hello so i have a content box and this menu box.. now the menu box moves when you have the browser in normal fullsize, and if you change size of the browser...

here is picture:

What do i do wrong?

Here is my code:

#menu {
position: absolute;
background: #FFF;
text-decoration: none;
border: 1px solid #000;
color: #000;
padding-left: 14px;
padding-right: 14px;
margin: 12px;
}

#content {
margin: auto;
width: 800px;
border: 1px solid #000;
padding: 10px;
}