我正在尝试定位此下拉菜单。它仅适用于 Chrome，子菜单显示在悬停链接的正下方。但在 IE 和 firefox 中，它们都出现在左下角的同一个位置。
CSS
#menu {
float:right;
list-style-type: none;
padding: 0px;
margin: 36px 130px 0 0;
}
#menu a {
height:50px;
font-size:18px;
font-weight:bold;
color:black;
text-decoration:none;
}
#menu a:hover {
color:#FFF;
border:#002d56 6px solid;
background-color:#002d56;
opacity:0.8;
}
#menu li {
position:relative;
display:inline;
padding:24px 5px 10px 5px;
margin-left:40px;
}
#menu li:hover > ul
{
display: block;
}
#menu li:hover ul {
display: block;
}
#menu ul li:first-child a:after /*triangulo*/
{
content: '';
position: absolute;
left: 10px;
top: -15px;
z-index:99999;
width: 0;
height: 0;
border-left: 5px solid transparent;
border-right: 5px solid transparent;
border-bottom: 8px solid #002d56;
}
/*submenu*/
#menu ul {
padding:5px 30px 5px 10px;
margin-top:12px;
position:absolute;
display:none;
z-index: 99999;
float:left;
/*visual*/
background-color:#002d56;
box-shadow: 4px 4px 10px #999;
border:#002d56 2px solid;
/*opacity:0.9;*/
border-radius:10px;
/*gradiente*/
background-image: linear-gradient(bottom, rgb(0,72,135) 39%, rgb(0,43,84) 66%);
background-image: -o-linear-gradient(bottom, rgb(0,72,135) 39%, rgb(0,43,84) 66%);
background-image: -moz-linear-gradient(bottom, rgb(0,72,135) 39%, rgb(0,43,84) 66%);
background-image: -webkit-linear-gradient(bottom, rgb(0,72,135) 39%, rgb(0,43,84) 66%);
background-image: -ms-linear-gradient(bottom, rgb(0,72,135) 39%, rgb(0,43,84) 66%);
background-image: -webkit-gradient(
linear,
left bottom,
left top,
color-stop(0.39, rgb(0,72,135)),
color-stop(0.66, rgb(0,43,84))
);
}
#menu ul a
{
color:#FFF;
font-size:14px;
font-weight:400;
padding: 10px;
height: auto;
line-height: 1;
display: block;
white-space: nowrap;
float: none;
text-transform: none;
}
#menu ul a:hover {
background-color:transparent;
border:none;
display: block;
font-size:14px;
font-weight:400;
text-decoration:underline;
opacity:1;
}
#menu ul li
{
float: none;
margin: 0;
padding: 0;
display: block;
}
.form
{
color:#FFF;
font-size:14px;
font-weight:400;
padding: 10px;
height: auto;
line-height: 1;
display: block;
white-space: nowrap;
float: none;
text-transform: none;
}
.form li:first-child/*triangulo*/
{
content: '';
position: absolute;
left: 10px;
top: -15px;
z-index:99999;
width: 0;
height: 0;
border-left: 5px solid transparent;
border-right: 5px solid transparent;
border-bottom: 8px solid #002d56;
}
.forminput {
margin:8px 0;
width:100px;
border:2px solid #919293;
border-radius:10px;
padding:5px;
/*gradiente*/
background: rgb(255,255,255); /* Old browsers */
/* IE9 SVG, needs conditional override of 'filter' to 'none' */
background: url(data:image/svg+xml;base64,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);
background: -moz-linear-gradient(top, rgba(255,255,255,1) 0%, rgba(214,214,214,1) 70%, rgba(188,188,188,1) 89%, rgba(163,163,163,1) 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(255,255,255,1)), color-stop(70%,rgba(214,214,214,1)), color-stop(89%,rgba(188,188,188,1)), color-stop(100%,rgba(163,163,163,1))); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, rgba(255,255,255,1) 0%,rgba(214,214,214,1) 70%,rgba(188,188,188,1) 89%,rgba(163,163,163,1) 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, rgba(255,255,255,1) 0%,rgba(214,214,214,1) 70%,rgba(188,188,188,1) 89%,rgba(163,163,163,1) 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, rgba(255,255,255,1) 0%,rgba(214,214,214,1) 70%,rgba(188,188,188,1) 89%,rgba(163,163,163,1) 100%); /* IE10+ */
background: linear-gradient(top, rgba(255,255,255,1) 0%,rgba(214,214,214,1) 70%,rgba(188,188,188,1) 89%,rgba(163,163,163,1) 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#a3a3a3',GradientType=0 ); /* IE6-8 */
}
*:focus { outline:none; }
.enviar {
float:right;
width:50px;
color:#fff;
border:2px solid #002d56;
border-radius:10px;
padding:5px;
/*gradients*/
background: rgb(30,87,153); /* Old browsers */
/* IE9 SVG, needs conditional override of 'filter' to 'none' */
background: url(data:image/svg+xml;base64,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);
background: -moz-linear-gradient(top, rgba(30,87,153,1) 0%, rgba(41,137,216,1) 50%, rgba(32,124,202,1) 51%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(30,87,153,1)), color-stop(50%,rgba(41,137,216,1)), color-stop(51%,rgba(32,124,202,1))); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, rgba(30,87,153,1) 0%,rgba(41,137,216,1) 50%,rgba(32,124,202,1) 51%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, rgba(30,87,153,1) 0%,rgba(41,137,216,1) 50%,rgba(32,124,202,1) 51%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, rgba(30,87,153,1) 0%,rgba(41,137,216,1) 50%,rgba(32,124,202,1) 51%); /* IE10+ */
background: linear-gradient(top, rgba(30,87,153,1) 0%,rgba(41,137,216,1) 50%,rgba(32,124,202,1) 51%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#1e5799', endColorstr='#207cca',GradientType=0 ); /* IE6-8 */
}
.login {
margin:0 10px 0 0;
}
.perdadesenha a {
font-size:9px;
}
/**/
HTML
<ul id="menu">
<li><a href="#">EMPRESA</a>
<ul><li><a href="visaogeral.html">Visão geral</a></li>
<li><a href="historia.html">História</a></li>
<li><a href="escritorios.html">Escritórios</a></li>
<li><a href="trabalhe.html">Trabalhe conosco</a></li>
</ul>
</li>
<li><a href="#l">SERVIÇOS</a>
<ul>
<li><a href="despacho.html">Despacho</a></li>
<li><a href="transporte_rodoviario.html">Transporte Rodoviário</a></li>
<li><a href="logistica_de_liquidos.html">Logística de Líquidos</a></li>
<li><a href="frete_internacional.html">Frete Internacional</a></li>
<li><a href="licencas.html">Licenças Polícia/Exército</a></li>
</ul>
</li>
<li><a href="contato.html">CONTATO</a></li>
<li><a href="#">LOGIN</a>
<ul class="form"><form>
<li></li>
<li><label class="login">Login</label><input class="forminput" type="text" name="firstname" /><br />
<label>Senha</label> <input class="forminput" type="password" name="firstname" /></li>
<li><input class="enviar" type="submit" value="Entrar" /></li>
</form>
<a href="#"><font size="-6">Esqueceu a senha?</font></a>
</ul>
</li>
</ul>