.combined-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.coding-board { border-top-color: #25b9c5; }
@media (max-width: 960px) {
    .combined-grid { grid-template-columns: 1fr 1fr; }
    .coding-board { grid-column: 1 / -1; }
}
@media (max-width: 720px) {
    .combined-grid { grid-template-columns: 1fr; }
    .coding-board { grid-column: auto; }
}