How to create triple div border in CSS

Problem

I want to create the following div border: enter image description here I have the green border part sorted, but not the red line along the top. Any ideas?

Code so far:

#myborder {
border: 4px solid green;
}
Problem courtesy of: alias51

Solution

use this css http://jsfiddle.net/PESHk/3

#myborder {
    box-shadow: 0 0 0 4px  green, 0 0 0 4px  green inset;
    border-top:2px solid red;
    padding:8px;
}
Solution courtesy of: Hushme

Discussion

Working on Hushme's answer: http://jsfiddle.net/PESHk/2/

#myborder {
    box-shadow: 0 0 0 4px  green, 0 0 0 4px  green inset;
    border-top: 2px solid red;
    padding: 8px;
}

And here by using ::before:

#myborder {
    box-shadow: 0px 4px 15px rgba(0,0,0,0.15);
    border: 8px solid green;
    border-top: 0;
    padding: 16px 8px 8px 8px;
    position: relative;
}

#myborder::before {
    width: 100%;
    background: red;
    height: 2px;
    border: 4px solid green;
    content: "";
    display: block;
    position: absolute;
    left: 0;
    top: 0;  
}
Discussion courtesy of: Bram Vanroy

This recipe can be found in it's original form on Stack Over Flow.