Web Build 039

CSS basics: Reusable utility classes

Build reusable utility classes inside the persistent Workshop signup: Reusable utility classes starter project.

CSS basics

7 minutes Core Lesson 39 of 120

selectorcolorpaddingmarginfontborder

Lesson 39 of 120 0/120 lessons 0/18 missions CSS basics · 7 minutes

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Write the reusable utility classes rule

In styles.css, replace the empty rule with the exact reusable utility classes declaration block.

Target: styles.css · Inside .lesson-card.
Evidence: .lesson-card contains the lesson's primary declaration.

styles.css css

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Console text only

Instructions 7 minutes

Load exact snippets or type matching Web code. Run each task, compare the preview, then press Check to save the lesson.

Start with the Current task. Edit its named project file, press Run, compare the reviewed preview, then continue. Press Check only after every task is complete.

Write the reusable utility classes rule

In styles.css, replace the empty rule with the exact reusable utility classes declaration block.

Target styles.css · Inside .lesson-card. Evidence .lesson-card contains the lesson's primary declaration. Snippet

.lesson-card {
  margin-inline: auto;
}

Next up

Stabilize spacing and width

Add the exact gap and max-width declarations without removing the first rule.

Target styles.css · At the end of .lesson-card. Evidence The component has a stable gap and bounded width. Snippet

gap: 0.75rem;
max-width: 42rem;

Next up

Add a visible focus state

Add the exact focus-visible rule, then Run and Check.

Target styles.css · After the component rule. Evidence Keyboard focus is visible. Snippet

.lesson-card button:focus-visible {
  outline: 3px solid #5eead4;
  outline-offset: 3px;
}

Next up

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Lesson support

What to notice while you play.

Objective

Complete a project-shaped reusable utility classes build while preserving each passing edit.

Hint

Start with the Current task. Open styles.css, use Show exact edit when needed, Run, then follow the highlighted next task.

Why it matters

CSS basics becomes durable when every syntax choice is tied to a visible project outcome and a specific piece of evidence.

Common mistakes

Editing the wrong file instead of styles.css.
Replacing earlier passing work instead of preserving it for the next step.
Pressing Check before every task has passed Run.
Expecting learner HTML, CSS, or JavaScript to execute; the preview uses reviewed scene states only.

Reference

Snippets in this lesson.

Run

Render a simulated preview from the current lesson snippet.

Check

Save the lesson after the required task snippets are complete.

Hint

Show the lesson hint without changing progress.

Reset

Clear local Web lab scratch state for this browser.