CSS Margin: 0 is not setting to 0

Question

I\'m a new comer to web designing. I created my web page layout using CSS and HTML as below. The problem is even though i set the margin to 0, the upper margin is not settin

Answer 1

Try

body {
    margin: 0;
    padding: 0;
}

instead of

.body {
    margin: 0;
    padding: 0;
}

Do not select body with class selector.