Fixed position Navigation manu

this is a starting point. Place it inside child theme’s style.css section 12.2

https://pastebin.com/iD1Y1U9G

Dear thomas,

I hope i did it correct but not working

this is how i made the ammendmnt

/* 12.2 Minimum width of 960 pixels */
@media screen and (min-width: 960px) {
.main-navigation {
position: fixed;
top: 0px;
left: 0px;
width: 100%;
height: 45px;
display: block;
margin-top: 0;
background: none repeat scroll 0% 0% rgb(255, 255, 255);
border-bottom: 5px solid rgb(255, 255, 0);
clear: both;
z-index: 300;
box-shadow: 0px 0px 18px rgba(0, 0, 0, 0.4);
}