css添加
.navbar-default .navbar-nav>.open>a, .navbar-default .navbar-nav>.open>a:focus, .navbar-default .navbar-nav>.open>a:hover{ background-color: #2b669a;}
css - bootstrap3下拉菜单点击之后怎么改变背景颜色?
原文：https://www.cnblogs.com/polly-ling/p/9619596.html
