Creates a collapsible block of content
Collapsible content
To create a collapsible block of content, create a container and add the data-role="collapsible" attribute. Using the data-content-theme attribute allows you to set a theme for the content of the collapsible.
Directly inside this container, add any header (H1-H6) or legend element. The framework will style the header to look like a clickable button and add a "+" icon to the left to indi