/* desktop devices */ @media (min-width: 768px) { aside { flex: 200px 0 0; } } /* mobile devices */ @media (max-width: 768px) { aside { width: 100%; } } body { --accent-color: #d26c6c; background-color: #e3e3e3; accent-color: var(--accent-color); display: flex; flex-flow: row wrap; } header { flex-grow: 1; flex-basis: 100%; margin: 10px; } aside { background-color: white; text-align: center; border: 1px solid black; border-radius: 3px; padding: 15px; margin: 10px; } article { background-color: white; border: 1px solid black; border-radius: 3px; padding: 15px; flex: 2 0px; margin: 10px; } footer { background-color: white; flex-grow: 1; flex-basis: 100%; margin: 10px; }