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There is a conflict with your template's CSS styles. In your template.css file around line 1237 you have the following:
The static breaks it, so try adding

That's because your margin and padding need to be adjusted.
Here's an example of a way to adjust it, but you can find the best fit with experimentation:
Currently, we don't have a built in way to make it a menu item, but it's on our to-do list. Our general suggestion is to use the Modules Anywhere extension to load the SCLogin inside of the Joomla Menu item. You can see pretty simple steps on how to do that here

-Melissa

As Melissa noted, there's multiple places you could add that. For this, I'd recommend adding it to the custom.css file for your template, or whatever other customization file your template uses. Each template is different, so I can't be specific on where it would go.

The other option would be to create a custom Theme for the SCLogin module. You can read more on how to do that in the SCLogin Theme Guide . The issue with that is that it's more complex and future changes to the SCLogin module would need to be incorporated into your theme, which could be cumbersome or errorprone later.

I hope that helps get you going, but if you need any more assistance, just let us know.

Thanks,
Alex