CSS Grid Vs Flexbox When To Use Which Practice Exam

Question 1 CSS Grid Vs Flexbox When To Use Which

justify-self in Flexbox?

No effect — use margin auto or align-self for cross axis. Aligns a single item along the inline axis within its cell. Same as justify-content + stretch (default for multi-line flex). Equivalent to flex: 0 0 auto — items don't grow or shrink.

Question 2 CSS Grid Vs Flexbox When To Use Which

Equal-width grid columns?

Put header in its own row, then position: sticky; top: 0; on the header element. Same as justify-content + stretch (default for multi-line flex). Distinct values: row-gap: 1rem; column-gap: 2rem; grid-template-columns: repeat(3, 1fr);

Question 3 CSS Grid Vs Flexbox When To Use Which

display: contents on a flex/grid child?

Put header in its own row, then position: sticky; top: 0; on the header element. Removes the box but children inherit parent's flex/grid context — useful for screen reader semantics. Older screen readers may skip semantic role — improving in modern browsers but verify. Names cells in a grid for visual layout assignment.

Question 4 CSS Grid Vs Flexbox When To Use Which

Why doesn't align-content work on single-row flex?

align-content controls multiple rows; with one row, no effect — use align-items instead. grid-template-columns: 250px 1fr; Equivalent to flex: 0 0 auto — items don't grow or shrink. grid-template-columns: repeat(3, 1fr);

Question 5 CSS Grid Vs Flexbox When To Use Which

grid-area numeric form?

grid-area: row-start / col-start / row-end / col-end; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); Reorders visual position; can break screen reader and keyboard navigation. Use sparingly. Likely line-height or baseline; display: flex; align-items: center; on parent fixes it.

Question 6 CSS Grid Vs Flexbox When To Use Which

Stretch a single grid item to full row?

Yes — multi-level alignment without restructuring DOM, when full browser support lands. Grid is 2D, more powerful for layouts; flex remains best for 1D component internals. No effect — use margin auto or align-self for cross axis. grid-column: 1 / -1;

Question 7 CSS Grid Vs Flexbox When To Use Which

Holy Grail layout?

scroll-snap-type on container + scroll-snap-align on children — carousel-like scrolling. Both group selectors; `:where()` has zero specificity, `:is()` uses highest in the list. Grid: grid-template-columns: max-content 1fr; + gap. Grid: grid-template: 'header header header' auto 'nav main aside' 1fr 'footer footer footer' auto / 200px 1fr 200px;

Question 8 CSS Grid Vs Flexbox When To Use Which

Auto-fill empty space with one item?

grid-column: 1 / -1; — span all columns. Set min-width: 0; — flex items default to min-width: auto which prevents this. Grid rows stretch by default — children align to row height. Combines flex-direction + flex-wrap: flex-flow: row wrap;

Question 9 CSS Grid Vs Flexbox When To Use Which

One-line summary: when Grid vs Flexbox?

Grid: 2D layout (rows AND columns), known structure.
Flexbox: 1D layout (row OR column), content-driven. grid-column: 1 / -1 — line names go to last. @container (min-width: 400px) { ... } + container-type: inline-size; on parent. flex-start

Question 10 CSS Grid Vs Flexbox When To Use Which

Tabbing with order?

grid-column: 1 / -1 — line names go to last. Tab still follows DOM; reordering visually with order can break keyboard nav. Re-order DOM if possible. order: -1 (flex/grid) — but it harms accessibility/tab order. Reserve for visual reorder where the source order is intentional. img { width:100%; height:100%; object-fit: cover; }

Question 11 CSS Grid Vs Flexbox When To Use Which

Scroll snap?

scroll-snap-type on container + scroll-snap-align on children — carousel-like scrolling. Pushes the item to consume free space — useful for "flex-end" of a single item. Default flex-shrink: 1 usually shrinks. If not, check min-width (auto) on item or fixed children inside. Likely line-height or baseline; display: flex; align-items: center; on parent fixes it.

Question 12 CSS Grid Vs Flexbox When To Use Which

Order items differently than DOM?

order: -1 (flex/grid) — but it harms accessibility/tab order. Reserve for visual reorder where the source order is intentional. align-items: per item along the cross axis.
align-content: distributes wrapped lines (multiple rows) along the cross axis. After wrap, item should have flex-basis: 100%; to take full row. Likely line-height or baseline; display: flex; align-items: center; on parent fixes it.

Question 13 CSS Grid Vs Flexbox When To Use Which

Make a card image fill its grid cell?

img { width:100%; height:100%; object-fit: cover; } aspect-ratio: 16 / 9; on the child. @container (min-width: 400px) { ... } + container-type: inline-size; on parent. Body display:grid, grid-template-rows: 1fr auto; footer auto, content 1fr.

Question 14 CSS Grid Vs Flexbox When To Use Which

Push the last flex item to the end?

grid-column: 1 / -1; — span all columns. justify-content: space-between (no edge gap) or space-evenly (equal everywhere). grid-template-columns: subgrid; on the child. :last-child { margin-left: auto; } — common nav pattern with a logo on left and links on right.

Question 15 CSS Grid Vs Flexbox When To Use Which

What is `:has()` selector?

Parent selector: div:has(img) — applies to divs containing images. Game-changer for layout-adjacent styling. Useful to hide overflow without scrollbars; can clip absolutely-positioned children unintentionally. display: grid; place-items: center; — shorthand for align + justify items. aspect-ratio: 16 / 9; — modern alternative to padding-top hacks.

Question 16 CSS Grid Vs Flexbox When To Use Which

Why do my grid lines look thicker?

Rows/columns created automatically when items overflow explicit grid — sized by grid-auto-rows/columns. justify-self: end; align-self: end; on the item, or place-self: end;. gap is the space between cells, often confused with borders. Border collapse doesn't apply. row: fills row-by-row (default).
column: fills column-by-column.

Question 17 CSS Grid Vs Flexbox When To Use Which

min-content vs max-content for grid track?

min-content: smallest content width (longest word).
max-content: width to fit content without wrapping. Single child centering inside a known box: margin auto, position absolute + transform, or place-content if you want flex/grid. grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); Tab still follows DOM; reordering visually with order can break keyboard nav. Re-order DOM if possible.

Question 18 CSS Grid Vs Flexbox When To Use Which

overflow: hidden inside flex parent?

All modern browsers and IE11 (with quirks). Flex children with no content or zero flex-basis can collapse. Set min size. Useful to hide overflow without scrollbars; can clip absolutely-positioned children unintentionally. width: calc((100% - 2*1rem) / 3); — 3 columns with 1rem gap (flex era trick; modern uses gap).

Question 19 CSS Grid Vs Flexbox When To Use Which

Browser support for Grid?

If you're thinking "row OR column", use Flex. If "rows AND columns" with named positions, use Grid. cqw, cqh, cqi, cqb, cqmin, cqmax — relative to container. Modern browsers since 2017. Subgrid since Firefox 71 (2019), Safari 16 (2022), Chrome 117 (2023). stretch — children expand to fill the cross axis.

Question 20 CSS Grid Vs Flexbox When To Use Which

Container query units?

@container (min-width: 400px) { ... } + container-type: inline-size; on parent. grid-template-columns: calc(50% - 1rem) 1fr; — supported, calculate around gaps. Yes — multi-level alignment without restructuring DOM, when full browser support lands. cqw, cqh, cqi, cqb, cqmin, cqmax — relative to container.

Question 21 CSS Grid Vs Flexbox When To Use Which

Why is my flex child wider than expected?

flex-basis sets initial size; flex-grow distributes extra space. Set flex-basis: 0 for purely proportional widths. Naming grid-template-areas automatically creates 4 line names per area (e.g., header-start, header-end). Chrome/Firefox DevTools show grid lines, names, and gaps — invaluable for debugging. grid-column: 1 / -1;

Question 22 CSS Grid Vs Flexbox When To Use Which

space-evenly?

Equal space everywhere, including edges. Needed because grid items have implicit `min-height: auto`, which prevents inner content from constraining. display:flex; align-items:center; IE10/11 have an older grid spec — use feature query @supports (display: grid) to opt-in.

Question 23 CSS Grid Vs Flexbox When To Use Which

display: contents accessibility issue?

justify-content: space-between (no edge gap) or space-evenly (equal everywhere). grid-column: 1 / 4; (or grid-column-start: 1; grid-column-end: 4;). Older screen readers may skip semantic role — improving in modern browsers but verify. Distinct values: row-gap: 1rem; column-gap: 2rem;

Question 24 CSS Grid Vs Flexbox When To Use Which

CSS reset implications for flex/grid?

Images without max-width can blow out the layout — set max-width: 100%; height: auto;. Chrome/Firefox DevTools show grid lines, names, and gaps — invaluable for debugging. Most resets are fine; ensure box-sizing: border-box for predictable sizing inside fixed tracks. Equivalent to flex: 0 1 auto — items shrink but don't grow.

Question 25 CSS Grid Vs Flexbox When To Use Which

Combining repeat with minmax and fr?

No effect — use margin auto or align-self for cross axis. Modern browsers since 2017. Subgrid since Firefox 71 (2019), Safari 16 (2022), Chrome 117 (2023). repeat(3, minmax(200px, 1fr)) — 3 columns, each between 200px and 1fr share. display: inline-grid; — grid container flows inline with text.

Question 26 CSS Grid Vs Flexbox When To Use Which

Why is my responsive grid jumping?

Each cell flows naturally; complex layouts may behave unexpectedly across pages. 1fr distributes remaining space; auto sizes by content. gap is separate from margin/padding; margins on flex children still apply normally. auto-fit collapses tracks when items can't shrink past minmax minimum — choose minimum carefully.

Question 27 CSS Grid Vs Flexbox When To Use Which

grid-template-rows?

repeat(3, [col-start] 1fr [col-end]) — multiple lines with same name. Defines explicit row sizes: grid-template-rows: 100px 1fr auto; Items with different font sizes may misalign. Use align-items: baseline or unify line-height. Each cell flows naturally; complex layouts may behave unexpectedly across pages.

Question 28 CSS Grid Vs Flexbox When To Use Which

Use flex for sticky aside, scroll content?

Different order numbers can mask layout intent; comment why or restructure DOM. Flex row: aside fixed width, main scrolls — needs main's overflow:auto and parent height. Default; items render in source order. Negative orders come first. grid-template-rows: subgrid; — same idea, vertical alignment with parent.

Question 29 CSS Grid Vs Flexbox When To Use Which

Resources to learn more?

CSS Tricks "A Complete Guide to Flexbox" and "A Complete Guide to Grid" — definitive references. @container (min-width: 400px) { ... } + container-type: inline-size; on parent. inline-size (width), block-size (height). Same fix: min-width: 0; overflow: hidden; as needed.

Question 30 CSS Grid Vs Flexbox When To Use Which

Center with Grid (modern)?

Same toolset highlights flex containers and shows alignment. Parent selector: div:has(img) — applies to divs containing images. Game-changer for layout-adjacent styling. gap is the space between cells, often confused with borders. Border collapse doesn't apply. display: grid; place-items: center; — shorthand for align + justify items.

Question 31 CSS Grid Vs Flexbox When To Use Which

grid-area on a child?

cover: fills box, may crop.
contain: fits inside, may letterbox. aspect-ratio: 16 / 9; on the child. width: calc((100% - 2*1rem) / 3); — 3 columns with 1rem gap (flex era trick; modern uses gap). grid-area: header; — assigns child to a named area.

Question 32 CSS Grid Vs Flexbox When To Use Which

minmax() in grid?

Pushes the item to consume free space — useful for "flex-end" of a single item. cqw, cqh, cqi, cqb, cqmin, cqmax — relative to container. minmax(100px, 1fr) — col sizes between 100px and 1fr. If you're thinking "row OR column", use Flex. If "rows AND columns" with named positions, use Grid.

Question 33 CSS Grid Vs Flexbox When To Use Which

Pure CSS sticky footer with grid?

Same fix: min-width: 0; overflow: hidden; as needed. Body display:grid, grid-template-rows: 1fr auto; footer auto, content 1fr. align-content controls multiple rows; with one row, no effect — use align-items instead. No issue; just remember each new flex context starts with default alignment.

Question 34 CSS Grid Vs Flexbox When To Use Which

flex-flow shorthand?

Rows/columns created automatically when items overflow explicit grid — sized by grid-auto-rows/columns. gap is the space between cells, often confused with borders. Border collapse doesn't apply. Tab order follows DOM, not visual order — avoid order and grid-area for non-cosmetic reflow. Combines flex-direction + flex-wrap: flex-flow: row wrap;

Question 35 CSS Grid Vs Flexbox When To Use Which

Center text vertically in a header bar?

Spec adds grid-template-rows: masonry; — partial impl in Firefox. display:flex; align-items:center; Combines rows, columns, and areas in one declaration. stretch — children expand to fill the cross axis.

Question 36 CSS Grid Vs Flexbox When To Use Which

align-content options?

1D layout; items align along one axis with optional gap and spacing. Each cell flows naturally; complex layouts may behave unexpectedly across pages. Same as justify-content + stretch (default for multi-line flex). cover: fills box, may crop.
contain: fits inside, may letterbox.

Question 37 CSS Grid Vs Flexbox When To Use Which

flex-basis with content keyword?

align-items: stretch (default) on flex container — children fill the cross axis. row — main axis is horizontal, cross axis vertical. flex-basis: content; — sized by content; newer spec, less universal support. Children need to be flex/grid items themselves or have explicit dimensions; flex item is a block by default.

Question 38 CSS Grid Vs Flexbox When To Use Which

View transitions and layout?

Distinct values: row-gap: 1rem; column-gap: 2rem; View Transitions API works across flex/grid; transitions interpolate position smoothly. All modern browsers and IE11 (with quirks). minmax(100px, 1fr) — col sizes between 100px and 1fr.

Question 39 CSS Grid Vs Flexbox When To Use Which

Use case: chat layout?

Item tries to be 100% of container, then flex shrinks it back — usually behaves correctly but check min-width. Older screen readers may skip semantic role — improving in modern browsers but verify. Flex column main, scrollable body flex:1, input at bottom with align-self:flex-end. Flex children with no content or zero flex-basis can collapse. Set min size.

Question 40 CSS Grid Vs Flexbox When To Use Which

Multi-column layout (column-count)?

Three nested flex containers OR justify-content: space-between with three direct children grouping internal items. Grid: grid-template-columns: repeat(3, auto); — sized by largest content. Old API for newspaper-style columns; works for body text but not interactive components. grid-template-columns: calc(50% - 1rem) 1fr; — supported, calculate around gaps.

Question 41 CSS Grid Vs Flexbox When To Use Which

Subgrid track inheritance — what's inherited?

Track sizes from the explicit grid; named lines also pass through. The direction children flow in a flex container — controlled by flex-direction. Images without max-width can blow out the layout — set max-width: 100%; height: auto;. Grid: 2-column form rows + 1-column section headers.

Question 42 CSS Grid Vs Flexbox When To Use Which

Named lines?

display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; display:flex; flex-wrap:wrap; gap:1rem; with each card flex: 1 1 220px; row, row-reverse, column, column-reverse. grid-template-columns: [start] 200px [main-start] 1fr [end]; — reference by name.

Question 43 CSS Grid Vs Flexbox When To Use Which

Make a flexbox card grid?

repeat(3, minmax(200px, 1fr)) — 3 columns, each between 200px and 1fr share. .card { display: flex; flex-direction: column; }; body flex: 1; footer at end. display:flex; flex-wrap:wrap; gap:1rem; with each card flex: 1 1 220px; :last-child { margin-left: auto; } — common nav pattern with a logo on left and links on right.

Question 44 CSS Grid Vs Flexbox When To Use Which

SVG sizing in flex?

Count from the end: -1 is last, -2 is second to last, etc. IE10/11 have an older grid spec — use feature query @supports (display: grid) to opt-in. Without intrinsic width, SVG can collapse. Set explicit width/height or use viewBox + flex-basis. Page breaks can be tricky inside flex containers; use page-break-inside: avoid; on items.

Question 45 CSS Grid Vs Flexbox When To Use Which

align-items vs align-content?

align-items: per item along the cross axis.
align-content: distributes wrapped lines (multiple rows) along the cross axis. Tools like cssgrid-generator.netlify.app let you visually craft grid templates. Old API for newspaper-style columns; works for body text but not interactive components. Each cell flows naturally; complex layouts may behave unexpectedly across pages.

Question 46 CSS Grid Vs Flexbox When To Use Which

Use case for inline-grid vs grid?

@media (max-width: 768px) { grid-template-columns: 1fr; } 0: child gets only grow share, ignoring content size.
auto: child starts at content size, then grows/shrinks. Overrides parent's align-items for a single child. inline-grid creates an inline-level grid container — flows with text. Rare, but useful for badge-like grids inside paragraphs.

Question 47 CSS Grid Vs Flexbox When To Use Which

container-type: size vs inline-size?

Yes — multi-level alignment without restructuring DOM, when full browser support lands. repeat(3, minmax(200px, 1fr)) — 3 columns, each between 200px and 1fr share. inline-size: width-only queries.
size: both axes — requires fixed height too. grid-column: 1 / -1;

Question 48 CSS Grid Vs Flexbox When To Use Which

Inline-block alternative pattern?

Grid is 2D, more powerful for layouts; flex remains best for 1D component internals. Grid wraps to next implicit row automatically; flex wraps when flex-wrap is enabled. Modern layouts prefer flex/grid; inline-block had whitespace issues and limited alignment. 1D layout; items align along one axis with optional gap and spacing.

Question 49 CSS Grid Vs Flexbox When To Use Which

Subgrid with row direction?

grid-template-rows: subgrid; — same idea, vertical alignment with parent. grid-template-columns: subgrid; on the child. repeat(3, minmax(200px, 1fr)) — 3 columns, each between 200px and 1fr share. Same as justify-content + stretch (default for multi-line flex).

Question 50 CSS Grid Vs Flexbox When To Use Which

Gap between items?

Both support gap: 1rem; — replaces margin hacks. Promotes element to GPU layer; can help with scroll perf; don't overuse. Aligning labels and inputs into clean rows/columns is much easier with grid-template-columns. grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));