) -> Element<Div>,

Create a responsive column.

Generates: <div class="col-{breakpoint}-{size}">...</div>

Example

use ironhtml_bootstrap::{grid::col_bp, Breakpoint};

let c = col_bp(Breakpoint::Md, 6, |c| c.text("Half on medium+"));
assert!(c.render().contains(r#"class="col-md-6"#));