This is usually due to missing CSS rules that occur if you customize the assembly. For example, here is my custom assembly page where I didn’t take tabs into account.

Then I copied the rules from the full download and tested it in a browser. What you can also do to make sure this is your problem.
.tabs { *zoom: 1; margin-bottom: 0 !important; } .tabs:before, .tabs:after { content: " "; display: table; } .tabs:after { clear: both; } .tabs dd { position: relative; margin-bottom: 0 !important; top: 1px; float: left; } .tabs dd > a { display: block; background:
Paste verification code

You can then go over or add the code manually or simply replace the css files for the foundation.
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