Hey Umar,
If you want to do this in a model page within a Mx 7.x project, you could use a widget like EnumClass to set the correct CSS class to the container depending on the wizard status for that step. You then have to store the progress (active, finished, new) in an enum and connect the corresponding CSS classes to it, so that the CSS class will be set dynamically.
If you work in a 8.x project you can use ‘dynamic classes’ of a container object to set the CSS class based on an enumeraton or any expression and you would not need any widget.
Regards,
Ruud