Intermediate interview questions in CSS & Design Systems, page 3
When container queries beat media queries
Media queries react to viewport, container queries react to a parent's size, ideal for reusable components; set container-type on an ancestor then query it.
Styling a parent with the :has() selector
:has() matches an element that contains or relates to a given selector, enabling upward styling; figure:has(figcaption) targets captioned figures.
Why Oklch beats HSL for color variations
HSL lightness is not perceptually uniform so equal steps look uneven, Oklch keeps perceived lightness consistent across hues, giving predictable hover and palette scales.
How BEM tames specificity and !important
BEM names block, element, modifier as flat single classes, keeping specificity low and equal, removing the need for deep selectors and !important.
What design tokens are and why they matter
Tokens are named, platform-agnostic design decisions stored centrally, enabling consistency, theming, and one-place updates.
Transforming tokens for multiple platforms
A transformer like Style Dictionary parses JSON, applies platform transforms, and renders formatted outputs (CSS vars, Swift, Kotlin) via configured platforms.
Versioning and distributing token updates safely
Publish tokens as a semver package, bump major on breaking changes, deprecate before removing, communicate via changelogs and migration guides.
Architecting multi-brand, dark-mode theming
Tier tokens into primitive, semantic, and component layers; components consume semantic tokens; themes swap by remapping semantic-to-primitive on a scope like data-theme.
Clickable card: div onClick versus anchor tag
Use an a tag for navigation; it is focusable, keyboard-activatable, announced as a link, and supports open-in-new-tab; a div onClick loses all of that without manual ARIA work.
The role of Storybook in a design system
Storybook renders components in isolation across states, serving as living documentation, a development sandbox, and a base for visual and accessibility testing.
Tokens as a single source of truth pipeline
Define tiered tokens in standardized JSON, transform per platform with a build tool, publish versioned packages, and automate in CI.
Contributing a new component variant
Align with maintainers first, follow guidelines, implement with API and tokens, add stories, docs, and tests, then open a PR for review.
Delivering an urgent design system hotfix
Branch from the released tag, apply a minimal fix, add a regression test, ship a patch version, then forward-port to main.
Structuring docs for multiple audiences
Layer docs by audience, give developers API and code, designers usage and design guidelines, PMs principles and coverage, with shared foundations like tokens and accessibility.
Cross-platform themeable token system
Tier tokens with semantic theme sets that remap primitives per mode, transform to each platform's theme mechanism, and deliver versioned packages.
What problem do CSS Cascade Layers solve?
Layers create explicit priority bands, layer order beats specificity inside, and you control override without selector hacks.
Structure CSS layers for reset, vendor, and components
Declare layer order upfront, place reset earliest, vendor next, your components last so they win.
Center a div with Flexbox on the parent
Set display flex on parent, justify-content center for the main axis, align-items center for the cross axis.
CSS Modules versus BEM for encapsulation
CSS Modules scope via build-time hashed class names automatically; BEM scopes via disciplined human naming with no tooling.
Designing a Card component's configurable API
Expose content via composition (slots/children), expose constrained variants as enums, lock spacing and brand tokens.
We are hiring for this. Every open role lists the topics its interview covers, so you can prepare for the real thing rather than guessing.
See open roles