/08-use-shadows-appropriately

name: use-shadows-appropriately
description: Add depth only when functionally necessary (elevation, not decoration)
domain: ui-design
skill-type: corrective
version: 1.0.0
author: refactoring-ui-expert
prerequisites: []
dependencies: []

Skill: Use Shadows Appropriately

Purpose

Add depth and elevation only when functionally necessary, avoiding decorative shadows.

Key Fix Applied (from Autoresearch)

Added nuance: Subtle shadows on cards are acceptable (less distracting than borders). Large decorative shadows on static elements are wrong.

Type

Corrective + Evaluative

Input

• UI element inventory
• Element purposes (static, interactive, overlay)
• Current shadow specifications

Output

• Shadow usage recommendations
• Pass/Fail assessment

Transformation Performed

Removes decorative shadows from static elements, reserves shadows for elevation layers (modals above content, dropdowns above page).

Decision Criteria

PASS (Appropriate Shadow Usage)

• **Small shadows on cards** (subtle, less distracting than borders) ✅
• **Modals/dialogs**: Large shadow (elevated above all content)
• **Dropdowns/menus**: Medium shadow (above page, below modals)
• **Cards**: Subtle or no shadow (flat design preferred)
• **Hover states**: Subtle shadow increase (affordance for clickability)
• **Static elements**: No shadow
• Consistent shadow system (2-3 levels max)

FAIL (Inappropriate Shadow Usage)

• **Large decorative shadows on static cards**
• Heavy shadows on static content
• Inconsistent shadow values
• Decorative shadows that don't indicate elevation
• Shadows on text or icons

Nuance (Key Insight)

Subtle shadows (small blur, low opacity) on cards are OK. The book recommends them as alternative to borders. Large, flashy shadows on static content are wrong.

Shadow Elevation Scale

| Level | Use Case | CSS Example (approximate) | |-------|----------|---------------------------| | **None** | Static content, text, icons | `none` | | **Subtle** | Cards (alternative to borders) | `0 2px 4px rgba(0,0,0,0.1)` | | **Low** | Raised cards, buttons | `0 4px 6px rgba(0,0,0,0.1)` | | **Medium** | Dropdowns, popovers, tooltips | `0 10px 15px rgba(0,0,0,0.1)` | | **High** | Modals, dialogs, drawers | `0 20px 25px rgba(0,0,0,0.15)` |

Shadow Principles

1. **Shadows indicate elevation** - Higher = closer to user 2. **Shadows indicate interactivity** - Clickable things can have shadow 3. **Shadows separate layers** - Modal casts shadow on page behind it 4. **Shadows should be subtle** - Good shadows are barely noticeable 5. **Consistency matters** - Same elevation = same shadow

Common Failure Modes

| Failure | Description | Fix | |---------|-------------|-----| | **Shadow Carpet** | Every card has a shadow | Flatten static cards, subtle shadows OK | | **Drop Shadow Abuse** | Heavy shadows on static elements | Reserve for elevation/interaction | | **Inconsistent Depth** | Similar elements different shadows | Create 2-3 shadow levels, apply consistently | | **Black Shadows** | Pure black shadows (harsh) | Use rgba with low opacity, tinted to brand | | **No Modal Separation** | Modal doesn't feel above page | Increase shadow spread and blur |

Prerequisites

• Visual hierarchy established
• Understanding of which elements are interactive

Dependencies

• `eliminate-visual-clutter` (shadows often add clutter)

Refactoring UI References

• "Use shadows to convey elevation"
• "Use a box shadow instead of hard borders - subtle shadows outline effectively without visual clutter"
• "Shadows should be subtle"

Example Assessment

**Input:** Page with card shadows (`0 4px 6px rgba(0,0,0,0.1)`), button shadows (`0 2px 4px`), modal shadow (`0 4px 6px`), text with text-shadow

**Evaluation:** FAIL (cluttered)

• Cards don't need shadows (static content)
• Modal shadow same as cards (should be higher)
• Text shadow decorative

**Recommendation:**

• Remove card shadows OR use subtle (`0 2px 4px`)
• Remove text shadow
• Modal: `0 20px 25px rgba(0,0,0,0.15)`
• Buttons: Optional subtle hover shadow only