Help! My Website Does Not Work In all screen sizes

I have a problem with my website not working for all screen sizes. I am not using tables I am building it with Divs. When looking at it on a smaller screen resolution text is farther over on the screen then it should be. Any help would be appreciated thanks.

Use Divs width in %(percent) and if to change the text and image size according to resolution then use PHP or javascript to first catch the actual resolution and then give the amount of percent to those image and text sizes.

I will let you know the total process on how to get resolution using PHP or javascript on your request.

Thanks