Set width of fixed positioned div relative to his parent having max-width

Question

Is there any solution without JS?

html

css

Answer 1

A position:fixed element is not relative to its parent anymore. It respects only the viewport's boudaries.

MDN Definition:

fixed
Do not leave space for the element. Instead, position it at a specified position relative to the screen's viewport and don't move it when scrolled.

So any width, max-width, or whatever property will not be respected by the fixed element.

EDIT

In fact, it won't inherit the width because there's no width property defined on the wrapper.. So, try setting the child as width: 100% and inherit the max-width:

http://jsfiddle.net/mx6anLuu/2/

.wrapper {
    max-width: 500px;
    border: 1px solid red;
    height: 5500px;
    position: relative;
}


.fix {
    max-width: inherit;
    width: 100%;
    height: 20px;
    position:fixed;
    background: black;
}