Layout and responsive · Lesson 12 of 14 · 10 minutes

Layout and responsive: Source order

Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.

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Your objectives

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1
Build source order
Build this first target: .layout with display: flex. Keep the selector relationships intact and inspect the preview.
Hint & worked example
Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.
The requested selectors and declarations exist outside comments.
```
.layout { display: flex; }
```
Common mistake to avoid: If the page fits one desktop viewport, no narrower viewport needs checking.
2
Extend the source order example
Extend your file to include: .layout with display: flex; .layout with flex-direction: column. Keep the selector relationships intact and inspect the preview.
Hint & worked example
Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.
The requested selectors and declarations exist outside comments.
```
.layout { display: flex; }
.layout { flex-direction: column; }
```
Common mistake to avoid: Hiding all overflow always makes content accessible.
3
Verify the complete source order pattern
Finish the pattern with: .layout with display: flex; .layout with flex-direction: column; @media(min-width:48rem) — .layout with flex-direction: row. Keep the selector relationships intact and inspect the preview.
Hint & worked example
Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.
The requested selectors and declarations exist outside comments.
```
.layout { display: flex; }
.layout { flex-direction: column; }
@media (min-width: 48rem) { .layout { flex-direction: row; } }
```
Common mistake to avoid: If the page fits one desktop viewport, no narrower viewport needs checking.

Understand the pattern

Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.

Misconceptions to reject

If the page fits one desktop viewport, no narrower viewport needs checking.
Hiding all overflow always makes content accessible.

The preview is a sanitized subset, not a full browser compatibility test.

Worked example and expected result

.layout { display: flex; }
.layout { flex-direction: column; }
@media (min-width: 48rem) { .layout { flex-direction: row; } }

Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.

Try a variation

Adapt the final example to a different project name while retaining its structure and relationships. A different context still needs a real browser and accessibility check.

Explain it

Which statement correctly explains source order?Hiding all overflow always makes content accessible.Visual reordering can differ from keyboard and reading order. Preserve meaningful source order instead.If the page fits one desktop viewport, no narrower viewport needs checking.

Apply it elsewhere

You reuse source order in a different project. What must still be verified?The resulting layout, focus behavior, and readability at the target viewport sizes.Nothing; passing a single exercise guarantees every future use.Only whether the source code has the same number of lines.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Layout and responsive: Overflow prevention Try an incident drill

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MDN: CSS styling