两个层，分列左右。 以下是相关代码，都是DW生成的：

<style>
<!--
.lrimg{
margin-top: 100px
}
#LayerLeft {
position:absolute;
width:120px;
height:400px;
z-index:1;
}
#LayerRight {
position:absolute;
width:120px;
height:400px;
z-index:2;
}
-->
</style>
<script type="text/JavaScript">
<!--
function MM_findObj(n, d) { //v4.01
var p,i,x; if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function flevDivPositionValue(sDiv, sProperty) { // v2.1, Marja Ribbers-de Vroed, FlevOOware
this.opera = (window.opera); // Opera 5+
this.ns4 = (document.layers); // Netscape 4.x
this.ns6 = (document.getElementById && !document.all && !this.opera); // Netscape 6+
this.ie = (document.all); // Internet Explorer 4+
var sValue = ""; docObj = eval("MM_findObj('" + sDiv + "')"); if (docObj == null) {return 0;}
if ((sProperty == "left") || (sProperty == "top")) {
if (!this.ns4) {docObj = docObj.style;}
sValue = eval("docObj." + sProperty);
if ((this.ie) && (sValue == "")) { // IE (on PC) bug with nested layers
if (sProperty == "top") { sValue = eval(sDiv + ".offsetTop"); }
else { sValue = eval(sDiv + ".offsetLeft"); }
};
}
else {
if (this.opera) {
docObj = docObj.style;
if (sProperty == "height") { sValue = docObj.pixelHeight; }
else if (sProperty == "width") { sValue = docObj.pixelWidth; }
}
else if (this.ns4) {sValue = eval("docObj.clip." + sProperty);}
else if (this.ns6) {sValue = document.defaultView.getComputedStyle(docObj, "").getPropertyValue(sProperty); }
else if (this.ie) {
if (sProperty == "width") { sValue = eval(sDiv + ".offsetWidth"); }
else if (sProperty == "height") { sValue = eval(sDiv + ".offsetHeight"); }
}
}
sValue = (sValue == "") ? 0 : sValue;
if (isNaN(sValue)) { if (sValue.indexOf('px') > 0) { sValue = sValue.substring(0,sValue.indexOf('px')); } }
return parseInt(sValue);
}

function flevPersistentLayer() { // v3.3, Marja Ribbers-de Vroed, FlevOOware
var sD = arguments[0], oD = eval("MM_findObj('" + sD + "')"), iWW, iWH, iSX, iSY, iT = 10, sS = "";
if (!document.layers) {oD = oD.style;}
if (oD.tmpTimeout != null) {clearTimeout(oD.tmpTimeout);}
var sXL = arguments[1], sXC = arguments[2], sXR = arguments[3], sYT = arguments[4], sYC = arguments[5], sYB = arguments[6];
var iS = (arguments.length > 7) ? parseInt(arguments[7]) : 0, iPx = (arguments.length > 8) ? parseInt(arguments[8]) : 0;
if (window.innerWidth) { // NS4, NS6 and Opera
var oW = window; iWW = oW.innerWidth; iWH = oW.innerHeight; iSX = oW.pageXOffset; iSY = oW.pageYOffset; }
else if (document.documentElement && document.documentElement.clientWidth) { // IE6 in standards compliant mode
var oDE = document.documentElement; iWW = oDE.clientWidth; iWH = oDE.clientHeight; iSX = oDE.scrollLeft; iSY = oDE.scrollTop; }
else if (document.body) { // IE4+
var oDB = document.body; iWW = oDB.clientWidth; iWH = oDB.clientHeight; iSX = oDB.scrollLeft; iSY = oDB.scrollTop; }
else {return;}
var iCX = iNX = flevDivPositionValue(sD, 'left'), iCY = iNY = flevDivPositionValue(sD, 'top');
if (sXL != "") {iNX = iSX + parseInt(sXL);}
else if (sXC != "") {iNX = Math.round(iSX + (iWW/2) - (flevDivPositionValue(sD, 'width')/2));}
else if (sXR != "") {iNX = iSX + iWW - (flevDivPositionValue(sD, 'width') + parseInt(sXR));}
if (sYT != "") {iNY = iSY + parseInt(sYT);}
else if (sYC != "") {iNY = Math.round(iSY + (iWH/2) - (flevDivPositionValue(sD, 'height')/2));}
else if (sYB != "") {iNY = iSY + (iWH - flevDivPositionValue(sD, 'height') - parseInt(sYB));}
if ((iCX != iNX) || (iCY != iNY)) {
if (iS > 0) {
if (iPx > 0) { iT = iS;
var iPxX = iPx, iPxY = iPx, iMX = Math.abs(iCX - iNX), iMY = Math.abs(iCY - iNY);
// take care of diagonal movement
if (iMX < iMY) {iPxY = (iMX != 0) ? ((iMY/iMX)*iPx) : iPx;}
else {iPxX = (iMY != 0) ? ((iMX/iMY)*iPx) : iPx;}
if (iPxX >= iMX) {iPxX = Math.min(Math.ceil(iPxX), iPx);}
if (iPxY >= iMY) {iPxY = Math.min(Math.ceil(iPxY), iPx);}
// temporary X/Y coordinates
if ((iCX < iNX) && (iCX + iPxX < iNX)) {iNX = iCX + iPxX;}
if ((iCX > iNX) && (iCX - iPxX > iNX)) {iNX = iCX - iPxX;}
if ((iCY < iNY) && (iCY + iPxY < iNY)) {iNY = iCY + iPxY;}
if ((iCY > iNY) && (iCY - iPxY > iNY)) {iNY = iCY - iPxY;} }
else {
var iMX = ((iNX - iCX) / iS), iMY = ((iNY - iCY) / iS);
iMX = (iMX > 0) ? Math.ceil(iMX) : Math.floor(iMX); iNX = iCX + iMX;
iMY = (iMY > 0) ? Math.ceil(iMY) : Math.floor(iMY); iNY = iCY + iMY; } }
if ((parseInt(navigator.appVersion)>4 || navigator.userAgent.indexOf("MSIE")>-1) && (!window.opera)) {sS="px";}
if (iMX != 0) {eval("oD.left = '" + iNX + sS + "'");}
if (iMY != 0) {eval("oD.top = '" + iNY + sS + "'");} }
var sF = "flevPersistentLayer('" + sD + "','" + sXL + "','" + sXC + "','" + sXR + "','" + sYT + "','" + sYC + "','" + sYB + "'," + iS + "," + iPx + ")";
oD.tmpTimeout = setTimeout(sF,10);
}

function flevInitPersistentLayer() { // v3.3, Marja Ribbers-de Vroed, FlevOOware
if (arguments.length < 8) {return;}
var sD = arguments[0]; if (sD == "") {return;}
var oD = eval("MM_findObj('" + sD + "')"); if (!oD) {return;}
var iCSS = parseInt(arguments[1]);
var sXL = arguments[2], sXC = arguments[3], sXR = arguments[4], sYT = arguments[5], sYC = arguments[6], sYB = arguments[7];
var iS = (arguments.length > 8) ? parseInt(arguments[8]) : 0, iPx = (arguments.length > 9) ? parseInt(arguments[9]) : 0;
if (iCSS != 0) { if (!document.layers) {oD = oD.style;} sXL = parseInt(oD.left), sYT = parseInt(oD.top);}
var sF = "flevPersistentLayer('" + sD + "','" + sXL + "','" + sXC + "','" + sXR + "','" + sYT + "','" + sYC + "','" + sYB + "'," + iS + "," + iPx + ")";
eval(sF);
}
//-->
</script>
</head>

<body onLoad="flevInitPersistentLayer('LayerLeft',0,'0','','','0','','',10);flevInitPersistentLayer('LayerRight',0,'','','0','0','','',10)">
<div id="LayerLeft" align="right"><img class="lrimg" src="pic/dl1.gif" width=90 height=360> </img></div>
<div id="LayerRight" align="left"><img class="lrimg" src="pic/dl2.gif" width=90 height=360> </img></div>