Material Design 3 Layout and Size Hierarchy

Overview

This skill guides the implementation of Material Design 3 (M3) Expressive layout and spacing principles to create clear, organized, and responsive interfaces.

Keywords: Material Design 3, M3, layout, spacing, grid, responsive design, breakpoints, size hierarchy, elevation, padding, margin

Core Principles

Layout Philosophy

M3 layout — from Material You foundations to M3 Expressive — focuses on:

1. Clear Hierarchy: Size and spacing create visual importance
2. Responsive Adaptability: Layouts work across all screen sizes
3. Strategic Spacing: Consistent spacing creates rhythm and flow
4. Size-Based Emphasis: Larger elements naturally draw attention
5. Elevation Depth: Layered surfaces show relationships
6. Explicit and Implicit Containment: Visual grouping through both borders and proximity
7. Background Blur and Layering: Depth effects that guide focus (M3 Expressive)

Spacing Scale System

M3 uses a consistent 4dp spacing scale for all layout spacing:

Base Scale (Increments of 4dp)

:root {
  /* Spacing scale */
  --md-sys-spacing-0: 0px;
  --md-sys-spacing-1: 4px;
  --md-sys-spacing-2: 8px;
  --md-sys-spacing-3: 12px;
  --md-sys-spacing-4: 16px;
  --md-sys-spacing-5: 20px;
  --md-sys-spacing-6: 24px;
  --md-sys-spacing-7: 28px;
  --md-sys-spacing-8: 32px;
  --md-sys-spacing-9: 36px;
  --md-sys-spacing-10: 40px;
  --md-sys-spacing-12: 48px;
  --md-sys-spacing-14: 56px;
  --md-sys-spacing-16: 64px;
  --md-sys-spacing-20: 80px;
  --md-sys-spacing-24: 96px;
}

Semantic Spacing

Define semantic spacing for common patterns:

:root {
  /* Component spacing */
  --md-sys-spacing-component-gap: var(--md-sys-spacing-2); /* 8px */
  --md-sys-spacing-component-padding: var(--md-sys-spacing-4); /* 16px */
  
  /* Layout spacing */
  --md-sys-spacing-section-gap: var(--md-sys-spacing-6); /* 24px */
  --md-sys-spacing-page-margin: var(--md-sys-spacing-4); /* 16px */
  
  /* List spacing */
  --md-sys-spacing-list-item-gap: var(--md-sys-spacing-2); /* 8px */
  --md-sys-spacing-list-padding: var(--md-sys-spacing-4); /* 16px */
}

Responsive Grid System

Breakpoints

M3 defines standard breakpoints for responsive design:

:root {
  /* Breakpoints */
  --md-sys-breakpoint-xs: 0px;      /* Extra small (phones) */
  --md-sys-breakpoint-sm: 600px;    /* Small (tablets portrait) */
  --md-sys-breakpoint-md: 905px;    /* Medium (tablets landscape) */
  --md-sys-breakpoint-lg: 1240px;   /* Large (laptops) */
  --md-sys-breakpoint-xl: 1440px;   /* Extra large (desktops) */
}

Grid Columns

Mobile (0-599px):

• Columns: 4
• Margin: 16px
• Gutter: 16px

Tablet (600-904px):

• Columns: 8
• Margin: 24px
• Gutter: 24px

Desktop (905px+):

• Columns: 12
• Margin: 24px
• Gutter: 24px

CSS Grid Implementation

.layout-grid {
  display: grid;
  gap: var(--md-sys-spacing-4);
  padding: var(--md-sys-spacing-4);
  
  /* Mobile: 4 columns */
  grid-template-columns: repeat(4, 1fr);
}

@media (min-width: 600px) {
  .layout-grid {
    gap: var(--md-sys-spacing-6);
    padding: var(--md-sys-spacing-6);
    /* Tablet: 8 columns */
    grid-template-columns: repeat(8, 1fr);
  }
}

@media (min-width: 905px) {
  .layout-grid {
    /* Desktop: 12 columns */
    grid-template-columns: repeat(12, 1fr);
  }
}

Component Spacing

Buttons

Padding:

• Horizontal: 24px
• Vertical: 10px
• Minimum height: 40px
• Gap between icon and text: 8px

.button {
  padding: var(--md-sys-spacing-2) var(--md-sys-spacing-6);
  min-height: 40px;
  gap: var(--md-sys-spacing-2);
}

Cards

Padding:

• Standard: 16px all sides
• Large cards: 24px all sides
• Compact: 12px all sides

Spacing between elements:

• Header to content: 8px
• Content to actions: 16px
• Between actions: 8px

.card {
  padding: var(--md-sys-spacing-4);
  display: flex;
  flex-direction: column;
  gap: var(--md-sys-spacing-2);
}

.card-actions {
  margin-top: var(--md-sys-spacing-4);
  display: flex;
  gap: var(--md-sys-spacing-2);
}

Dialogs

Padding:

• All sides: 24px
• Content padding: 16px
• Title to content: 16px
• Content to actions: 24px

Sizing:

• Min width: 280px
• Max width: 560px
• Mobile: Full width with margin

.dialog {
  padding: var(--md-sys-spacing-6);
  min-width: 280px;
  max-width: 560px;
  display: flex;
  flex-direction: column;
  gap: var(--md-sys-spacing-4);
}

@media (max-width: 599px) {
  .dialog {
    width: calc(100% - 32px);
    margin: var(--md-sys-spacing-4);
  }
}

Lists

Spacing:

• Between list items: 0px (items touch)
• Item padding: 16px horizontal, 8px vertical
• Icon to text: 16px
• Text to secondary action: 16px

.list-item {
  padding: var(--md-sys-spacing-2) var(--md-sys-spacing-4);
  display: flex;
  align-items: center;
  gap: var(--md-sys-spacing-4);
  min-height: 56px;
}

Navigation

App Bar:

• Height: 64px (desktop), 56px (mobile)
• Padding: 16px horizontal
• Gap between items: 24px

Navigation Rail:

• Width: 80px
• Item height: 56px
• Item spacing: 4px

Bottom Navigation:

• Height: 80px
• Item width: Equal distribution
• Icon to label: 4px

.app-bar {
  height: 56px;
  padding: 0 var(--md-sys-spacing-4);
  display: flex;
  align-items: center;
  gap: var(--md-sys-spacing-6);
}

@media (min-width: 600px) {
  .app-bar {
    height: 64px;
  }
}

Size Hierarchy

Use Size for Emphasis

M3 Expressive uses size strategically to create visual hierarchy:

Hero Elements (Largest):

• 2-3x larger than standard
• Use for main call-to-action or featured content
• Limited to 1-2 per view

Primary Elements (Large):

• 1.5x larger than standard
• Main content, featured items
• 3-5 per view

Standard Elements (Base):

• Default size for most content
• Maintains readability and usability

Secondary Elements (Small):

• 0.75x of standard
• Supporting information, metadata
• Can be numerous

Tertiary Elements (Smallest):

• 0.5x of standard
• Timestamps, captions, fine print
• Use sparingly

Size Examples

/* Hero button */
.button-hero {
  padding: var(--md-sys-spacing-4) var(--md-sys-spacing-10);
  min-height: 56px;
  font-size: 18px;
}

/* Standard button */
.button-standard {
  padding: var(--md-sys-spacing-2) var(--md-sys-spacing-6);
  min-height: 40px;
  font-size: 14px;
}

/* Small button */
.button-small {
  padding: var(--md-sys-spacing-1) var(--md-sys-spacing-4);
  min-height: 32px;
  font-size: 12px;
}

Elevation System

M3 uses elevation to show depth and hierarchy:

Elevation Levels

Level 0 (On surface):

• No shadow
• Background elements

Level 1 (Slight elevation):

• Shadow: 0 1px 2px rgba(0,0,0,0.3), 0 1px 3px rgba(0,0,0,0.15)
• Cards, list items
• Use: 1dp

Level 2 (Elevated):

• Shadow: 0 2px 4px rgba(0,0,0,0.3), 0 3px 4px rgba(0,0,0,0.15)
• Raised buttons, FABs at rest
• Use: 3dp

Level 3 (Floating):

• Shadow: 0 4px 8px rgba(0,0,0,0.3), 0 6px 8px rgba(0,0,0,0.15)
• FABs on hover, app bars
• Use: 6dp

Level 4 (Modal):

• Shadow: 0 8px 12px rgba(0,0,0,0.3), 0 12px 16px rgba(0,0,0,0.15)
• Dialogs, navigation drawer
• Use: 8dp

Level 5 (High modal):

• Shadow: 0 12px 16px rgba(0,0,0,0.3), 0 16px 24px rgba(0,0,0,0.15)
• Modal bottom sheets
• Use: 12dp

Elevation Tokens

:root {
  --md-sys-elevation-0: none;
  --md-sys-elevation-1: 0 1px 2px rgba(0,0,0,0.3), 0 1px 3px rgba(0,0,0,0.15);
  --md-sys-elevation-2: 0 2px 4px rgba(0,0,0,0.3), 0 3px 4px rgba(0,0,0,0.15);
  --md-sys-elevation-3: 0 4px 8px rgba(0,0,0,0.3), 0 6px 8px rgba(0,0,0,0.15);
  --md-sys-elevation-4: 0 8px 12px rgba(0,0,0,0.3), 0 12px 16px rgba(0,0,0,0.15);
  --md-sys-elevation-5: 0 12px 16px rgba(0,0,0,0.3), 0 16px 24px rgba(0,0,0,0.15);
}

Elevation with Tinting

M3 adds a subtle color tint to elevated surfaces:

.elevated-surface {
  background-color: var(--md-sys-color-surface);
  box-shadow: var(--md-sys-elevation-1);
  /* Add subtle tint using primary color */
  background-image: linear-gradient(
    rgba(var(--md-sys-color-primary-rgb), 0.05),
    rgba(var(--md-sys-color-primary-rgb), 0.05)
  );
}

Responsive Layout Patterns

Mobile-First Approach

Start with mobile layout, then enhance for larger screens:

/* Mobile: Stack vertically */
.content-layout {
  display: flex;
  flex-direction: column;
  gap: var(--md-sys-spacing-4);
  padding: var(--md-sys-spacing-4);
}

/* Tablet: Two columns */
@media (min-width: 600px) {
  .content-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--md-sys-spacing-6);
    padding: var(--md-sys-spacing-6);
  }
}

/* Desktop: Three columns with sidebar */
@media (min-width: 905px) {
  .content-layout {
    grid-template-columns: 250px 1fr 1fr;
  }
}

Container Queries

Use for component-level responsiveness:

.card-container {
  container-type: inline-size;
}

.card {
  display: flex;
  flex-direction: column;
}

@container (min-width: 400px) {
  .card {
    flex-direction: row;
    gap: var(--md-sys-spacing-4);
  }
}

Common Layout Patterns

Centered Content:

.centered-layout {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--md-sys-spacing-6);
}

Sidebar Layout:

.sidebar-layout {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: var(--md-sys-spacing-6);
}

@media (max-width: 904px) {
  .sidebar-layout {
    grid-template-columns: 1fr;
  }
}

Dashboard Grid:

.dashboard-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--md-sys-spacing-4);
}

Containment Principles

Explicit Containment

Use visible boundaries to group related content:

/* Card containment with outline */
.contained-group {
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--md-sys-shape-corner-medium);
  padding: var(--md-sys-spacing-4);
  background: var(--md-sys-color-surface-container);
}

/* Elevated containment */
.elevated-group {
  box-shadow: var(--md-sys-elevation-1);
  border-radius: var(--md-sys-shape-corner-medium);
  padding: var(--md-sys-spacing-4);
  background: var(--md-sys-color-surface-container-low);
}

Implicit Containment

Use proximity, open space, and alignment to group items without visible borders:

/* Implicit grouping through proximity */
.implicit-group {
  display: flex;
  flex-direction: column;
  gap: var(--md-sys-spacing-1); /* Tight spacing implies grouping */
}

/* Separated groups use larger spacing */
.section-gap {
  margin-bottom: var(--md-sys-spacing-8); /* Larger gap separates groups */
}

When to Use Each

Containment Type	Use When
Explicit (borders/cards)	Interactive content, distinct sections, actionable groups
Explicit (elevation)	Content that needs to feel "lifted" or modal
Implicit (proximity)	Related text blocks, label-value pairs, sequential content
Implicit (alignment)	Grid layouts, navigation items, consistent structure

Background Blur and Depth Effects

M3 Expressive introduces background blur and layering for improved depth and focus:

Background Blur

Strategic blur behind overlays, modals, and navigation elements:

/* Blur behind modal dialogs */
.dialog-backdrop {
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background-color: rgba(0, 0, 0, 0.32);
}

/* Blur behind floating toolbars */
.floating-toolbar {
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: rgba(var(--md-sys-color-surface-rgb), 0.85);
}

/* Blur behind navigation drawers */
.nav-drawer-scrim {
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  background-color: var(--md-sys-color-scrim);
  opacity: 0.32;
}

When to Use Blur

1. Behind modals and dialogs: Creates focus on foreground content
2. Behind floating toolbars: Separates toolbar from content without heavy elevation
3. Behind navigation drawers: Softens the transition between drawer and content
4. Behind bottom sheets: Creates depth without fully obscuring content
5. Never on content itself: Blur is for scrims and backgrounds, not readable content

Depth Layering

Combine elevation, blur, and surface tinting for clear layering:

/* Layer 1: Base content */
.base-layer {
  background: var(--md-sys-color-surface);
}

/* Layer 2: Elevated content */
.elevated-layer {
  background: var(--md-sys-color-surface-container);
  box-shadow: var(--md-sys-elevation-1);
}

/* Layer 3: Overlay with blur */
.overlay-layer {
  backdrop-filter: blur(16px);
  background: rgba(var(--md-sys-color-surface-container-high-rgb), 0.9);
  box-shadow: var(--md-sys-elevation-3);
}

Interaction States

M3 defines consistent interaction states for all interactive elements:

State Layer System

State layers are overlays using the content color at specific opacities:

State	Opacity	Description
Enabled	0%	Default, no overlay
Hovered	8%	Pointer device hover
Focused	12%	Keyboard/accessibility focus
Pressed	12%	Touch/click press
Dragged	16%	Active drag operation
Disabled	0%	Non-interactive (content at 38%, background at 12%)

/* State layer implementation */
.interactive-element {
  position: relative;
}

.interactive-element::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: var(--md-sys-color-on-surface);
  opacity: 0;
  transition: opacity 200ms var(--md-sys-motion-easing-standard);
  pointer-events: none;
}

.interactive-element:hover::before { opacity: 0.08; }
.interactive-element:focus-visible::before { opacity: 0.12; }
.interactive-element:active::before { opacity: 0.12; }

/* Disabled state */
.interactive-element:disabled {
  opacity: 0.38;
  pointer-events: none;
}

.interactive-element:disabled::before {
  opacity: 0;
}

State Priority

Only one state layer is visually applied at a time. Priority order:

1. Dragged (highest)
2. Pressed
3. Focused
4. Hovered
5. Enabled (lowest)

Touch Targets and Accessibility

Minimum Touch Target Size

All interactive elements must be at least 48×48dp:

.touch-target {
  min-width: 48px;
  min-height: 48px;
  /* Visual size can be smaller with padding */
  padding: var(--md-sys-spacing-3);
}

Focus Indicators

Ensure adequate spacing for focus rings:

.focusable {
  position: relative;
}

.focusable:focus-visible {
  outline: 2px solid var(--md-sys-color-primary);
  outline-offset: 2px;
}

Best Practices

Do's

1. ✅ Use the 4dp spacing scale consistently
2. ✅ Define semantic spacing tokens for common patterns
3. ✅ Start mobile-first, then enhance for larger screens
4. ✅ Use size hierarchy to create visual emphasis
5. ✅ Maintain minimum 48×48dp touch targets
6. ✅ Use elevation to show component relationships
7. ✅ Test layouts at all breakpoints
8. ✅ Use CSS Grid and Flexbox for modern layouts

Don'ts

1. ❌ Don't use arbitrary spacing values (stick to the scale)
2. ❌ Don't make layouts that only work on desktop
3. ❌ Don't use tiny touch targets on mobile
4. ❌ Don't overuse elevation (creates visual noise)
5. ❌ Don't ignore container queries for components
6. ❌ Don't create fixed-width layouts without max-width
7. ❌ Don't forget horizontal scrolling on mobile

Performance Considerations

1. Use CSS Grid/Flexbox: Avoid float-based layouts
2. Minimize Layout Shifts: Define dimensions to prevent CLS
3. Optimize Images: Use responsive images with srcset
4. Lazy Load: Defer off-screen content
5. Container Queries: Better than media queries for components

Checklist for Layout Implementation

When implementing M3 layout, ensure:

• Spacing scale is defined (4dp increments)
• Semantic spacing tokens are created
• Breakpoints are defined (600px, 905px, 1240px)
• Mobile-first responsive approach is used
• Grid system supports 4/8/12 columns
• Touch targets are minimum 48×48dp
• Elevation system is defined (5 levels)
• Size hierarchy is used for emphasis
• All spacing uses tokens (no hard-coded values)
• Layouts work on all screen sizes
• Focus indicators have adequate spacing
• Container queries are used for components
• Maximum content width is set for readability
• Elevation tinting is applied to raised surfaces
• Containment principles are applied (explicit and implicit grouping)
• Background blur is used for modals, drawers, and floating elements
• Interaction states are implemented with correct opacity values
• Disabled states use 38% content opacity and 12% background opacity
• State layers use on-surface color at appropriate opacities
• Performance is optimized (Grid/Flexbox, lazy loading)

Resources

• M3 layout overview: https://m3.material.io/foundations/layout/understanding-layout/overview
• Material Design Tokens: https://github.com/material-foundation/material-tokens