dimagimburg/header-body-footer-flex-layout.html

## header-body-footer-flex-layout.html
<!DOCTYPE html>
<html>
  <head>
    <style>
      html,body{
        height: 100%;
        margin: 0;
      }

      .wrapper{
        display: flex;
        flex-direction: column;
        height: 100%;
      }

      .header{
        background: red;
        height: 50px;
      }

      .body{
        background: blue;
        flex: 1;
      }

      .footer{
        background: green;
        height:50px;
      }
    </style>
  </head>
  <body>
    <div class="wrapper">
      <div class="header">header</div>
      <div class="body">body</div>
      <div class="footer">footer</div>
    </div>
  </body>
</html>