Designing a Layout for All Size Screens?

Is there any way to create a layout that will look exactly the same on any

size computer screen? I find it frustrating when I create a precise layout

only to see it jumbled on a smaller or larger screen. There must be some

way to "lock down" the proportions and/or positions of the pods so that

they remain as I design them, but how? Is there no way to accomplish this?

No trick to overlapping pods or anything?