How can I create a div with no margin for a header that spans across the page? Here is what I have tried:
<!DOCTYPE html>
<html>
<head>
<title></title>
<style>
.test {
height: 100px;
margin: 0;
background-color: #000000;
}
</style>
</head>
<body>
<div class="test"> </div>
</body>
</html>
However, the div still displays a margin around it. Can you please help me understand what I might be doing wrong? Thank you!