Depth / Shadows
Depth in a design system refers to the use of layering and shadows (or similar effects) to create a sense of hierarchy and spatial relationships within the interface. It helps users understand which elements are on top, interactive, or more prominent. By defining consistent rules for shadows, z-index layers, and overlapping elements, you establish visual clarity and a cohesive user experience.
Best practices
Define a Limited Elevation Scale
Restrict depth to a few distinct levels (e.g., none, small, medium, large) to keep the interface unified.
Avoid arbitrary shadow or z-index values in individual components.
Maintain Consistency
Use the same shadow tokens for components with similar importance or layer hierarchy (e.g., all dropdown menus share a specific shadow token).
Document specific usage for each token to prevent inconsistency.
Optimize Performance
Excessive or complex shadows can impact rendering performance, especially on mobile devices.
Keep shadows subtle and test across various browsers and platforms.
Consider Accessibility
Shadows should be noticeable enough to provide a visual cue, but not so strong that they conflict with text contrast or create distractions.
For users who rely on high-contrast settings, ensure depth cues work well alongside color accessibility guidelines.
Blend Depth with Other Foundations
Evaluate how shadows interact with colors, radius, and spacing.
For instance, a large corner radius with a strong shadow may look mismatched if not balanced properly.
Document & Evolve
Keep a reference of all depth tokens, including z-index levels and shadow values.
Gather feedback and adjust the system as your product or brand evolves.
Keep the overall depth system minimal—too many layered effects can create visual noise and slow performance.
Summary
Depth brings an added layer (pun intended) of clarity and polish to a design system. By defining standard shadows, z-index hierarchies, and elevation states, you can communicate visual relationships and interactive cues in a consistent manner. A well-managed depth foundation helps users navigate your interface intuitively, reinforcing your brand’s aesthetic and ensuring a cohesive, refined experience.
