UX Typography Skill

Fluid typography system using Utopia scale with container query inline (cqi) units. This skill covers font selection, sizing, and typographic hierarchy.

Font Stack

Display Font (Headings, UI)

--font-display: 'Cinzel', serif;

Use for:

• Headings (h1-h6)
• Navigation labels
• Button text
• Phase names
• Game titles

Body Font (Content, Paragraphs)

--font-sans: 'Crimson Pro', Georgia, serif;

Use for:

• Body text
• Paragraphs
• Form inputs
• Hints and descriptions
• Story content

Fluid Type Scale

The project uses Utopia fluid scale with cqi units (container query inline). Sizes interpolate based on container width.

IMPORTANT: cqi units require container-type: inline-size on an ancestor. The project sets this on html.

Type Steps

Token	Min (320px)	Max (1240px)	Usage
--step--2	11.11px	12.50px	Fine print, captions
--step--1	13.33px	16.67px	Secondary text, hints
--step-0	16px	22.22px	Body text (base)
--step-1	19.20px	29.63px	Large body, subheads
--step-2	23.04px	39.51px	Section headings
--step-3	27.65px	52.68px	Page headings
--step-4	33.18px	70.24px	Hero text
--step-5	39.81px	93.65px	Display, titles

Usage

.body-text {
  font-size: var(--step-0);
  font-family: var(--font-sans);
}

.heading {
  font-size: var(--step-3);
  font-family: var(--font-display);
}

.caption {
  font-size: var(--step--2);
  font-family: var(--font-sans);
}

Line Height

Recommended Values

Content Type	Line Height	Rationale
Headings	1.1–1.2	Tight for visual impact
Body text	1.5–1.6	Optimal readability
UI elements	1.2–1.3	Compact but legible
Long-form	1.6–1.7	Comfortable reading

.heading {
  line-height: 1.1;
}

.body {
  line-height: 1.5;
}

.button-text {
  line-height: 1.2;
}

Letter Spacing

Tokens

:root {
  --letter-spacing-tight: -0.025em;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.025em;
  --letter-spacing-wider: 0.05em;
}

Usage Guidelines

Context	Spacing	Example
Large headings	--letter-spacing-tight	Hero titles
Body text	--letter-spacing-normal	Paragraphs
Small caps	--letter-spacing-wide	Labels
All caps	--letter-spacing-wider	Buttons

.hero-title {
  font-size: var(--step-5);
  letter-spacing: var(--letter-spacing-tight);
}

.phase-label {
  text-transform: uppercase;
  letter-spacing: var(--letter-spacing-wider);
}

Font Weight

Available Weights

• 400 - Regular (body text)
• 600 - Semibold (emphasis, labels)
• 700 - Bold (headings, buttons)

.body {
  font-weight: 400;
}

.label {
  font-weight: 600;
}

.heading {
  font-weight: 700;
}

Typographic Hierarchy

Example Structure

/* Page title */
h1 {
  font-family: var(--font-display);
  font-size: var(--step-4);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: var(--letter-spacing-tight);
}

/* Section heading */
h2 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  font-weight: 600;
  line-height: 1.2;
}

/* Body text */
p {
  font-family: var(--font-sans);
  font-size: var(--step-0);
  font-weight: 400;
  line-height: 1.5;
}

/* Caption/hint */
.hint {
  font-family: var(--font-sans);
  font-size: var(--step--1);
  color: var(--theme-on-surface-variant);
}

Text Styling Patterns

Emphasis

/* Strong emphasis */
strong, .strong {
  font-weight: 600;
}

/* Italic for terms */
em, .term {
  font-style: italic;
}

/* Highlighted text */
mark, .highlight {
  background: var(--theme-primary-container);
  padding-inline: 0.2em;
  border-radius: 2px;
}

Links

a {
  color: var(--theme-primary);
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

a:hover {
  text-decoration-thickness: 2px;
}

a:focus-visible {
  outline: var(--focus-ring-width) solid var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

Keyboard Hints

kbd {
  display: inline-block;
  padding: 0.1em 0.4em;
  font-family: inherit;
  font-size: 0.9em;
  background: var(--theme-surface);
  border: 1px solid var(--theme-outline);
  border-radius: 3px;
}

Responsive Typography

The fluid scale handles most responsiveness automatically. For specific adjustments:

/* Container query for constrained spaces */
@container (max-width: 200px) {
  .phase-label {
    font-size: var(--step--2);
  }
}

/* Override for very large displays */
@container (min-width: 1400px) {
  .hero {
    font-size: var(--step-5);
  }
}

Accessibility

Minimum Sizes

• Body text: --step-0 minimum (16px at base)
• Interactive labels: --step--1 minimum (13px at base)
• Never smaller than --step--2 for any readable text

Avoid

/* DON'T: Fixed pixel sizes */
.bad {
  font-size: 14px;
}

/* DON'T: Viewport units for body text */
.bad {
  font-size: 2vw;
}

/* DON'T: Low contrast with small text */
.bad {
  font-size: var(--step--2);
  color: var(--theme-outline);
}

Do

/* DO: Use fluid tokens */
.good {
  font-size: var(--step-0);
}

/* DO: Ensure contrast for small text */
.good {
  font-size: var(--step--1);
  color: var(--theme-on-surface);
}