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<h2>Show a Block</h2>
<p>The <b>w3-show</b> class displays an element as a block.</p>
<p>Click the button to show or hide the message.</p>
<p>Notice how the following paragraph moves when the message appears.</p>

<div id="message" class="w3-panel w3-pale-blue w3-hide">
  <p>This message is now visible.</p>
</div>
<p>This paragraph follows the message.</p>

<p>The <b>w3-hide</b> class hides the message initially. JavaScript adds or removes 
<b>w3-show</b> when you click the button.</p>

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