I used a meta viewport tag - <meta name="viewport" content="width=device-width,height=device-height-initial-scale=1.0,user-scalable=no"> and also made sure that the document was no larger than 320x212px, try:
body {
width: 100%;
height: 100%;
padding: 0 0 0 0;
margin: 0 0 0 0;
overflow: hidden;
}
html {
width: 320px;
height: 210px;
padding: 0 0 0 0;
margin: 0 0 0 0;
overflow: hidden;
}