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<h2>Responsive Sidebar Example</h2>
<p>This example use media queries to transform the sidebar to a top navigation bar when the screen size is 700px or less.</p>
<p>We have also added a media query for screens that are 400px or less, which will vertically stack and center the navigation links.</p>
<h3>Resize the browser window to see the effect.</h3>
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