To use dynamic classes you will need to have a page parameter or another datasource in your page where the steps are nested. If that is the case you can use dynamic classes to change based on a value. Lets say you have an entity Steps with an attribute enumeration status, which is the datasource. If the status is 'active' you want class 'active-step' on your step.
To do that fill in:
if $currentObject/status = 'Active'
After that you can style the classes using SCSS.
Hope that helps
In the wizard, the container uses the dynamic class with the if condition takes as sequence wise it will work i have added the condition below
if $currentObject/Sequence = 1
else if $currentObject/Sequence > 1
I Hope this helpful for you.