HTML
<div class="cont-search">

        <input type="text" class="in-search" placeholder="本站搜索" />         <input type="button" class="in-btn" value="" />

</div>

CSS
.cont-logo{

 float: left;

}
.cont-search{float: right; background: red;}
.in-search{

height:29px; width: 365px;

float: right;

}
.in-btn{

 height: 35px;  width: 66px;  background-image: url(images/1_07.jpg); float: right;  border: none;

}