<div class="controls"> 
  <label for="dir">dir:</label>
  <select id="dir">
    <option value="ltr">ltr</option>
    <option value="rtl">rtl</option>
  </select>
  
  <label for="direction">direction:</label>
  <select id="direction">
    <option value="ltr">ltr</option>
    <option value="rtl">rtl</option>
  </select>

  <label for="writingmode">writing-mode:</label>
  <select id="writingmode">
    <option value="horizontal-tb">horizontal-tb</option>
    <option value="vertical-lr">vertical-lr</option>
    <option value="vertical-rl">vertical-rl</option>
  </select>
</div>

<div id="wrapper" dir="ltr" style="direction: ltr">
  <div class="block text-align">
    <h3>文本对齐(text-align)</h3>
    <p class="left">我是一行文本，使用text-align: left 左对齐, 使用text-align:right右对齐( 本行设置text-align: left)</p>
    <p class="right">我是一行文本，使用text-align: left 左对齐, 使用text-align:right右对齐( 本行设置text-align: left)</p>
  </div>
  
  <div class="block float">
    <h3>浮动布局(float)</h3>
    <div class="media">
      <div class="media__object">
        <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/182774/blueberry-cheesecake.jpg" alt="" />
      </div>
      <div class="media__body">
        <h4 class="media_heading">我是一个标题</h4>
        <p>我是一个段落，用来描述，采用了float: left布局</p>
      </div>
    </div>
    
    <div class="media media__right">
      <div class="media__object">
        <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/182774/blueberry-cheesecake.jpg" alt="" />
      </div>
      <div class="media__body">
        <h4 class="media_heading">我是一个标题</h4>
        <p>我是一个段落，用来描述，采用了float: right布局</p>
      </div>
    </div>
  </div>
  
  <div class="block">
    <h3>Flexbox布局</h3>
    <div class="flex">
      <div class="aside">Sidebar</div>
      <div class="main">Main</div>
    </div>
  </div>
  
  <div class="block">
    <h3>Grid布局</h3>
    <div class="grid">
      <div class="aside">Sidebar</div>
      <div class="main">Main</div>
    </div>
  </div>
  
  <div class="block">
    <h3>Box Alignment</h3>
    <div class="box-alignment">
      <div class="item">1</div>
      <div class="item">2</div>
      <div class="item">3</div>
    </div>
  </div>
  
  <div class="block">
    <h3>Shape</h3>
    <div class="shape">
      <img  src="https://www.footyrenders.com/render/Neymar-45.png" alt="Rabbit" />
  <p>
    Alice is feeling bored and drowsy while sitting on the riverbank with her elder sister. She then notices a talking, clothed White Rabbit with a pocket watch run past. She follows it down a rabbit hole when suddenly she falls a long way to a curious hall
    with many locked doors of all sizes.</p> 
  
  <p>She finds a small key to a door too small for her to fit through, but through it she sees an attractive garden. She then discovers a bottle on a table labelled "DRINK ME," the contents of which cause her to shrink
    too small to reach the key which she has left on the table.</p> 
  
  <p>She eats a cake with "EAT ME" written on it in currants as the chapter closes. Alice is feeling bored and drowsy while sitting on the riverbank with her elder sister. She then notices a talking,
    clothed White Rabbit with a pocket watch run past.</p> 
  <p>She follows it down a rabbit hole when suddenly she falls a long way to a curious hall with many locked doors of all sizes.</p> 
      <p>She eats a cake with "EAT ME" written on it in currants as the chapter closes. Alice is feeling bored and drowsy while sitting on the riverbank with her elder sister. She then notices a talking,
    clothed White Rabbit with a pocket watch run past.</p> 
  <p>She follows it down a rabbit hole when suddenly she falls a long way to a curious hall with many locked doors of all sizes.</p> 
    </div>
  </div>
</div>