scroll vertically

<!DOCTYPE html>
<title>Example</title>

<style>
.example3 {
 height: 200px;	
 overflow: hidden;
 position: relative;
}
.example3 h3 {
 position: absolute;
 width: 100%;
 height: 100%;
 margin: 0;
 line-height: 50px;
 text-align: center;
 /* Starting position */
 -moz-transform:translateY(-100%);
 -webkit-transform:translateY(-100%);	
 transform:translateY(-100%);
 /* Apply animation to this element */	
 -moz-animation: example3 15s linear infinite;
 -webkit-animation: example3 15s linear infinite;
 animation: example3 15s linear infinite;
}
/* Move it (define the animation) */
@-moz-keyframes example3 {
 0%   { -moz-transform: translateY(-100%); }
 100% { -moz-transform: translateY(100%); }
}
@-webkit-keyframes example3 {
 0%   { -webkit-transform: translateY(-100%); }
 100% { -webkit-transform: translateY(100%); }
}
@keyframes example3 {
 0%   { 
 -moz-transform: translateY(-100%); /* Firefox bug fix */
 -webkit-transform: translateY(-100%); /* Firefox bug fix */
 transform: translateY(-100%); 		
 }
 100% { 
 -moz-transform: translateY(100%); /* Firefox bug fix */
 -webkit-transform: translateY(100%); /* Firefox bug fix */
 transform: translateY(100%); 
 }
}
</style>

<div class="example3">
<h3>Scrolling down... </h3>
</div>