CSS basics · Lesson 3 of 12 · 7 minutes

CSS basics: Color tokens

Custom properties centralize reusable values; var() reads a token and can provide a fallback.

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Your objectives

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1
Build color tokens
Build this first target: :root with --ink: #182b2a. Keep the selector relationships intact and inspect the preview.
Hint & worked example
Custom properties centralize reusable values; var() reads a token and can provide a fallback.
The requested selectors and declarations exist outside comments.
```
:root { --ink: #182b2a; }
```
Common mistake to avoid: If the page fits one desktop viewport, no narrower viewport needs checking.
2
Extend the color tokens example
Extend your file to include: :root with --ink: #182b2a; p with color: var(--ink). Keep the selector relationships intact and inspect the preview.
Hint & worked example
Custom properties centralize reusable values; var() reads a token and can provide a fallback.
The requested selectors and declarations exist outside comments.
```
:root { --ink: #182b2a; }
p { color: var(--ink); }
```
Common mistake to avoid: Hiding all overflow always makes content accessible.
3
Verify the complete color tokens pattern
Finish the pattern with: :root with --ink: #182b2a; p with color: var(--ink); :root with --paper: #ffffff; main with background-color: var(--paper). Keep the selector relationships intact and inspect the preview.
Hint & worked example
Custom properties centralize reusable values; var() reads a token and can provide a fallback.
The requested selectors and declarations exist outside comments.
```
:root { --ink: #182b2a; }
p { color: var(--ink); }
:root { --paper: #ffffff; }
main { background-color: var(--paper); }
```
Common mistake to avoid: If the page fits one desktop viewport, no narrower viewport needs checking.

Understand the pattern

Custom properties centralize reusable values; var() reads a token and can provide a fallback.

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

:root { --ink: #182b2a; }
p { color: var(--ink); }
:root { --paper: #ffffff; }
main { background-color: var(--paper); }

Custom properties centralize reusable values; var() reads a token and can provide a fallback.

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 color tokens?If the page fits one desktop viewport, no narrower viewport needs checking.Hiding all overflow always makes content accessible.Custom properties centralize reusable values; var() reads a token and can provide a fallback.

Apply it elsewhere

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

Keep the momentum.

Complete the lab, then explain and apply the pattern.

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