Full Width Block in CSS
To make a fixed block take up the entire width of the screen, you need to set its width to 100%:
<div id="elem"></div>
<div id="content">
some long text
</div>
#elem {
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100px;
border: 1px solid green;
}
#content {
margin: 0 auto;
width: 300px;
text-align: justify;
font: 16px Arial;
}
:
