Build CSS flexbox layouts visually — set justify-content, align-items, flex-wrap, gap and per-item grow/shrink/order values. Copy the container and item CSS instantly.
Flexbox is a one-dimensional layout model — it distributes space along a single axis (row or column). The container controls alignment via justify-content (main axis) and align-items (cross axis). Individual items can override alignment with align-self, change order with order, or grow to fill remaining space with flex-grow. The shorthand flex: 1 is equivalent to flex-grow: 1; flex-shrink: 1; flex-basis: 0%. Use flex-wrap: wrap to allow items to flow onto multiple lines. For two-dimensional layouts, CSS Grid is usually a better fit.