border and background colour problem

HTML code:

Mom and Dad

CSS code:

h1 {
color: red;
}

@font-face {
font-family: Fine Collegeimport;
src: url("Fine College.ttf");
}

#main {
font-family: Fine Collegeimport;
font-size: 1.25em;
margin: 0 25% 0 25%;
background-color: #00FF33;
border: 2px;
}

Hi
My problem is that the borders are not showing on the id-selected h1 header and the background-color #00FF33=green, goes beyond width wise the h1 header. How can I get the borders to show on the h1 header and get the background-color to only cover the width of the h1 header and not any blank spaces of the document?

Thanks
Oscar