Web Interface Design

Overview

Design exists to separate the primary from the secondary. Users should instantly recognize what matters. Good interface design is invisible—users accomplish goals without noticing the interface.

This skill orchestrates domain-specific reference files. Read only what you need for the task.

Reference File Index

Task	Load Reference
Font sizes, line spacing, heading hierarchy, vertical rhythm	references/typography.md
Input fields, validation, checkboxes, radios, selects, textareas	references/forms-and-inputs.md
Button hierarchy, sizing, states, CTAs, ghost buttons	references/buttons.md
Color palettes, dark mode, tints/shades, state colors	references/color-systems.md
Navigation, cards, tabs, accordions, modals, tables, toasts	references/ui-components.md
Grids, spacing scales, responsive patterns, whitespace	references/layout-and-spacing.md
Focus techniques, hierarchy principles, action pyramid	references/visual-hierarchy.md
Contrast ratios, focus states, screen readers, WCAG	references/accessibility.md
CSS implementation patterns, variables, common styles	references/css-patterns.md

Quick Decision: Which Reference?

What's the problem?
├─ Text hard to read, spacing feels off → typography.md
├─ Form not working well, validation issues → forms-and-inputs.md
├─ Users don't know what to click → buttons.md OR visual-hierarchy.md
├─ Colors look wrong, dark mode broken → color-systems.md
├─ Need nav/cards/tabs/modals/tables → ui-components.md
├─ Spacing inconsistent, layout cramped → layout-and-spacing.md
├─ Everything competes for attention → visual-hierarchy.md
├─ Accessibility audit or contrast issues → accessibility.md
└─ Need CSS implementation → css-patterns.md

Universal Quick Reference

Spacing Scale (4px base)

4, 8, 12, 16, 20, 24, 32, 40, 48, 64, 80, 96

Typography Baseline

• Body: 16px, line-height 1.5
• Heading:body ratio max 1:3 (48px heading for 16px body)
• Paragraph spacing: line-height ÷ 1.5

Touch Targets

• Minimum: 44×44px
• Recommended: 48×48px

Contrast Minimums (WCAG)

• Normal text: 4.5:1
• Large text (18px+ or 14px+ bold): 3:1
• UI components: 3:1

Button Hierarchy

Level	Use For	Treatment
Primary	Main action (ONE per view)	Solid fill, high contrast
Secondary	Alternative actions	Outlined or subtle fill
Tertiary	Minor actions	Text-only or ghost

Dark Mode Essentials

• Background: #121212 (not pure black)
• Text: #E0E0E0 (not pure white)
• Reduce color saturation

Common Mistakes Checklist

• Multiple primary buttons per view
• Placeholder used as only label
• Pure white on pure black
• Thin/light font weights
• Color-only error indicators
• Long centered text
• Inconsistent spacing values

Design Review Protocol

1. Hierarchy: Is primary action obvious? Can you tell what matters?
2. Readability: Text contrast OK? Line length reasonable (45-75 chars)?
3. Forms: Labels above fields? Touch targets 44px+? Helpful errors?
4. Spacing: Consistent scale? Breathing room around elements?
5. Accessibility: Color not sole indicator? Focus states visible?

When NOT to Use This Skill

• Pure visual branding/identity work
• Marketing copy decisions
• Backend architecture
• Mobile native patterns (iOS/Android differ)

Sources

• Web Interface Handbook by Aleksei Baranov (Imperavi)
• User Interface Typography by Imperavi
• Refactoring UI by Wathan & Schoger
• WCAG 2.1 accessibility guidelines