<script>
//????鼠標移入移出改變下拉菜單的背景色
????(function?mouse()?{
????????$("li").mouseenter(function?()?{
????????????$(this).css("background-color","blue").siblings().css("background-color","#fff?");

????????});
????????$("li").mouseleave(function?()?{
????????????$("li").css("background","white");
????????})
????})();
//????鼠標離開隱藏下拉菜單
????$(".dropdown-menu").mouseleave(function?()?{
????????$(this).slideUp();
????});
//????鼠標點擊按鈕再次顯示下拉菜單
????$(".btn").on("click",function?()?{
????????$(".dropdown-menu").slideDown();
????});
//????彈出被點擊的li菜單的文本內容
????$("li").click(function?()?{
????????alert($(this).html());
????})
</script>

.dropdown-menu{background-color:#202020;}

.dropdown-menu >li >a{color:#FFF;}

.dropdown-menu >li >a:focus{background-color:#000;color:#FFFFFF}

bootstrap下拉背景為黑色，選項字體為白色，點擊時選項背景加深

.dropdown-menu{

? ? ? ? background-color:#000;

? ? }