The Vue Playbook

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Key aspects of visual elements ​

Visual accessibility ensures that design elements are perceivable and understandable by users with visual impairments. In practice, this means every visual cue – color, images, text layout, etc. – must also be usable by people who cannot rely on vision alone. For example, alternative text allows screen readers to convey image information, and high contrast makes text readable to low-vision users. Below are the critical visual design considerations:

Color and Contrast ​

High contrast and careful use of color are essential for readability. WCAG 2.1 recommends a minimum contrast ratio of 4.5:1 for normal text. This helps users with low vision or color deficiencies see content clearly. In addition, never use color as the sole means of conveying information. Both the WCAG guidelines and practical design guides stress that “color is not the only way of distinguishing information. For instance, required fields or error messages should not be indicated by color alone; include text labels, icons, or shapes as additional cues. Key points:

  • Use sufficient contrast: Ensure text and background colors meet WCAG ratios (≥4.5:1 for body text) so content remains legible.
  • Provide redundant cues: Follow WCAG Success Criterion 1.4.1 (“Use of Color”) by adding shapes, labels, or patterns whenever color conveys meaning. For example, pair a red “required” label with an asterisk and text, not red alone.
  • Test for color blindness: Utilize tools (contrast checkers and color-blindness simulators) to verify that designs are still understandable without color.

Images and Icons ​

All informative images and icons must have meaningful text alternatives. Per WCAG 1.1.1, “images must have text alternatives that describe the information or function”. For decorative images that convey no content, use empty alt (alt="") so screen readers skip them. For example, a photo illustrating an article needs a brief caption-like alt text, whereas a layout graphic with no essential info can be marked decorative. Iconography requires special care:

  • Provide alt text or labels: If an icon is used as a button or link (e.g. a trash-can icon for “delete”), its alt text should convey the icon’s function, not just its appearance. For instance, the alt text for a mail icon linking to contact should be “Email us,” not “envelope“.
  • Use ARIA labels when needed: Icon-only buttons without visible text must have an accessible name. You can use aria-label or aria-labelledby to supply a label that screen readers will announce. For example, a close (×) icon button should have aria-label="Close" so its purpose is clear.
  • Choose clear, familiar icons: Icons should reinforce meaning and be easily understood. Only use icons purposefully (not as mere decoration) and pair them with text labels or tooltips if possible.

Typography ​

Readable text is fundamental. Use legible font sizes and spacing and allow users to adjust text. As a rule of thumb, body text should be at least 16px (or the 1em equivalent), with headings proportionally larger. Avoid very small fonts that strain readers. Line length also matters; keep lines roughly 45–75 characters so readers’ eyes can track easily. Adequate line height (about 1.4–1.6× the font size for body text) prevents lines from appearing cramped.

  • Adjustable text: Ensure your site does not break when text is enlarged. WCAG requires that users can increase text size and line spacing (up to 200% line height, 150% spacing, etc.) without losing content or functionality. In practice, avoid fixed-size elements or content that cannot expand.
  • Font choice: Favor simple, common typefaces with high readability. Sans-serif fonts often work well on screens. Also ensure distinct character shapes (e.g. differentiate “I”/“l”/“1” clearly) to prevent confusion.
  • Spacing: Provide sufficient letter and word spacing. Tight letters can blur together, hindering those with vision or cognitive issues. Good spacing helps each word stand out.

Visual Focus Indicators ​

Keyboard users rely on visual focus cues to navigate. Every interactive element (links, buttons, form fields) must have a highly visible focus indicator. WCAG 2.4.7 specifies that “each item receiving focus must have a visible indicator”. Common techniques include an outline, box shadow, or background-color change on focus. Avoid removing the browser’s default focus outline unless you replace it with something equally obvious For example, when a link is tabbed to, highlight it (often with an outline or color change) so sighted keyboard users immediately see where focus is. This is critical – without it, keyboard navigation is essentially blind.

Layout and Structure ​

A clear, consistent layout helps users find content quickly. Use headings and logical grouping so that the visual hierarchy matches the document structure. WCAG 2.4.6 (Headings and Labels) and 1.3.1 (Info and Relationships) stress that visual order should follow reading order. Key practices include:

  • Consistent headers: Use semantic headings (H1–H6) to define sections. Visually style them (size, weight, color) so they are distinct and indicate importance. This allows screen readers and sighted users alike to scan the page structure.
  • Logical grouping: Place related items close together and in sequence. For example, labels next to their inputs, and form instructions near the relevant fields. Digital.gov advises grouping content so that “related items are in proximity”.
  • Avoid clutter: Keep designs clean. Minimal, intentional layouts make it easier for all users (including those with attention disorders) to focus on what’s important. Ensure that any visual hierarchy (font size, color, spacing) matches the markup hierarchy – heading tags should correspond to the visual headings used.

Animations and Motion ​

Motion can cause problems for many users. Flashing or rapid animations can trigger seizures or migraines, and scrolling effects can provoke vestibular (inner-ear) issues like dizziness. WCAG’s “Three Flashes” criterion warns that “flashing content can cause migraines, dizziness, nausea, and seizures”. To be safe:

  • Limit flashes: Avoid any element flashing more than three times per second. Even bright rapid images (like quick blinking effects) should be eliminated or replaced with non-animated alternatives.
  • Respect motion sensitivity: If your site includes animations or motion (e.g. parallax scrolling, carousels, page transitions), provide an option to disable or pause them. WCAG 2.3.3 (Animation from Interactions) advises allowing users to turn off non-essential motion. For instance, honor the user’s prefers-reduced-motion setting so that those who have motion sensitivity won’t see moving effects.
  • Minimize unnecessary movement: Only animate what’s essential. Unnecessary animation (even background movements or hover effects) should be avoidable. The rationale is that animated content “can be disabled” when it’s non-essential, protecting users prone to motion-triggered discomfort.

Resources for Further Reading ​

In summary, visual accessibility means designing interfaces so that sight-impaired users are not excluded. By ensuring high contrast, meaningful text alternatives, clear typography, obvious focus cues, logical layouts, and safe use of motion, you remove visual barriers and make your content reachable by everyone