Linking button to href not URL

I am using the Highend WP theme and need to link a popup href to a button. There is no URL because it will be linking to the popup plugin. Is there any way a non URL href can be added to a button?

This is the what I need to incorporate
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I have tried using the “raw HTML settings” with a built HTML button but I cannot center the button or add any CSS animation, etc so I would like to incorporate the href with a theme button.