Header not showing well on Firefox, Chrome or Safari

I have the problem that the header slider is showing up good on i.e. on my PC and my tablet.

But when i use Firefox, Chrome or safari it is not showing up well, tot get rid of the blank space i have used:

.header-image {
	margin-top: -50px;
}

.hgroup-wrap {
	padding-top: 0;
	padding-bottom: 0;
}

#main-nav {
	margin-top: -500px;
}

#main-nav a {
    font-size: 16px;
    height: 50px;
    padding: 15px 10px 0 10px;
}

in the custom CSS,

Can you help me,

Greetings, BartP

#main-nav {
margin-top: -500px;
}

You have used -500px which is way more than you would actually need.

Plat around these values to get the results you were looking for.

Thanks for the fast response but that is not the problem even when i use:

#main-nav {
margin-top: 1 px;
}

i still have the same problem

Greetings,

BartP

I still see that you have

#main-nav {
margin-top: -500px;
}

Printed in website source.

Just remove all code from Custom CSS field and start clean.

Thanks,

i supose it was the history of the browser that give the problem,

i put it now on -20px

keep up the good work,

Greetings,

BartP