CSS • Chapter 25 • Foundations to Production
Typography Basics
Every topic includes a CSS/HTML coding example, ten focused teaching examples, code explanation, expected result, practice, and responsive/translated-layout checks.
25.1 font-family
font-family is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size. The goal is to connect the syntax to the browser's layout and cascade decisions rather than memorize a property name.
For font-family in Chapter 25, inspect the matched selector, computed value, containing block or formatting context, intrinsic size, and any min/max constraints. When translation is enabled, also inspect whether longer text or RTL direction changes the available inline space.
Start with one small example for font-family, resize the viewport, increase text size, translate the label, and add a competing rule. This shows whether the technique remains predictable under real content rather than only in a fixed desktop mockup. This explanation is specific to Chapter 25, topic 1.
Concept in plain language
font-family is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size.
10 teaching examples
Example 1: Smallest useful case
Build a minimal notification for font-family. Keep only the declarations needed to see the behavior clearly, then inspect the computed styles. Chapter 25, topic 1, example 1.
Example 2: Change one value
Change one important CSS value in the language selector example for font-family. Predict the visual difference before reloading the page. Chapter 25, topic 1, example 2.
Example 3: Narrow-screen test
Test font-family in the course card at 320px, 375px, and tablet width. Watch for min-content sizing, unwrapped text, and elements that refuse to shrink. Chapter 25, topic 1, example 3.
Example 4: Translated-text test
Translate the navigation bar into a language with longer labels while using font-family. Confirm buttons, headings, and navigation wrap without widening the page. Chapter 25, topic 1, example 4.
Example 5: Arabic/Persian test
Switch the article to Arabic or Persian. Verify logical spacing, start/end alignment, sidebar direction, and LTR code islands. Chapter 25, topic 1, example 5.
Example 6: Accessibility test
Check font-family in the profile panel with keyboard focus, zoom, reduced motion, forced colors, and high text scaling where relevant. Chapter 25, topic 1, example 6.
Example 7: Cascade test
Add a competing rule to the search form and determine why the declaration for font-family wins or loses using the browser's Styles and Computed panels. Chapter 25, topic 1, example 7.
Example 8: Content-stress test
Fill the dashboard with very long words, URLs, translated text, images, and nested controls. Adjust font-family without hiding meaningful content. Chapter 25, topic 1, example 8.
Example 9: Refactoring test
Rewrite the photo gallery so font-family uses reusable tokens, logical properties, or a component class while preserving the same behavior. Chapter 25, topic 1, example 9.
Example 10: Production review
Review font-family in the pricing table for browser support, fallback behavior, RTL, small screens, print, motion preferences, and maintainability. Chapter 25, topic 1, example 10.
CSS/HTML coding example
<!-- HTML -->
<p class="text" lang="en">A long paragraph demonstrates the typography rule in a real content block.</p>
<style>
.text{font-family:Georgia,serif}
</style>Step-by-step code explanation
- Identify the selector and declaration that demonstrate font-family.
- Read the HTML structure first so you know which box or relationship the CSS is styling.
- The declaration demonstrates font-family on paragraph text.
- Resize the viewport and test long translated content. Confirm that flex/grid items use min-width:0 where needed and that only code or genuinely wide content scrolls locally.
- Switch to Arabic or Persian and verify logical start/end spacing, text alignment, sidebar direction, and LTR isolation for code.
Expected result: The browser visibly demonstrates font-family without requiring the page to exceed the viewport width. If the example contains wide code, only the code block scrolls horizontally. This expected result belongs to Chapter 25, topic 1.
Practice exercise
Build a fresh example for font-family from Chapter 25. Change one value, inspect the computed styles, test at 320px and tablet width, translate the visible text, switch the page to RTL, and explain why the final declaration or layout behavior occurs.
25.2 font-size
font-size is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size. The goal is to connect the syntax to the browser's layout and cascade decisions rather than memorize a property name.
For font-size in Chapter 25, inspect the matched selector, computed value, containing block or formatting context, intrinsic size, and any min/max constraints. When translation is enabled, also inspect whether longer text or RTL direction changes the available inline space.
Start with one small example for font-size, resize the viewport, increase text size, translate the label, and add a competing rule. This shows whether the technique remains predictable under real content rather than only in a fixed desktop mockup. This explanation is specific to Chapter 25, topic 2.
Concept in plain language
font-size is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size.
10 teaching examples
Example 1: Smallest useful case
Build a minimal navigation bar for font-size. Keep only the declarations needed to see the behavior clearly, then inspect the computed styles. Chapter 25, topic 2, example 1.
Example 2: Change one value
Change one important CSS value in the article example for font-size. Predict the visual difference before reloading the page. Chapter 25, topic 2, example 2.
Example 3: Narrow-screen test
Test font-size in the profile panel at 320px, 375px, and tablet width. Watch for min-content sizing, unwrapped text, and elements that refuse to shrink. Chapter 25, topic 2, example 3.
Example 4: Translated-text test
Translate the search form into a language with longer labels while using font-size. Confirm buttons, headings, and navigation wrap without widening the page. Chapter 25, topic 2, example 4.
Example 5: Arabic/Persian test
Switch the dashboard to Arabic or Persian. Verify logical spacing, start/end alignment, sidebar direction, and LTR code islands. Chapter 25, topic 2, example 5.
Example 6: Accessibility test
Check font-size in the photo gallery with keyboard focus, zoom, reduced motion, forced colors, and high text scaling where relevant. Chapter 25, topic 2, example 6.
Example 7: Cascade test
Add a competing rule to the pricing table and determine why the declaration for font-size wins or loses using the browser's Styles and Computed panels. Chapter 25, topic 2, example 7.
Example 8: Content-stress test
Fill the lesson sidebar with very long words, URLs, translated text, images, and nested controls. Adjust font-size without hiding meaningful content. Chapter 25, topic 2, example 8.
Example 9: Refactoring test
Rewrite the contact form so font-size uses reusable tokens, logical properties, or a component class while preserving the same behavior. Chapter 25, topic 2, example 9.
Example 10: Production review
Review font-size in the button group for browser support, fallback behavior, RTL, small screens, print, motion preferences, and maintainability. Chapter 25, topic 2, example 10.
CSS/HTML coding example
<!-- HTML -->
<p class="text" lang="en">A long paragraph demonstrates the typography rule in a real content block.</p>
<style>
.text{font-size:clamp(1rem,2vw,1.5rem)}
</style>Step-by-step code explanation
- Identify the selector and declaration that demonstrate font-size.
- Read the HTML structure first so you know which box or relationship the CSS is styling.
- The declaration demonstrates font-size on paragraph text.
- Resize the viewport and test long translated content. Confirm that flex/grid items use min-width:0 where needed and that only code or genuinely wide content scrolls locally.
- Switch to Arabic or Persian and verify logical start/end spacing, text alignment, sidebar direction, and LTR isolation for code.
Expected result: The browser visibly demonstrates font-size without requiring the page to exceed the viewport width. If the example contains wide code, only the code block scrolls horizontally. This expected result belongs to Chapter 25, topic 2.
Practice exercise
Build a fresh example for font-size from Chapter 25. Change one value, inspect the computed styles, test at 320px and tablet width, translate the visible text, switch the page to RTL, and explain why the final declaration or layout behavior occurs.
25.3 font-weight
font-weight is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size. The goal is to connect the syntax to the browser's layout and cascade decisions rather than memorize a property name.
For font-weight in Chapter 25, inspect the matched selector, computed value, containing block or formatting context, intrinsic size, and any min/max constraints. When translation is enabled, also inspect whether longer text or RTL direction changes the available inline space.
Start with one small example for font-weight, resize the viewport, increase text size, translate the label, and add a competing rule. This shows whether the technique remains predictable under real content rather than only in a fixed desktop mockup. This explanation is specific to Chapter 25, topic 3.
Concept in plain language
font-weight is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size.
10 teaching examples
Example 1: Smallest useful case
Build a minimal search form for font-weight. Keep only the declarations needed to see the behavior clearly, then inspect the computed styles. Chapter 25, topic 3, example 1.
Example 2: Change one value
Change one important CSS value in the dashboard example for font-weight. Predict the visual difference before reloading the page. Chapter 25, topic 3, example 2.
Example 3: Narrow-screen test
Test font-weight in the photo gallery at 320px, 375px, and tablet width. Watch for min-content sizing, unwrapped text, and elements that refuse to shrink. Chapter 25, topic 3, example 3.
Example 4: Translated-text test
Translate the pricing table into a language with longer labels while using font-weight. Confirm buttons, headings, and navigation wrap without widening the page. Chapter 25, topic 3, example 4.
Example 5: Arabic/Persian test
Switch the lesson sidebar to Arabic or Persian. Verify logical spacing, start/end alignment, sidebar direction, and LTR code islands. Chapter 25, topic 3, example 5.
Example 6: Accessibility test
Check font-weight in the contact form with keyboard focus, zoom, reduced motion, forced colors, and high text scaling where relevant. Chapter 25, topic 3, example 6.
Example 7: Cascade test
Add a competing rule to the button group and determine why the declaration for font-weight wins or loses using the browser's Styles and Computed panels. Chapter 25, topic 3, example 7.
Example 8: Content-stress test
Fill the data table with very long words, URLs, translated text, images, and nested controls. Adjust font-weight without hiding meaningful content. Chapter 25, topic 3, example 8.
Example 9: Refactoring test
Rewrite the media player so font-weight uses reusable tokens, logical properties, or a component class while preserving the same behavior. Chapter 25, topic 3, example 9.
Example 10: Production review
Review font-weight in the notification for browser support, fallback behavior, RTL, small screens, print, motion preferences, and maintainability. Chapter 25, topic 3, example 10.
CSS/HTML coding example
<!-- HTML -->
<p class="text" lang="en">A long paragraph demonstrates the typography rule in a real content block.</p>
<style>
.text{font-weight:800}
</style>Step-by-step code explanation
- Identify the selector and declaration that demonstrate font-weight.
- Read the HTML structure first so you know which box or relationship the CSS is styling.
- The declaration demonstrates font-weight on paragraph text.
- Resize the viewport and test long translated content. Confirm that flex/grid items use min-width:0 where needed and that only code or genuinely wide content scrolls locally.
- Switch to Arabic or Persian and verify logical start/end spacing, text alignment, sidebar direction, and LTR isolation for code.
Expected result: The browser visibly demonstrates font-weight without requiring the page to exceed the viewport width. If the example contains wide code, only the code block scrolls horizontally. This expected result belongs to Chapter 25, topic 3.
Practice exercise
Build a fresh example for font-weight from Chapter 25. Change one value, inspect the computed styles, test at 320px and tablet width, translate the visible text, switch the page to RTL, and explain why the final declaration or layout behavior occurs.
25.4 font-style
font-style is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size. The goal is to connect the syntax to the browser's layout and cascade decisions rather than memorize a property name.
For font-style in Chapter 25, inspect the matched selector, computed value, containing block or formatting context, intrinsic size, and any min/max constraints. When translation is enabled, also inspect whether longer text or RTL direction changes the available inline space.
Start with one small example for font-style, resize the viewport, increase text size, translate the label, and add a competing rule. This shows whether the technique remains predictable under real content rather than only in a fixed desktop mockup. This explanation is specific to Chapter 25, topic 4.
Concept in plain language
font-style is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size.
10 teaching examples
Example 1: Smallest useful case
Build a minimal pricing table for font-style. Keep only the declarations needed to see the behavior clearly, then inspect the computed styles. Chapter 25, topic 4, example 1.
Example 2: Change one value
Change one important CSS value in the lesson sidebar example for font-style. Predict the visual difference before reloading the page. Chapter 25, topic 4, example 2.
Example 3: Narrow-screen test
Test font-style in the contact form at 320px, 375px, and tablet width. Watch for min-content sizing, unwrapped text, and elements that refuse to shrink. Chapter 25, topic 4, example 3.
Example 4: Translated-text test
Translate the button group into a language with longer labels while using font-style. Confirm buttons, headings, and navigation wrap without widening the page. Chapter 25, topic 4, example 4.
Example 5: Arabic/Persian test
Switch the data table to Arabic or Persian. Verify logical spacing, start/end alignment, sidebar direction, and LTR code islands. Chapter 25, topic 4, example 5.
Example 6: Accessibility test
Check font-style in the media player with keyboard focus, zoom, reduced motion, forced colors, and high text scaling where relevant. Chapter 25, topic 4, example 6.
Example 7: Cascade test
Add a competing rule to the notification and determine why the declaration for font-style wins or loses using the browser's Styles and Computed panels. Chapter 25, topic 4, example 7.
Example 8: Content-stress test
Fill the language selector with very long words, URLs, translated text, images, and nested controls. Adjust font-style without hiding meaningful content. Chapter 25, topic 4, example 8.
Example 9: Refactoring test
Rewrite the course card so font-style uses reusable tokens, logical properties, or a component class while preserving the same behavior. Chapter 25, topic 4, example 9.
Example 10: Production review
Review font-style in the navigation bar for browser support, fallback behavior, RTL, small screens, print, motion preferences, and maintainability. Chapter 25, topic 4, example 10.
CSS/HTML coding example
<!-- HTML -->
<p class="text" lang="en">A long paragraph demonstrates the typography rule in a real content block.</p>
<style>
.text{font-style:italic}
</style>Step-by-step code explanation
- Identify the selector and declaration that demonstrate font-style.
- Read the HTML structure first so you know which box or relationship the CSS is styling.
- The declaration demonstrates font-style on paragraph text.
- Resize the viewport and test long translated content. Confirm that flex/grid items use min-width:0 where needed and that only code or genuinely wide content scrolls locally.
- Switch to Arabic or Persian and verify logical start/end spacing, text alignment, sidebar direction, and LTR isolation for code.
Expected result: The browser visibly demonstrates font-style without requiring the page to exceed the viewport width. If the example contains wide code, only the code block scrolls horizontally. This expected result belongs to Chapter 25, topic 4.
Practice exercise
Build a fresh example for font-style from Chapter 25. Change one value, inspect the computed styles, test at 320px and tablet width, translate the visible text, switch the page to RTL, and explain why the final declaration or layout behavior occurs.
25.5 line-height
line-height is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size. The goal is to connect the syntax to the browser's layout and cascade decisions rather than memorize a property name.
For line-height in Chapter 25, inspect the matched selector, computed value, containing block or formatting context, intrinsic size, and any min/max constraints. When translation is enabled, also inspect whether longer text or RTL direction changes the available inline space.
Start with one small example for line-height, resize the viewport, increase text size, translate the label, and add a competing rule. This shows whether the technique remains predictable under real content rather than only in a fixed desktop mockup. This explanation is specific to Chapter 25, topic 5.
Concept in plain language
line-height is part of the CSS system covered in Chapter 25. The key is to understand what box, selector, cascade rule, layout algorithm, or user preference the declaration affects, then test the result at more than one viewport size.
10 teaching examples
Example 1: Smallest useful case
Build a minimal button group for line-height. Keep only the declarations needed to see the behavior clearly, then inspect the computed styles. Chapter 25, topic 5, example 1.
Example 2: Change one value
Change one important CSS value in the data table example for line-height. Predict the visual difference before reloading the page. Chapter 25, topic 5, example 2.
Example 3: Narrow-screen test
Test line-height in the media player at 320px, 375px, and tablet width. Watch for min-content sizing, unwrapped text, and elements that refuse to shrink. Chapter 25, topic 5, example 3.
Example 4: Translated-text test
Translate the notification into a language with longer labels while using line-height. Confirm buttons, headings, and navigation wrap without widening the page. Chapter 25, topic 5, example 4.
Example 5: Arabic/Persian test
Switch the language selector to Arabic or Persian. Verify logical spacing, start/end alignment, sidebar direction, and LTR code islands. Chapter 25, topic 5, example 5.
Example 6: Accessibility test
Check line-height in the course card with keyboard focus, zoom, reduced motion, forced colors, and high text scaling where relevant. Chapter 25, topic 5, example 6.
Example 7: Cascade test
Add a competing rule to the navigation bar and determine why the declaration for line-height wins or loses using the browser's Styles and Computed panels. Chapter 25, topic 5, example 7.
Example 8: Content-stress test
Fill the article with very long words, URLs, translated text, images, and nested controls. Adjust line-height without hiding meaningful content. Chapter 25, topic 5, example 8.
Example 9: Refactoring test
Rewrite the profile panel so line-height uses reusable tokens, logical properties, or a component class while preserving the same behavior. Chapter 25, topic 5, example 9.
Example 10: Production review
Review line-height in the search form for browser support, fallback behavior, RTL, small screens, print, motion preferences, and maintainability. Chapter 25, topic 5, example 10.
CSS/HTML coding example
<!-- HTML -->
<p class="text" lang="en">A long paragraph demonstrates the typography rule in a real content block.</p>
<style>
.text{line-height:1.8}
</style>Step-by-step code explanation
- Identify the selector and declaration that demonstrate line-height.
- Read the HTML structure first so you know which box or relationship the CSS is styling.
- The declaration demonstrates line-height on paragraph text.
- Resize the viewport and test long translated content. Confirm that flex/grid items use min-width:0 where needed and that only code or genuinely wide content scrolls locally.
- Switch to Arabic or Persian and verify logical start/end spacing, text alignment, sidebar direction, and LTR isolation for code.
Expected result: The browser visibly demonstrates line-height without requiring the page to exceed the viewport width. If the example contains wide code, only the code block scrolls horizontally. This expected result belongs to Chapter 25, topic 5.
Practice exercise
Build a fresh example for line-height from Chapter 25. Change one value, inspect the computed styles, test at 320px and tablet width, translate the visible text, switch the page to RTL, and explain why the final declaration or layout behavior occurs.
Chapter 25 review — 10 questions and answers
1. What should you inspect first when font-family does not work as expected?
Answer: Inspect the matched rules, computed value, box size, layout context, and inherited values for font-family. Then reduce the example until the winning declaration is clear.
2. How should font-family be checked before publishing?
Answer: Test font-family on narrow and wide screens, with long translated text, at increased zoom, and in RTL where direction can affect layout. Add a fallback if browser support or user preferences require one.
3. What should you inspect first when font-size does not work as expected?
Answer: Inspect the matched rules, computed value, box size, layout context, and inherited values for font-size. Then reduce the example until the winning declaration is clear.
4. How should font-size be checked before publishing?
Answer: Test font-size on narrow and wide screens, with long translated text, at increased zoom, and in RTL where direction can affect layout. Add a fallback if browser support or user preferences require one.
5. What should you inspect first when font-weight does not work as expected?
Answer: Inspect the matched rules, computed value, box size, layout context, and inherited values for font-weight. Then reduce the example until the winning declaration is clear.
6. How should font-weight be checked before publishing?
Answer: Test font-weight on narrow and wide screens, with long translated text, at increased zoom, and in RTL where direction can affect layout. Add a fallback if browser support or user preferences require one.
7. What should you inspect first when font-style does not work as expected?
Answer: Inspect the matched rules, computed value, box size, layout context, and inherited values for font-style. Then reduce the example until the winning declaration is clear.
8. How should font-style be checked before publishing?
Answer: Test font-style on narrow and wide screens, with long translated text, at increased zoom, and in RTL where direction can affect layout. Add a fallback if browser support or user preferences require one.
9. What should you inspect first when line-height does not work as expected?
Answer: Inspect the matched rules, computed value, box size, layout context, and inherited values for line-height. Then reduce the example until the winning declaration is clear.
10. How should line-height be checked before publishing?
Answer: Test line-height on narrow and wide screens, with long translated text, at increased zoom, and in RTL where direction can affect layout. Add a fallback if browser support or user preferences require one.