Hi marco17
I found some errors in the settings for your theme in template.css at line 4118 i corrected some of them
example :
This is the correct code for the 1680 resolution
@media (min-width: 1680px) {
div.t3-wrapper.menu-vertical {
padding-left: 240px;
max-width: 100%;
margin-left: 0;
width: 1920px;
It was set before to width: 1290px;
evidently there was a mispelled number
Please have a look at it now
My suggestion is to remove any thememagic customization and start with default layouts and use the variables.less file to change colors of the website and then compile less to css
Hope it helps
Regards