面板消失在垂直滚动条后面

Question

我有一个面板，它在滚动条后面消失，见截图

这是CSS

    #menu {
    list-style:none;
    width:350px;
    height:30px;
    padding:0px 10px 0px 10px;
    margin-top: 10px;
}

#menu li {
    float:left;
    display:block;
    text-align:center;
    position:relative;
    padding: 4px 10px 4px 10px;
    margin-right:30px;
    margin-top:7px;
    border:none;
}

#menu li:hover {
    border: 1px solid #777777;
    padding: 4px 9px 4px 9px;

    /* Background color and gradients */

    background: #F4F4F4;
    background: -moz-linear-gradient(top, #F4F4F4, #EEEEEE);
    background: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#F4F4F4), to(#EEEEEE));

    /* Rounded corners */

    -moz-border-radius: 5px 5px 0px 0px;
    -webkit-border-radius: 5px 5px 0px 0px;
    border-radius: 5px 5px 0px 0px;
}

#menu li a {
    font-family:Arial, Helvetica, sans-serif;
    font-size:14px; 
    color: #EEEEEE;
    display:block;
    outline:0;
    text-decoration:none;
    text-shadow: 1px 1px 1px #000;
}

#menu li:hover a {
    color:#161616;
    text-shadow: 1px 1px 1px #ffffff;
}
#menu li .drop {
    padding-right:21px;
    background:url("../images/arrow.gif") no-repeat right 8px;
}
#menu li:hover .drop {
    background:url("../images/arrow.gif") no-repeat right 7px;
}

.dropdown_1column, 
.dropdown_2columns, 
.dropdown_3columns, 
.dropdown_4columns,
.dropdown_5columns {
    margin:4px auto;
    float:left;
    position:absolute;
    left:-999em; /* Hides the drop down */
    z-index: 9999;
    text-align:left;
    padding:10px 5px 10px 5px;
    border:1px solid #777777;
    border-top:none;

    /* Gradient background */
    background:#F4F4F4;
    background: -moz-linear-gradient(top, #EEEEEE, #BBBBBB);
    background: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#EEEEEE), to(#BBBBBB));

    /* Rounded Corners */
    -moz-border-radius: 0px 5px 5px 5px;
    -webkit-border-radius: 0px 5px 5px 5px;
    border-radius: 0px 5px 5px 5px;
}


.dropdown_2columns {width: 450px; min-height: 300px;}


#menu li:hover .dropdown_1column, 
#menu li:hover .dropdown_2columns, 
#menu li:hover .dropdown_3columns,
#menu li:hover .dropdown_4columns,
#menu li:hover .dropdown_5columns {
    left:-1px;
    top:auto;
}

.col_1,
.col_2,
.col_3,
.col_4,
.col_5 {
    display:inline;
    float: left;
    position: relative;
    margin-left: 5px;
    margin-right: 5px;
}
.col_1 {width:130px;}
.col_2 {width:270px;}
.col_3 {width:410px;}
.col_4 {width:550px;}
.col_5 {width:690px;}

#menu .menu_right {
    float:right;
    margin-right:0px;
}
#menu li .align_right {
    /* Rounded Corners */
    -moz-border-radius: 5px 0px 5px 5px;
    -webkit-border-radius: 5px 0px 5px 5px;
    border-radius: 5px 0px 5px 5px;
}

#menu li:hover .align_right {
    left:auto;
    right:-1px;
    top:auto;
}

#menu li:hover div a {
    font-size:12px;
    color:#015b86;
}
#menu li:hover div a:hover {
    color:#029feb;
}

和html

    <ul id="menu">

    <li><a href="index.php/extensions" class="drop">Extensions</a>

        <div class="dropdown_2columns">



        </div>

    </li>

    <li><a href="index.php/forum/index" class="drop">Forum</a>

        <div class="dropdown_2columns">



        </div>

    </li>   

    <li><a href="#" class="drop">Blog</a>

        <div class="dropdown_2columns">



        </div>

    </li>

</ul>

我怎样才能防止这种情况发生变化？我能以某种方式从右到左显示面板吗？

为奇怪的标题和描述道歉，这次我真的不知道如何更好地解释自己。

请提供帮助，

提前致谢

Answer 1

decided to go with this one

看起来很好并且运作良好