With the F12 tools, I see that the color picker container has the sp-container
class. In spectrum.css, the style defined for that class shows the following z-index
property:
.sp-container {
...
z-index: 9999994;
}
If you set z-index: 9999995
(or more) for the fixed header, the color picker box will not overlap it.
$("#inputColor").spectrum({
color: "#f00"
});
#divHeader
{
position: fixed;
top: 0px;
left: 0px;
width: 100%;
color: #CCC;
background: #333;
padding: 8px;
z-index: 9999995;
}
#divContainer
{
margin-top: 40px;
width: 300px;
height: 1200px;
background-color: #E0E0E0;
border: solid 1px black;
}
<link href="https://cdnjs.cloudflare.com/ajax/libs/spectrum/1.8.0/spectrum.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/spectrum/1.8.0/spectrum.min.js"></script>
<div id="divHeader">Fixed header</div>
<div id="divContainer">
<input id="inputColor" type="text" />
</div>