Question

What us the meaning of collapsed..... ​

Answer 1

$\huge\bf\underline{\red{Y}\green{o}\orange{u} \pink{r}\:\red{a}\purple{n}\blue{s}\orange{w}\red{e} \purple{r}}$

Just add data-toggle="collapse" and a data-target to the element to automatically assign control of one or more collapsible elements. The data-target attribute accepts a CSS selector to apply the collapse to. Be sure to add the class collapse to the collapsible element.

Hope this much helps uh ❣️