How to do media command mathematically?

I want to reduce the margin from 35 to 15 as the screen size reduces from max to 600px

I would like margin number to be mathematically calculated as it would be cumbersome to keep adding media commands.  Is it possible to achieve it, how?

#DevMenu li
{

    padding: 0px 35px 0px 10px;
 
}

@media screen and (max-width:800px)
{
#DevMenu li
{
    padding: 0px 20px 0px 10px;
    }
}
@media screen and (max-width:600px)
{
#DevMenu li
{
    padding: 0px 10px 0px 10px;
    }
}