When to use Grid vs. Flexbox?
**Flexbox (1D)**: Operates on a single axis (either row OR column). Ideal for UI components like navigation bars, aligning an icon next to text, or wrapping tags. It's fluid and content-driven. **Grid (2D)**: Operates on both X and Y axes simultaneously. Perfect for macro page layouts, masonry photo galleries, and aligning complex dashboard widget tiles.
The Power of Gap
Stop using `margin` with `first-child` or `last-child` hacks to space elements out. The CSS `gap` property applies equal spacing strictly **between** child elements. Both Grid and Flexbox support it natively across all modern browsers.
Responsive Grid Magic
By utilizing `grid-template-columns: repeat(auto-fit, minmax(250px, 1fr))`, you can create auto-flowing responsive card layouts that adapt to any screen size without writing a single `@media` CSS query.