Bootstrap is a back-end framework which is developed by Twitter. It has a grid system for make responsive web design.
This system divides 12 part to page. In this way we can design web pages with mobile first principle.
There are classes for every screen size:
Extra small devices (for smaller than 768 px screens, phones) : .col-xs-
Small devices Tablets (for bigger than 768 px, tablets) : .col-sm-
Medium devices (for bigger than 992 px, desktops) : .col-md-
Large devices (for bigger than 1200 px, desktops) : .col-lg-
Example Code:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container-fluid">
<h1>Hello World!</h1>
<p>Resize the browser window to see the effect.</p>
<div class="row">
<div class="col-xs-7 col-sm-6 col-lg-8" style="background-color:red;">.col-xs-7 .col-sm-6 .col-lg-8</div>
<div class="col-xs-5 col-sm-6 col-lg-4" style="background-color:lavender;">.col-xs-5 .col-sm-6 .col-lg-4</div>
</div>
<div class="row">
<div class="col-xs-6 col-sm-8 col-lg-10" style="background-color:lavenderblush;">.col-xs-6 .col-sm-8 .col-lg-10</div>
<div class="col-xs-6 col-sm-4 col-lg-2" style="background-color:lightgrey;">.col-xs-6 .col-sm-4 .col-lg-2</div>
</div>
<div class="row" style="background-color:lightcyan;">
<div class="col-xs-6">.col-xs-6</div>
<div class="col-xs-6">.col-xs-6</div>
</div>
</div>
</body>
</html>
i admired your eng 😀
Woow. That is awesome.