Change location/Size of the Menu Bar

Hi there

I know many people already asked about this. But I tried so many times but I just can’t figure out how to widen my menu bar. I want to add a new Menu point “Group Tours” but if I do this the button will be on a second line on the menu bar and not added on the left side. My website is mellowtrek.com

How do I widen the menu bar or how do I change the gap between the menu points? I tried changing style.css
.navbar .navbar-inner {
margin: 14px 20px 10px -200px;
padding-left: 5px;
max-width: 97%
}
and found this in rtl.css
#access {
float:right;
}

#access .menu-header,
div.menu {
margin-right: 12px;
margin-left: 0;

}

#access .menu-header li,
div.menu li{
float:right;
}

#access ul ul {
left:auto;
right:0;
float:right;
}
#access ul ul ul {
left:auto;
right:100%;
}

Thanks for your help!