Not sure where the problem is with my header bar, I'm new to HTML, I'm following a tutorial from w3schools but when I create a header bar, there's a white border around the black header, on the example they give there isn't, not sure why this happens. I've copied all the relevant bits from the tutorial.
HTML:
<!DOCTYPE html>
<html>
<head>
<title>Title</title>
<meta charset="utf-8"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<link rel="stylesheet" type="text/css" href="css/stylesheet.css"/>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"/>
</head>
<style>
html, body, h1, h2, h3, h4, h5 {font-family: "Open Sans", sans-serif}
</style>
<body>
<div class="header">
<a class="header-left" href="#">Home</a>
<div class="header-right">
<a href="#">Blog</a>
<a href="#">About</a>
<a href="#">Contact</a>
</div>
</div>
</body>
</html>
CSS:
.header {overflow:hidden;background-color:#000;padding:10px;}
.header a {color:#fff;text-align:center;text-decoration:none;font-size:20px;padding:10px;}
.header-left {float:left;}
.header-right {float:right;}
Page that's being displayed, there's a border around the black header