Web Design Patterns

CSS implementation patterns for production-grade interfaces. For design fundamentals and decision-making, see ui-design. This skill focuses on code.

See also: ui-design for typography/color/spacing theory, frontend-design for creative aesthetics.

Installation

OpenClaw / Moltbot / Clawbot

npx clawhub@latest install web-design

Layout Principles

Use CSS Grid for two-dimensional layouts and Flexbox for one-dimensional flow. Choose the right tool for each context.

Layout Need	Tool	Why
Page-level structure	CSS Grid (`grid-template-areas`)	Named regions, explicit row/column control
Navigation bars	Flexbox	Single-axis alignment, spacing with `gap`
Card grids	Grid (`auto-fill` / `auto-fit`)	Responsive without media queries
Centering	Grid (`place-items: center`)	Shortest, most reliable centering
Sidebar + content	Grid (`grid-template-columns: 250px 1fr`)	Proportional sizing with fixed sidebar
Stacking overlaps	Grid + `grid-area: 1/1`	Layer elements without `position: absolute`

Spatial Composition

Go beyond predictable layouts. Intentional asymmetry, overlapping elements, and grid-breaking accents create visual interest. Use grid stacking (grid-area: 1/1) instead of position: absolute for overlapping elements. Choose generous negative space for luxury/editorial aesthetics, or controlled density for data-rich interfaces — the choice must be intentional.

Typography

Typography carries 90% of a design's personality. Choose fonts that match the interface's purpose.

Context	Display Font Direction	Body Font Direction	Example Pairing
Editorial / magazine	High-contrast serif	Neutral humanist sans	Playfair Display + Source Sans 3
SaaS dashboard	Geometric sans	Matching weight sans	DM Sans + DM Mono (data)
Creative portfolio	Expressive display	Clean readable sans	Syne + Outfit
E-commerce luxury	Thin modern serif	Elegant sans	Cormorant Garamond + Jost
Developer tooling	Monospace display	Monospace body	JetBrains Mono + IBM Plex Mono

Type Scale

Use a consistent ratio. A 1.25 (major third) scale works for most interfaces: text-xs 0.64rem, text-sm 0.8rem, text-base 1rem, text-lg 1.25rem, text-xl 1.563rem, text-2xl 1.953rem, text-3xl 2.441rem, text-4xl 3.052rem. Set body text to 1rem (16px minimum), line-height 1.5 for body, 1.1–1.2 for headings. Limit line length to 60–75ch.

Color

Building a Palette

Every palette needs five functional roles:

Role	Purpose	Example Usage
Primary	Brand identity, primary actions	Buttons, links, active states
Neutral	Text, borders, backgrounds	Body text, cards, dividers
Accent	Secondary actions, highlights	Tags, badges, secondary buttons
Success / Warning / Error	Semantic feedback	Toasts, form validation, status
Surface	Layered backgrounds	Cards on page, modals on overlay

Contrast and Depth

Create depth through surface layering, not just shadows:

:root {
  --surface-0: hsl(220 15% 8%);    /* page background */
  --surface-1: hsl(220 15% 12%);   /* card */
  --surface-2: hsl(220 15% 16%);   /* raised element */
  --surface-3: hsl(220 15% 20%);   /* popover / modal */
}

Use HSL or OKLCH for perceptually uniform color manipulation. Dominant color with sharp accents outperforms evenly-distributed palettes. Always verify WCAG contrast: 4.5:1 for normal text, 3:1 for large text.

Spacing

Consistent spacing creates rhythm. Use an 8px base unit (or 4px for dense UIs):

Token	Value	Use
`--space-1`	0.25rem (4px)	Inline icon gaps, tight padding
`--space-2`	0.5rem (8px)	Input padding, compact lists
`--space-3`	0.75rem (12px)	Button padding, card inner spacing
`--space-4`	1rem (16px)	Default element spacing
`--space-6`	1.5rem (24px)	Section padding, card gaps
`--space-8`	2rem (32px)	Section separation
`--space-12`	3rem (48px)	Major section breaks
`--space-16`	4rem (64px)	Page-level vertical rhythm

Apply spacing consistently: use gap on Grid/Flexbox containers instead of margins on children. This eliminates margin-collapse bugs and simplifies responsive adjustments.

Visual Hierarchy

Guide the eye through deliberate contrast in size, weight, color, and space.

Hierarchy Techniques

Technique	How	Impact
Size contrast	Hero heading 3–4x body size	Immediate focal point
Weight contrast	Bold headings + regular body	Scannability
Color contrast	Primary text vs muted secondary	Information layering
Spatial grouping	Tight spacing within groups, wide between	Gestalt proximity
Elevation	Shadows / surface layers	Interactive affordance
Whitespace isolation	Empty space around key element	Emphasis through absence

Practical Pattern — Card Hierarchy

Layer hierarchy within cards: eyebrow (xs, uppercase, muted) → title (xl, semibold) → body (base, secondary color, 1.6 line-height) → action (spaced apart with margin-top). Use surface color for separation and consistent padding from spacing tokens.

Responsive Design

Breakpoint Strategy

Breakpoint	Target	Approach
`< 640px`	Mobile	Single column, stacked navigation, touch targets ≥ 44px
`640–1024px`	Tablet	Two-column options, collapsible sidebars
`1024–1440px`	Desktop	Full layout, hover interactions enabled
`> 1440px`	Wide	Max-width container (1280px), prevent ultra-wide line lengths

Fluid Techniques

Prefer fluid sizing over rigid breakpoints where possible:

/* Fluid typography — scales between 640px and 1440px viewport */
h1 { font-size: clamp(2rem, 1.5rem + 2.5vw, 3.5rem); }

/* Fluid spacing */
section { padding-block: clamp(2rem, 1rem + 4vw, 6rem); }

/* Intrinsic grid — no media queries needed */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 20rem), 1fr)); gap: var(--space-6); }

Use container queries (@container) for component-level responsiveness when a component's layout should respond to its container, not the viewport.

Accessibility

Accessibility is not optional. Build it in from the start.

Requirement	Implementation	Standard
Color contrast	4.5:1 normal text, 3:1 large text / UI	WCAG 2.1 AA
Keyboard navigation	All interactive elements focusable and operable	WCAG 2.1.1
Focus indicators	Visible `:focus-visible` ring, 2px+ offset	WCAG 2.4.7
Semantic HTML	Use `<button>`, `<nav>`, `<main>`, `<article>` etc.	WCAG 1.3.1
Alt text	Descriptive for informational images, `alt=""` for decorative	WCAG 1.1.1
Motion safety	Respect `prefers-reduced-motion`	WCAG 2.3.3
Touch targets	Minimum 44×44px interactive areas	WCAG 2.5.8
ARIA when needed	`aria-label`, `aria-live`, `role` only when native semantics insufficient	WCAG 4.1.2

/* Robust focus indicator */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Respect motion preferences */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

Component Design

Anatomy of a Well-Designed Component

Every UI component should have clear states, consistent spacing, and predictable behavior:

State	Visual Treatment	Example
Default	Base styling	Button at rest
Hover	Subtle shift — background, shadow, or scale	`background` lightens 5-10%
Active / Pressed	Compressed feel — reduced shadow, slight inset	`transform: scale(0.98)`
Focus	High-visibility ring, no outline removal	`:focus-visible` ring
Disabled	Reduced opacity, `cursor: not-allowed`	`opacity: 0.5`
Loading	Spinner or skeleton, disabled interaction	Inline spinner replacing label

Design Token Architecture

Structure tokens in three layers for maintainability:

/* Layer 1: Primitive values */
--blue-500: oklch(0.55 0.2 250);
--gray-100: oklch(0.95 0.005 250);
--radius-md: 0.5rem;

/* Layer 2: Semantic aliases */
--color-primary: var(--blue-500);
--color-surface: var(--gray-100);
--radius-button: var(--radius-md);

/* Layer 3: Component-specific */
--btn-bg: var(--color-primary);
--btn-radius: var(--radius-button);
--btn-padding: var(--space-2) var(--space-4);

This three-layer approach allows theme switching by remapping Layer 2 without touching components.

Interaction Patterns

Motion and Animation

Use motion to communicate state changes, not to decorate. Focus on high-impact moments:

Interaction	Duration	Easing	Purpose
Button hover	150ms	`ease-out`	Acknowledge interaction
Modal open	250ms	`ease-out`	Draw attention
Modal close	200ms	`ease-in`	Quick dismissal
Page transition	300ms	`ease-in-out`	Maintain spatial context
Stagger reveal	50–80ms delay per item	`ease-out`	Sequential content loading
Micro-feedback	100ms	`ease-out`	Toggle, checkbox, switch

/* Staggered entrance animation */
.stagger-item {
  opacity: 0;
  translate: 0 1rem;
  animation: reveal 0.5s ease-out forwards;
}
.stagger-item:nth-child(1) { animation-delay: 0ms; }
.stagger-item:nth-child(2) { animation-delay: 60ms; }
.stagger-item:nth-child(3) { animation-delay: 120ms; }

@keyframes reveal {
  to { opacity: 1; translate: 0 0; }
}

Scroll-Driven Effects

Use native animation-timeline: scroll() (behind @supports) for parallax and reveal effects without JavaScript. Wrap in feature detection to gracefully degrade.

Design Quality Checklist

Before shipping, verify against these criteria: