响应式布局设计能够极大地提升用户体验效果，在解决设备只见的差异化之外，响应式设计极有可能因为要兼容的代码多，影响了加载速度，也有可能会影响精确度判断。但优点大于缺点，我们不可否认，响应式的布局方式更流行于人们的社交和生活中。
在响应式设计中，我们的开发要考虑到移动设备，并且移动设备优先，页面要如何在多终端展示；在设备不支持新的Html属性和CSS3的某些属性的情况下，如何充分发挥硬件设备的最大功能等。
如何实现响应式布局呢？在我学习的课程中，他提到了三种。
①：CSS3-Media Query
常见的属性：device-width，device-height —— 屏幕宽高 width，height —— 渲染窗口宽高 orientation —— 设备方向 resolution —— 设备分辨率
这是最简单的方式，具体的代码如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>index1</title>
<link rel="stylesheet" type="text/css" href="css-index1.css" media="only screen and (max-width:480px)"/>
<style type="text/css">
@media screen and (min-width:480px){
body{background: blue;}
}
</style>
</head>
<body>
</body>
</html>body{background: red}②：借助原生的JavaScript，但是成本高，不推荐。
③：第三方开源框架，可以很好的支持浏览器响应式布局的设计。
我百度了很多关于响应式开发的文档，最终决定以Bootstrap作为自己和响应式开发的初次接触。
http://www.bootcss.com/这个是Bootstrap中文网。Bootstrap是一款移动优先的前端框架，可以写非常说的代码，实现多终端的页面适配，Bootstrap主要是基于jQuery进行JavaScript处理，支持LESS来做CSS的扩展。Bootstrap框架在布局、版式、控件、特效等方面都做得很好，虽然我是刚接触，但深深的为之震撼，丰富的展示效果，方便的开发真的是很棒的体验。Bootstrap的扩展插件和组件也很多，涉及显示组件、兼容性、图标库等各方面。
这个是用组件根据课程做的一个练习，还有不足之处~明天修改~嘿嘿~今天临时有点事~
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- The above 3 meta tags *must* come first in the head; any other head content must come *after* these tags -->
<meta name="description" content="">
<meta name="author" content="">
<link rel="icon" href="../../favicon.ico">
<title>Off Canvas Template for Bootstrap</title>
<!-- Bootstrap core CSS -->
<link href="../../dist/css/bootstrap.min.css" rel="stylesheet">
<!-- IE10 viewport hack for Surface/desktop Windows 8 bug -->
<link href="../../assets/css/ie10-viewport-bug-workaround.css" rel="stylesheet">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css" integrity="sha384-PsH8R72JQ3SOdhVi3uxftmaW6Vc51MKb0q5P2rRUpPvrszuE4W1povHYgTpBfshb" crossorigin="anonymous">
<!-- Custom styles for this template -->
<link href="offcanvas.css" rel="stylesheet">
<!-- Just for debugging purposes. Don't actually copy these 2 lines! -->
<!--[if lt IE 9]><script src="../../assets/js/ie8-responsive-file-warning.js"></script><![endif]-->
<script src="../../assets/js/ie-emulation-modes-warning.js"></script>
<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/html5shiv/3.7.3/html5shiv.min.js"></script>
<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
</head>
<body>
<nav class="navbar navbar-fixed-top navbar-inverse">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">Project name</a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Home</a></li>
<li><a href="#about">About</a></li>
<li><a href="#contact">Contact</a></li>
</ul>
</div><!-- /.nav-collapse -->
</div><!-- /.container -->
</nav><!-- /.navbar -->
<div class="container">
<div class="row row-offcanvas row-offcanvas-right">
<div class="col-xs-12 col-sm-9">
<p class="pull-right visible-xs">
<button type="button" class="btn btn-primary btn-xs" data-toggle="offcanvas">Toggle nav</button>
</p>
<div class="jumbotron">
<h1>Hello, world!</h1>
<p>This is an example to show the potential of an offcanvas layout pattern in Bootstrap. Try some responsive-range viewport sizes to see it in action.</p>
</div>
<div class="row">
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
<div class="col-xs-6 col-lg-4">
<h2>Heading</h2>
<p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
<p><a class="btn btn-default" href="#" role="button">View details »</a></p>
</div><!--/.col-xs-6.col-lg-4-->
</div><!--/row-->
</div><!--/.col-xs-12.col-sm-9-->
<div class="col-xs-6 col-sm-3 sidebar-offcanvas" id="sidebar">
<div class="list-group">
<a href="#" class="list-group-item active">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
<a href="#" class="list-group-item">Link</a>
</div>
</div><!--/.sidebar-offcanvas-->
</div><!--/row-->
<hr>
<footer>
<p>© 2016 Company, Inc.</p>
</footer>
</div><!--/.container-->
<!-- Bootstrap core JavaScript
================================================== -->
<!-- Placed at the end of the document so the pages load faster -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script>window.jQuery || document.write('<script src="../../assets/js/vendor/jquery.min.js"><\/script>')</script>
<script src="../../dist/js/bootstrap.min.js"></script>
<!-- IE10 viewport hack for Surface/desktop Windows 8 bug -->
<script src="../../assets/js/ie10-viewport-bug-workaround.js"></script>
<script src="offcanvas.js"></script>
</body>
</html>