ページを開いた時に四方から文字が集まってきます

<center>
<br><br><br><br><br><br>
<span id="idou1"style="position:relative;top:-100;">1行目</span><br>
<span id="idou2"style="position:relative;left:-300;">2行目</span><br>
<span id="idou3"style="position:relative;left:300;">3行目</span><br>
<span id="idou4"style="position:relative;top:100;">4行目</span><br>
</center>
<script type="text/javascript"><!--
idou1_x=-100;
idou2_x=-300;
idou3_x=300;
idou4_x=100;
function move(){
idou1_x += 10;
idou2_x += 30;
idou3_x -= 30;
idou4_x -= 10;
document.getElementById("idou1").style.top=idou1_x;
document.getElementById("idou2").style.left=idou2_x;
document.getElementById("idou3").style.left=idou3_x;
document.getElementById("idou4").style.top=idou4_x;
if(idou1_x)setTimeout("move()",100);
}/*himajin.moo.jp*/
move();
// --></script>