How can I change the height of the header to put a higher logo on the DW ARGO theme?

Hi Manuel !  
To change the height of the header on the DW ARGO theme, please go to Dashboard >> Appearance >> Customize >> Custom Codes tab, add the following code to the “Header Code”

<style>
 .navbar .brand {
   height: ...px;
   width: ....px;
}
.navbar .nav > li {
   height: ...px;
}
</style>

Hope that helps!