Perhaps the path to your bootstrap.min.css is collapsed? I just added this link to your header <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
and pointed to the data-target="#bs-example-navbar-collapse-1"
. It seems working now.
<html> <head> <link href="https://fonts.googleapis.com/css?family=Roboto" rel="stylesheet"> <link href="static/css/myCss.css" rel="stylesheet"> <meta charset="UTF-8"> <link href="static/css/bootstrap.min.css" rel="stylesheet" media="screen"> <link href="static/css/customIndex.css" rel="stylesheet"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <link href="static/css/bootstrap-responsive.css" rel="stylesheet"> <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"> <title>Index</title> </head> <body> <nav class="navbar navbar-default"> <div class="container-fluid"> <!-- Brand and toggle get grouped for better mobile display --> <div class="navbar-header"> <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false"> <span class="sr-only">Toggle navigation</span> <span class="icon-bar"></span> <span class="icon-bar"></span> <span class="icon-bar"></span> </button> </div> <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1"> <ul class="nav navbar-nav"> <li class="active"><a href="./index.jsp">Index</a></li> <li><a href="./profile.jsp">Profile</a></li> </ul> <ul class="nav navbar-nav navbar-right"> <li><a href="./LogoutServlet">Logout</a></li> </ul>