refactor: use border radius variable

frappe/public/scss/website/footer.scss

@@ -94,7 +94,7 @@
 			max-width: 300px;
 			border: 1px solid var(--dark-border-color);
 			box-shadow: none;
-			border-radius: 0.375rem;
+			border-radius: var(--border-radius);
 			font-size: $font-size-sm;
 		}
 	}