Code for background linear gradient with variable to work with percentage

You should use --building-color2 from 0% to 6% error
my code looks like the below
.bb2b {
width: 100%;
height: 100%;
background: linear-gradient(var(–building-color2) 0% 6%,var(–window-color2) 6% 9%);
}

hi there,
you need to repeat the whole term each time you enter a start or a stop marker. Only one percentage value should be after each paranthesis.