[css] CSS-moving text from left to right

I want to create an animated HTML "marquee" that scrolls back and forth on a website:

<div class="marquee">This is a marquee!</div>

and the CSS:

.marquee {
    position: absolute;
    white-space: nowrap;
    -webkit-animation: rightThenLeft 4s linear;
}

@-webkit-keyframes rightThenLeft {
    0%   {left: 0%;}
    50%  {left: 100%;}
    100% {left: 0%;}
}

The problem is, the marquee doesn't stop when it reaches the right-hand edge of the screen; it moves all the way off the screen (making a horizontal scroll bar appear, briefly) and then comes back.

So, how do I make the marquee stop when its right-hand edge reaches the right-hand edge of the screen?

EDIT: Oddly, this does not work:

50% {right: 0%}

Hi you can achieve your result with use of <marquee behavior="alternate"></marquee>

HTML

<div class="wrapper">
<marquee behavior="alternate"><span class="marquee">This is a marquee!</span></marquee>
</div>

CSS

.wrapper{
    max-width: 400px;
    background: green;
    height: 40px;
    text-align: right;
}

.marquee {
    background: red;
    white-space: nowrap;
    -webkit-animation: rightThenLeft 4s linear;
}

see the demo:- http://jsfiddle.net/gXdMc/6/

I like using the following to prevent things being outside my div elements. It helps with CSS rollovers too.

.marquee{
    overflow:hidden;
}

this will hide anything that moves/is outside of the div which will prevent the browser expanding and causing a scroll bar to appear.

If I understand you question correctly, you could create a wrapper around your marquee and then assign a width (or max-width) to the wrapping element. For example:

<div id="marquee-wrapper">
    <div class="marquee">This is a marquee!</div>   
</div>

And then #marquee-wrapper { width: x }.

You could simply use CSS animated text generator. There are pre-created templates already

I am not sure if this is the correct solution but I have achieved this by redefining .marquee class just after animation CSS.

Check below:

<style>
#marquee-wrapper{
    width:700px;
    display:block;
    border:1px solid red;
}

div.marquee{
width:100px;
height:100px;
background:red;
position:relative;
animation:myfirst 5s;
-moz-animation:myfirst 5s; /* Firefox */
}

@-moz-keyframes myfirst /* Firefox */{
0%   {background:red; left:0px; top:0px;}
100% {background:red; left:100%; top:0px}
}
div.marquee{ 
left:700px; top:0px
}
</style>

<!-- HTMl COde -->

<p><b>Note:</b> This example does not work in Internet Explorer and Opera.</p>
<div id="marquee-wrapper">
<div class="marquee"></div>