以下是部分CSS代碼：

.nav{
?? ?height:40px;clear: both; }
.nav_left{
?? ?width:10px;
?? ?background:url(../images/nav_left.jpg) no-repeat;
}
.nav_mid{
?? ?width:980px;
?? ?background:url(../images/nav_bg.jpg) repeat-x;
}
.nav_right{
?? ?width:10px;
?? ?background:url(../images/nav_right.jpg) no-repeat;
?? ?}
.nav_left,.nav_mid,.nav_right{
?? ?float:left;height:40px;}

以下是部分HTML代碼：

<div calss="nav">
? <div class="nav_left"></div>
? <div class="nav_mid">
????? <div class="nav_mid_left">
??????? <ul>
????????? <li><a href="#">首頁</a></li>
????????? <li><a href="#">關于慕課</a></li>
????????? <li><a href="#">新聞動態</a></li>
????????? <li><a href="#">課程中心</a></li>
????????? <li><a href="#">在線課程</a></li>
????????? <li><a href="#">人才招聘</a></li>
??????? </ul>
????? </div>
????? <div class="nav_mid_right">
??????? <form action="" method=""><input type="text"/></form>
????? </div>
??? <div class="nav_right"></div>
? </div>
? <div class="nav_right"></div>
</div>
</body>
</html>