Below, only `sm:grid-cols-2` and `md:grid-cols-4` are used. For screens smaller than `sm` (640px), Tailwind's grid system will effectively render one column per item. While this often works, it relies on this default behavior and isn't explicit. If other base `grid-cols-*` were set elsewhere or if Tailwind's defaults change, this could lead to unexpected behavior.
Observation: On very small screens, this grid will show 1 column. This happens because no `grid-cols-*` is specified for the smallest breakpoint, so grid items stack by default.
Here, `grid-cols-1` is explicitly set for the smallest screens. This makes the intended layout clear at all breakpoints and avoids relying on implicit defaults.
Observation: Explicitly setting `grid-cols-1` ensures one column on small screens, then it transitions to 2 columns at `sm` and 4 columns at `md`. This is the preferred, clearer approach.
Resize your browser window to see the differences in behavior (though both might appear similar for 1 column on small screens, the explicitness matters for code clarity and maintainability).