Responsive & Adaptive Timing

Responsive timing adapts duration to context: device capability, travel distance, user preferences, and interaction type. One duration doesn't fit all situations.

Disney Principles for Adaptive Motion

Context-Aware Application

Squash & Stretch: Scale with device - more subtle on mobile (less screen real estate for deformation).

Anticipation: Shorter on touch devices - touch users expect faster response than mouse users.

Staging: Adapt to viewport - smaller screens need more focused staging, less simultaneous motion.

Straight Ahead/Pose to Pose: Same approach, scaled duration - poses stay, timing adjusts.

Follow Through: Proportional to distance - longer travel = more follow-through time.

Slow In/Slow Out: Adjust curve intensity - faster animations need sharper easing.

Arcs: Same paths, different speeds - arc shape remains, traversal time changes.

Secondary Action: Reduce on mobile - fewer simultaneous animations for performance.

Timing: THE adaptive variable - timing changes, principles stay.

Exaggeration: Less on smaller screens - proportional to viewport/element size.

Solid Drawing: Performance-aware - reduce 3D transforms on weaker devices.

Appeal: Context-appropriate - what feels right on desktop may feel slow on mobile.

Adaptive Strategies

Distance-Based Duration

/* Base duration for reference distance */
--base-duration: 300ms;
--base-distance: 100px;

/* Duration scales with distance */
/* 50px travel = 200ms, 200px travel = 450ms */

function getDuration(distance) {
  const baseDuration = 300;
  const baseDistance = 100;
  return Math.min(600, baseDuration * Math.sqrt(distance / baseDistance));
}

Device-Based Duration

/* Desktop - full duration */
.transition { transition-duration: 400ms; }

/* Tablet - slightly faster */
@media (max-width: 1024px) {
  .transition { transition-duration: 350ms; }
}

/* Mobile - faster for perceived responsiveness */
@media (max-width: 768px) {
  .transition { transition-duration: 250ms; }
}

Preference-Based Duration

/* Respect reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  .transition {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}

/* Reduce motion, don't eliminate */
@media (prefers-reduced-motion: reduce) {
  .transition {
    transition-duration: 100ms;
    transform: none; /* Only opacity fades */
  }
}

Context Rules

Context	Duration Adjustment
Touch device	-25% from desktop
Small viewport	-20% from desktop
Large travel distance	+50% base
Small travel distance	-30% base
User prefers reduced	Instant or minimal
Low power mode	-50% or disabled
High-frequency action	Use minimum duration
First-time view	Full duration
Repeat interaction	Reduced duration

Implementation Pattern

:root {
  --duration-instant: 50ms;
  --duration-fast: 150ms;
  --duration-normal: 300ms;
  --duration-slow: 500ms;
}

@media (max-width: 768px) {
  :root {
    --duration-fast: 100ms;
    --duration-normal: 200ms;
    --duration-slow: 350ms;
  }
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --duration-instant: 0ms;
    --duration-fast: 0ms;
    --duration-normal: 100ms;
    --duration-slow: 150ms;
  }
}

Key Insight

Great animation adapts like typography adapts - what works at one size/context may not work at another. Build systems, not fixed values. Test across contexts. Duration is a variable, not a constant.

/responsive-adaptive

SKILL.md