body { display: grid; grid-template-rows: auto auto 1fr auto; grid-template-columns: var(--sidebar-width) 1fr; grid-template-areas: "sidebar header" "sidebar banner" "sidebar main " "sidebar footer"; justify-items: center; transition: grid-template-columns var(--transition); @media only screen and (max-width: 960px) { grid-template-columns: 0 1fr; } }