I am trying to produce a progress bar with a divider bar that separates sections. This divider bar (child <div/>) hangs below the progress bar (parent <div/>). Thus, I want the progress bar to cover all of the divider bar except for the part that hangs below.
Here is a very simplified representation:
<html>
<head>
<style>
body {
width:500px;
margin:0 auto;
}
#parent {
width:50%;
height:30px;
background-color: yellow;
}
#child {
width:1px;
height:50px;
background-color:black;
float:right;
margin-right:100px;
}
</style>
</head>
<body>
<div id="parent">
<div id="child"></div>
</div>
</body>
</html>
How can I get the yellow part of the progress bar to cover up the intersecting portion of the divider bar?
Here is an image representing what I’m looking for:

Thanks in advance!
Setting a parent to position: relative will allow you to absolutely position the marker. Since they’d both then be appropriate types for z-index, I would take that route. Here’s a jsfiddle:
http://jsfiddle.net/WXDZF/
Seems to be the cleanest solution. In this case you really are trying to position something, not push something up or down, so I would recommend staying away from using a margin in an inorganic way.