Absolute positioning and overlapping divs

after i include the position:absolute in one of my divs, i am noticed that (the div) is being overlap by another div.

here's my fiddle,

the div that im talking about is the #nav-holder being overlapped by my footer or the black part of the fiddle.

i also used meadi query in my css.

#nav-holder { 
    position: absolute; 
    top: 0; 
    right: 0; 
    width: 200px;
}

http://ift.tt/1vR2bcd