TaskQuick recap. Write CSS that uses all 4 B1-B3 fundamentals. Define :root with --gap: 12px. Apply box-sizing: border-box to *. Make .row a grid with grid-template-columns: 100px 100px 100px and gap: var(--gap). The 4 checks verify each.
Recap: Cascade, box, layout, grid
50 XP5 min
Theory
Quick recap — Modules B1-B3
Box, layout engines, grid. The 4 things you write in every real stylesheet:
- `:root` custom properties — design tokens (
--space-md,--color-bg) that flow through the cascade. - `var(--token)` — consume the token. Browsers fall back to the second arg if undefined.
- `box-sizing: border-box` — width includes padding+border. Universal selector, once, on
*. - `display: grid` + `grid-template-columns` — the modern default. Flex is for one axis, grid for two.
If any feels random, redo B1-04 / B1-06 / B2-09 / B3-02 then come back.
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