Step 1:Create index.html file and implement as below code in it.
<img src="../image/d1.jpg" alt="demo1" width="170" height="100"> <img src="../image/d2.jpg" alt="demo2" width="170" height="100"> <img src="../image/d3.jpg" alt="demo3" width="170" height="100">
Step 2:Implement CSS code as below to set opacity for image.
<style> body { background: #c7254e; } img { opacity: 0.5; } img:hover { opacity: 1.0; } </style>
Complete Code For Applying Opacity On Mouse Over To Image Using CSS .
<!DOCTYPE html> <html> <head> <title>How To Apply Opacity On Mouse Over To Image Using CSS</title> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script> <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css"/> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script> </head> <style> body { background: #c7254e; } img { opacity: 0.5; } img:hover { opacity: 1.0; } </style> <body> <br/><br/> <div class="container"> <br> <div class="text-center"> <h1 id="color" style="color: white;">Apply Opacity On Mouse Over To Image Using CSS</h1> </div> <br> <div class="well"> <img src="../image/d1.jpg" alt="demo1" width="170" height="100"> <img src="../image/d2.jpg" alt="demo2" width="170" height="100"> <img src="../image/d3.jpg" alt="demo3" width="170" height="100"> </div> <br> </div> </body> </html>