html – 只滚动内容div,其他应该是固定的

我有三个div我需要标题和left_side div来修复和内容div滚动.我一直在寻找解决方案,发现有溢出和位置的东西.但我不能使用它的核心.我该怎么做？我会感谢各种答案.

HTML
------
<div id="header">

</div>

<div id="left_side">    
</div>

<div id="content">
</div


CSS
-----
body {   
    width: 100%;
    height: auto;
    padding: 0;
    margin: 0px auto;
    font-family: Calibri,Georgia,Ubuntu-C;  
    font-size: 16px;
    margin-bottom: 20PX
}

#header{
    width: 100%;
    height: 139px;
    background-image: url('images/Header_grey.gif');   
}


#left_side{
    width: 210px;
    height: 700px;
    background-image: url('images/Left_side.gif');
    background-repeat:repeat-y;
    overflow:hidden; 
    position:absolute;
    font-size: 16px;
}

#content{
     height: auto;
     padding: 20px;
     margin-left: 230px;
     margin-right: 20px;
    padding-bottom: 30px
 }

解决方法

溢出：自动;需要时添加滚动条

#header{
    width: 100%;
    height: 139px;
    background-image: url('images/Header_grey.gif');   
    overflow: hidden;  //code added to prevent scroll
}


#left_side{
    width: 210px;
    height: 700px;
    background-image: url('images/Left_side.gif');
    background-repeat:repeat-y;
    overflow:hidden;  //code added to prevent scroll
    position:absolute;
    font-size: 16px;
}
#content{
     height: auto;
     padding: 20px;
     margin-left: 230px;
     margin-right: 20px;
    padding-bottom: 30px;
    overflow: auto;  //code added
 }