<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
<body>
<div class="w3-container">
<h2>Hover Effect</h2>
<p>You can also add special effects on hover/mouse-over.</p>
<p><strong>Note:</strong> The w3-hover-sepia and w3-hover-grayscale classes are not supported in IE 11 and earlier versions.</p>
<p>w3-hover-opacity:</p>
<img src="img_snow_wide.jpg" class="w3-hover-opacity" style="width:300px">
<p>w3-hover-grayscale:</p>
<img src="img_snow_wide.jpg" class="w3-hover-grayscale" style="width:300px">
<p>w3-hover-sepia:</p>
<img src="img_snow_wide.jpg" class="w3-hover-sepia" style="width:300px">
<div class="w3-panel w3-red w3-hover-opacity">
<p>w3-hover-opacity</p>
</div>
<div class="w3-panel w3-red w3-hover-grayscale">
<p>w3-hover-grayscale</p>
</div>
<div class="w3-panel w3-red w3-hover-sepia">
<p>w3-hover-sepia</p>
</div>
</div>
</body>
</html>