if you visit site , you can see page loading time is too much.I am using the below code to display single image, we are using same kind of code for all 16 images, please review code and guide me to improve performance..links1234 { color : #908983;}.links1234:hover { color : #f85700;}.grow {  height: auto;  padding: 5px 5px 5px 10px;  border-radius: 10px;  width: 23%;  margin: 5px 1% 5px 1%;  float: left;  position: relative;  transition: height 0.5s;  -webkit-transition: height 0.5s;  text-align: center;  background-color : #fff;}.grow:hover ul{  display: block;}.grow:hover {  box-shadow: 0px 0px 5px 1px rgba(0,0,0,.25);}.grow ul {  margin-top: -3px;  padding: 5px;  padding-top:10px;  border-radius:0px 0px 10px 10px;  list-style: none;  display: none;  position: absolute;  z-index: 1;  background: #fff;  box-shadow: 0 5px 5px 1px rgba(0,0,0,.25);  left: 0;  right: 0;}.grow img{  width: 100%;}.expand {    position:relative;    right:8px;    top:4px;}<div class=grow>  <img class = expand src=http://sbdev2.kidsdial.com:81/media/cases/apple.png  onmouseover=this.src='http://sbdev2.kidsdial.com:81/media/cases/apple_active.png'onmouseout=this.src='http://sbdev2.kidsdial.com:81/media/cases/apple.png'border=0 alt=apple/>  <ul><li><a class=links1234 href=/cases-covers/apple-iphone-4.html>iPhone 4</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-4s.html>iPhone 4s</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-5.html>iPhone 5</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-5c.html>iPhone 5C</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-5s.html>iPhone 5S</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-6.html>iPhone 6</a></li><li><a class=links1234 href=/cases-covers/apple-iphone-6-plus.html>iPhone 6 Plus</a></li>  </ul></div>
Load images embedded in DOM events performantly
javascript;performance;html;css