Check out example codes for "header html css". It will help you in understanding the concepts better.

Code Example 1

<!-- Answer to: "header html css" -->

<div class="header">
  <h1>Header</h1>
  <p>My supercool header</p>
</div>

<div class="content">
  <h1>Content</h1>
  <p>Some content blablabla, some content blablabla.</p>
  <p>Some content blablabla, some content blablabla.</p>
  <p>Some content blablabla, some content blablabla.</p>
</div>

<style>
/* Style the body */
body {
  font-family: Arial;
  margin: 0;
}

/* Header/Logo Title */
.header {
  padding: 60px;
  text-align: center;
  background: #1abc9c;
  color: white;
  font-size: 30px;
}

/* Page Content */
.content {padding:20px;}
</style>

Code Example 2

<html> 
  <head>
  </head>
  <body>
    <h1>Hello World</h1>
  </body>
</html>

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