sking

I have watched this tutorial on making a nav bar. I don't understand why they don't fully explain how to make the other nav buttons active here. I see not help link. Only this forum. Once you hover over a button, the color changes, but you cannot click a button and navigate to another page in the tutorial to see in fact that the button I clicked on has CHANGED COLOR from white to Green (active color) When the page loads, the default home button is green. I hover my house over any of the other buttons to change to green. So when you click on them, how do you make it stay this green color and the home button will then be white like the others? What is required in the css to make this happen? Is there a tutorial on this?