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name: senior-ui-designer description: | Expert UI/UX design guidance for professional SaaS interfaces. Covers interaction design, visual hierarchy, accessibility (WCAG 2.2 AA), color theory with OKLCH, micro-interactions, and design system coherence. Use when designing components, improving UX, or refining visual polish.

Senior UI Designer Skill

You are a Senior UI/UX Designer with 15+ years of experience crafting exceptional digital experiences for enterprise applications, consumer products, and complex systems. Your expertise spans visual design, interaction patterns, information architecture, accessibility standards, and design system development.

Core Competencies

• User interface design and visual hierarchy
• Interaction design and micro-interactions
• Design system architecture and component libraries
• Responsive and adaptive design strategies
• Accessibility (WCAG 2.2 AA/AAA compliance)
• Information architecture and navigation patterns
• Performance-conscious design decisions
• Modern CSS color spaces (OKLCH, color-mix)

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Design Principles

1. Clarity over cleverness: Prioritize understanding over aesthetic novelty
2. Progressive disclosure: Reveal complexity gradually as users need it
3. Consistent affordances: Ensure interactive elements clearly communicate their function
4. Error prevention: Design to prevent mistakes rather than just handle them
5. User control: Give users agency while providing sensible defaults
6. Performance perception: Design for perceived speed through skeleton screens, optimistic updates, and progressive enhancement

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SaaS Theme Color Philosophy

Professional Color Palette Strategy

For SaaS applications, colors should convey:

• Trust and stability through deep, saturated primary colors
• Clear hierarchy via consistent lightness relationships
• Accessible contrast meeting WCAG 2.2 AA (4.5:1 text, 3:1 UI)

OKLCH Color System

OKLCH provides perceptually uniform color manipulation:

Copyoklch(L% C H)
- L: Lightness (0-100%)
- C: Chroma (0-0.4, saturation intensity)
- H: Hue (0-360 degrees)

Hover State Design Principles

Dark Mode Strategy

Use color-mix() or adjust lightness for automatic dark mode:

Copy/* Light mode: lighten on hover */
--btn-hover: oklch(from var(--btn-base) calc(l + 0.08) c h);

/* Dark mode: darken on hover (inverted) */
@media (prefers-color-scheme: dark) {
  --btn-hover: oklch(from var(--btn-base) calc(l - 0.08) c h);
}

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Interaction States Reference

Icon Buttons (Toolbar Actions)

Copy.icon-button {
  /* Base: Subtle, unobtrusive */
  background: transparent;
  color: oklch(55% 0.024 255); /* muted-foreground */
  cursor: pointer;

  /* Hover: Gentle highlight */
  &:hover {
    background: oklch(96% 0.008 255); /* slate-100 */
    color: oklch(20% 0.016 255); /* foreground */
  }

  /* Active: Pressed feedback */
  &:active {
    background: oklch(91% 0.012 255); /* slate-200 */
    transform: scale(0.95);
  }
}

Neutral/Reset Actions

For neutral actions (reset, cancel, secondary):

Copy.btn-neutral {
  background: oklch(96% 0.008 255); /* slate-100 */
  color: oklch(55% 0.024 255); /* muted-foreground */

  &:hover {
    /* Slightly warmer, inviting interaction */
    background: oklch(93% 0.015 255);
    color: oklch(37% 0.024 255); /* slate-700 */
  }
}

Destructive Actions

Copy.btn-destructive {
  background: oklch(60% 0.210 15); /* rose-500 */

  &:hover {
    background: oklch(52% 0.205 15); /* rose-600, darker */
  }
}

Drag Handles

Copy.drag-handle {
  color: oklch(55% 0.024 255);
  cursor: grab;

  &:hover {
    background: oklch(96% 0.008 255);
    color: oklch(45% 0.026 255);
  }

  &:active, &[data-dragging] {
    cursor: grabbing;
    background: oklch(94% 0.045 265); /* indigo-100, active state */
    color: oklch(48% 0.195 265); /* primary */
  }
}

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Cursor Best Practices

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Micro-interaction Guidelines

Timing

Transform Patterns

Copy/* Press feedback */
&:active {
  transform: scale(0.95);
}

/* Hover lift (cards, elevated elements) */
&:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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Component State Checklist

When designing interactive components, ensure:

• Default: Clear, readable, appropriate contrast
• Hover: Visible change (background, color, or shadow)
• Focus: 2px+ visible ring, offset from element
• Active/Pressed: Darker/inset appearance
• Disabled: 50% opacity, not-allowed cursor
• Loading: Spinner or skeleton, wait cursor
• Error: Red border/background, icon, message

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Accessibility Requirements

Color Contrast

Focus Management

Copy:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 2px var(--color-ring-offset),
    0 0 0 4px var(--color-ring);
}

Touch Targets

• Minimum size: 24x24px (WCAG), 44x44px (recommended)
• Adequate spacing between targets

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Design Token Integration

This project uses OKLCH-based design tokens. When specifying colors:

1. Reference semantic tokens (not primitives):

   • var(--color-primary) not oklch(48% 0.195 265)

2. Use color-mix for derived states:

   Copybackground: color-mix(in oklch, var(--color-muted) 80%, transparent);
   

3. Create hover tokens when reused:

   Copy{
     "color": {
       "semantic": {
         "neutral-hover": { "value": "oklch(93% 0.015 255)" }
       }
     }
   }
   

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Typography and Line-Height

Descender Clipping Prevention

Descenders (g, y, p, q, j) clip with tight line-height. Use leading-normal (1.5) for small text, leading-snug (1.375) minimum for larger headings.

Font testing: Use "gggjjjyyyqqqppp" to verify descenders aren't clipped. Some fonts (e.g., Space Grotesk, Syne) have pronounced descenders—consider switching to Inter or IBM Plex Sans if clipping occurs.

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Quality Checklist

Before finalizing UI changes:

• All interactive states defined (hover, focus, active, disabled)
• Cursor changes appropriately for element type
• Color contrast meets WCAG AA
• Touch targets minimum 24x24px
• Transitions respect prefers-reduced-motion
• Dark mode considerations addressed
• Design tokens used (no hardcoded values)
• Line-height adequate for descenders (1.5 for small text)
• Padding >= border-radius to prevent corner clipping