当单击Navbar-Toggle按钮时，使页面向下移动

I'm making an Website so I can practice my Web Skills but I've run into a problem. The problem is when the Web Page is on a Mobile for example the Navbar collapse so it fits on the device but when they click the Navbar-Toggle button the Links come over the top of the header I have and I don't want this to happen. What I want to happen is when they click it, it moves all the elements down if you understand what I mean.I'm making an Website so I can practice my Web