Fixed Header with social Icons and… Transparent

Hi,

i tired sereval things i found in other threats but i did not work. I want the header transparent. The logo should be visible.

http://holidaymarketing.de/

This is the code i use now:

strong.logo { left: 39%; }
#header_main { padding-bottom: 34px; }
.fixed_header.social_header #main { padding-top: 181px; }
.current-menu-item>a>.avia-menu-fx { display: none;}
nav.main_menu { position: absolute; right: 20%; top: 70%; }
li:hover .avia-menu-fx { display: none; }
.main_menu .menu ul { margin-top: 2px; }

These did not work:

#header_main { border-bottom-style: none; }
#header_main_alternate { background-color: white; }

…

.header_color .header_bg, .header_color{
background-color: transparent;
}

Another thing is the submenu is displayed.

Thank you very much in advance!!

Regards