Learn CSS Variables by Building a City Skyline - Step 40

It wants me to add a background property just below the background-color property, and set it to a linear-gradient. I did that but it keeps rejecting the code. What am I doing wrong?

.bb1a {
width: 70%;
height: 10%;
background-color: var(–building-color1);
background: linear-gradient(
–building-color1,
–window-color1
);
}

Hey!
Your variable names should take the below structure

--variable-name

Also,your variables need to be in a var function. var(--variable-name)

Mod edit: removed code