通过外部使用absolute进行定位
<style>
.a
{
1148px;
height:60px;
border:1px solid black;
left:100px;
top:10px;
position:absolute;}
.b
{
80px;
height:550px;
border:1px solid black;
float:left;
position:fixed;}
.c
{
80px;
height:400px;
border:1px solid black;
left:1260px;
top:100px;
position:fixed;}
.d
{
1148px;
height:110px;
border:1px solid black;
left:100px;
top:80px;
position:absolute;}
.e
{
250px;
height:130px;
border:1px solid black;
left:100px;
top:200px;
position:absolute;}
.f
{
250px;
height:180px;
border:1px solid black;
left:100px;
top:340px;
position:absolute;}
.g
{
250px;
height:230px;
border:1px solid black;
left:100px;
top:530px;
position:absolute;}
.h
{
250px;
height:230px;
border:1px solid black;
left:100px;
top:760px;
position:absolute;}
.i
{
250px;
height:210px;
border:1px solid black;
left:100px;
top:990px;
position:absolute;}
.j
{
250px;
height:210px;
border:1px solid black;
left:100px;
top:1200px;
position:absolute;}
.k
{
250px;
height:210px;
border:1px solid black;
left:100px;
top:1410px;
position:absolute;}
.l
{
250px;
height:120px;
border:1px solid black;
left:100px;
top:1630px;
position:absolute;}
.m
{
887px;
height: 40px;
border: 1px solid black;
left: 261px;
position: absolute;
}
.n
{
887px;
height:250px;
border:1px solid black;
left:260px;
top:50px;
position:absolute;}
.o
{
887px;
height:20px;
border:1px solid black;
left:260px;
top:310px;
position:absolute;}
.p
{
887px;
height:125px;
border:1px solid black;
left:260px;
top:20px;
position:absolute;}
.q
{
887px;
height:270px;
border:1px solid black;
left:260px;
top:145px;
position:absolute;}
.r
{
887px;
height:250px;
border:1px solid black;
left:260px;
top:415px;
position:absolute;}
.s
{
887px;
height:250px;
border:1px solid black;
left:260px;
top:435px;
position:absolute;}
.t
{
887px;
height:250px;
border:1px solid black;
left:260px;
top:455px;
position:absolute;}
.u
{
887px;
height:44px;
border:1px solid black;
left:260px;
top:75px;
position:absolute;}
</style>
</head>
<body>
<div class="b">b</div>
<div class="c">c</div>
<div class="a">a</div>
<div class="d">d</div>
<div class="e">e<div class="m">m</div><div class="n">n</div><div class="o">o</div></div>
<div class="f">f</div>
<div class="g">g<div class="p">p</div><div class="q">q</div><div class="r">r</div></div></div></div>
<div class="h">h<div class="s">s</div></div>
<div class="i">i<div class="t">t</div></div>
<div class="j">j</div>
<div class="k">k</div>
<div class="l">l<div class="u">u</div></div>