CSS Position Particles (500)

<html>

<head>

<body>

</div>

function addSprite() {
                var sprite = document.createElement('div');
                sprite.vx = Math.random();
                sprite.vy = Math.random();
                sprite.x = Math.random() * 300;
                sprite.y = Math.random() * 300;
                sprite.theta = 0;
                sprite.omega = Math.random() * 20 - 10;
                sprite.setAttribute('class', 'sprite');
                document.getElementById('container').appendChild(sprite);

sprites.push(sprite);
                count++;
            }

for ( i = 0; i < 500; i++) {
                addSprite();
            }

var transformProperty;
            function setupBrowser() {
                if (window.requestAnimationFrame) {
                    window.requestAnimFrame = window.requestAnimationFrame;
                    transformProperty = 'transform';
                } else if (window.webkitRequestAnimationFrame) {
                    window.requestAnimFrame = window.webkitRequestAnimationFrame;
                    transformProperty = 'webkitTransform';
                } else if (window.mozRequestAnimationFrame) {
                    window.requestAnimFrame = window.mozRequestAnimationFrame;
                    transformProperty = 'MozTransform';
                } else {
                    window.requestAnimFrame = function(callback) {
                        window.setTimeout(callback, 1000 / 60);
                    };
                }
            }

var s, t, i;

function render() {

for ( i = 0, l = count; i < l; i++) {
                    s = sprites[i];

s.x += s.vx;
                    s.y += s.vy;

dx = clientX - s.x;
                    dy = clientY - s.y;

dist = Math.sqrt(dx * dx + dy * dy);

if (dist > 0) {
                        co = .3 / dist;
                        s.vx += co * dx;
                        s.vy += co * dy;
                    }

// drag
                    s.vx *= .995;
                    s.vy *= .995;

s.style.top = ~~s.y + 'px';
                    s.style.left = ~~s.x + 'px';
                }

}

var clientX = 50, clientY = 50;

document.addEventListener('mousemove', function(e) {
                clientX = e.clientX;
                clientY = e.clientY;
            });

setupBrowser();

(function animloop() {
                window.requestAnimFrame(animloop);
                render();
            })();

</script>

</body>

</html>