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  <h2>Grayscale Effect</h2>
  <p>The w3-grayscale classes add a grayscale effect to an element.</p>

<p>Normal:</p>
  <img src="img_snow_wide.jpg" alt="Snow" style="width:300px">
  <p>w3-grayscale-min:</p>
  <img src="img_snow_wide.jpg" alt="Snow" class="w3-grayscale-min" style="width:300px">
  <p>w3-grayscale:</p>
  <img src="img_snow_wide.jpg" alt="Snow" class="w3-grayscale" style="width:300px">
  <p>w3-grayscale-max (black and white):</p>
  <img src="img_snow_wide.jpg" alt="Snow" class="w3-grayscale-max" style="width:300px">

<div class="w3-panel w3-red w3-grayscale">
    <p>Red with grayscale</p>
  </div>
  <div class="w3-panel w3-blue w3-grayscale">
    <p>Blue with grayscale</p>
  </div>
  <div class="w3-panel w3-green w3-grayscale">
    <p>Green with grayscale</p>
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