text-decoration: underline;  a span 等标记
或border-bottom div td th等标记

这些算不算主要代码？？.css里面的
.mtDropdownMenu {
    LEFT: -1000px;
    OVERFLOW: hidden;
    POSITION: absolute;
    TOP: -1000px;
    margin-top: 4px;
}
.mtDropdownMenu .content {
    POSITION: absolute
}
.mtDropdownMenu .items {
    BORDER-RIGHT: #999 1px solid; BORDER-TOP: #999 1px solid; Z-INDEX: 2; LEFT: 0px; BORDER-LEFT: #999 1px solid; BORDER-BOTTOM: #999 1px solid; POSITION: relative; TOP: 0px
}
.top .items {
    color: #FFFFFF;

}
.mtDropdownMenu .item {
    BORDER-RIGHT: medium none; BORDER-TOP: medium none; FONT-SIZE: 12px; BORDER-LEFT: medium none; CURSOR: hand; COLOR: #4a4b4b; BORDER-BOTTOM: medium none; TEXT-DECORATION: underline
}
.mtDropdownMenu .background {
    Z-INDEX: 1; FILTER: alpha(opacity=85); LEFT: 0px; POSITION: absolute; TOP: 0px; moz-opacity: .8
}
.mtDropdownMenu .shadowRight {
    Z-INDEX: 3; FILTER: alpha(opacity=40); WIDTH: 2px; POSITION: absolute; TOP: 3px; moz-opacity: .4
}
.mtDropdownMenu .shadowBottom {
    Z-INDEX: 1; FILTER: alpha(opacity=40); LEFT: 3px; POSITION: absolute; HEIGHT: 2px; moz-opacity: .4
}
.mtDropdownMenu .hover {
    BACKGROUND: #FFFFFF; COLOR: #FF9900; TEXT-DECORATION: underline}

[[it] 本帖最后由 恨死编程 于 2008-3-11 14:53 编辑 [/it]]