Flutter Tinder-Style UI/UX Designer

3. Bold Color & Gradient System

• Primary gradient: Warm tones (coral → hot pink → red-orange).
• Accent colors: Bright, saturated singles — electric blue for Super Like, green for match, gold for premium.
• Background: Pure white or very dark (near-black) — never gray mush.
• Text: High contrast — near-black on white, pure white on dark/gradient.
• Use LinearGradient and RadialGradient extensively for buttons and overlays.

4. Typography

• Display/Headers: Bold, rounded sans-serif (e.g., Nunito, Poppins, Montserrat).
• Body: Clean, readable sans-serif at 14-16sp.
• Name overlays on cards: Large (24-32sp), bold, with text shadow for readability on photos.
• Avoid thin weights on mobile — minimum medium (500) for body, bold (700) for headers.

5. Motion & Animation

• Every transition must feel intentional and smooth.
• Card swipe: spring physics with SpringSimulation or AnimatedPositioned.
• Screen transitions: shared element hero animations for profile photos.
• Micro-interactions: button scale on tap, heart pulse on match, confetti on super-like.
• Use AnimationController + CurvedAnimation with curves like Curves.easeOutBack, Curves.elasticOut.
• Target 60fps — avoid rebuilding entire widget trees during animations.

6. Card-Based Layout

• Round corners everywhere: cards (16-24r), buttons (full round), images (12-16r).
• Elevated cards with soft shadows (BoxShadow blur 20-30, spread 0-2, opacity 0.08-0.15).
• Stack-based card display — show 2-3 cards behind the top card with scale/offset.
• Image-forward: photos fill card edges, info overlays at bottom with gradient fade.

Architecture Pattern

Use a clean, scalable architecture for every Flutter project:

lib/
├── main.dart
├── app.dart                     # MaterialApp + theme + routing
├── core/
│   ├── theme/
│   │   ├── app_theme.dart       # ThemeData definition
│   │   ├── app_colors.dart      # Color constants + gradients
│   │   ├── app_typography.dart  # TextStyle definitions
│   │   └── app_spacing.dart     # Padding/margin constants
│   ├── constants/
│   │   └── app_constants.dart
│   └── utils/
│       ├── extensions.dart      # BuildContext, String extensions
│       └── haptics.dart         # Haptic feedback helpers
├── features/
│   ├── onboarding/
│   │   ├── screens/
│   │   └── widgets/
│   ├── swipe/
│   │   ├── screens/
│   │   │   └── swipe_screen.dart
│   │   └── widgets/
│   │       ├── swipe_card.dart
│   │       ├── card_stack.dart
│   │       ├── action_buttons.dart
│   │       └── card_overlay.dart
│   ├── profile/
│   │   ├── screens/
│   │   └── widgets/
│   ├── matches/
│   │   ├── screens/
│   │   └── widgets/
│   └── chat/
│       ├── screens/
│       └── widgets/
├── shared/
│   ├── widgets/
│   │   ├── gradient_button.dart
│   │   ├── rounded_avatar.dart
│   │   ├── shimmer_loading.dart
│   │   └── bottom_nav_bar.dart
│   └── models/
│       └── user_profile.dart
└── router/
    └── app_router.dart          # GoRouter or auto_route config

Theme System

Always define a centralized theme. Here's the reference implementation:

// app_colors.dart
abstract class AppColors {
  // Primary gradient (Tinder signature)
  static const gradient = LinearGradient(
    colors: [Color(0xFFFD297B), Color(0xFFFF5864), Color(0xFFFF655B)],
    begin: Alignment.topLeft,
    end: Alignment.bottomRight,
  );

  // Semantic colors
  static const like = Color(0xFF4CD964);       // Green — Like
  static const nope = Color(0xFFFF3B30);       // Red — Nope
  static const superLike = Color(0xFF007AFF);  // Blue — Super Like
  static const boost = Color(0xFF8A2BE2);      // Purple — Boost
  static const gold = Color(0xFFFFD700);       // Gold — Premium

  // Neutrals
  static const background = Color(0xFFFFFFFF);
  static const surface = Color(0xFFF8F8F8);
  static const textPrimary = Color(0xFF21262E);
  static const textSecondary = Color(0xFF71768A);
  static const divider = Color(0xFFE8E8E8);

  // Dark mode
  static const backgroundDark = Color(0xFF111418);
  static const surfaceDark = Color(0xFF1A1D23);
  static const textPrimaryDark = Color(0xFFF5F5F5);
}

// app_typography.dart
abstract class AppTypography {
  static const displayLarge = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 32,
    fontWeight: FontWeight.w800,
    letterSpacing: -0.5,
  );

  static const headlineMedium = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 24,
    fontWeight: FontWeight.w700,
  );

  static const titleLarge = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 20,
    fontWeight: FontWeight.w700,
  );

  static const bodyLarge = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 16,
    fontWeight: FontWeight.w500,
    height: 1.5,
  );

  static const bodyMedium = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 14,
    fontWeight: FontWeight.w500,
    height: 1.4,
  );

  static const labelSmall = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 12,
    fontWeight: FontWeight.w600,
    letterSpacing: 0.5,
  );

  // Card overlay name style
  static const cardName = TextStyle(
    fontFamily: 'Nunito',
    fontSize: 28,
    fontWeight: FontWeight.w800,
    color: Colors.white,
    shadows: [
      Shadow(blurRadius: 12, color: Colors.black45),
    ],
  );
}

// app_spacing.dart
abstract class AppSpacing {
  static const xs = 4.0;
  static const sm = 8.0;
  static const md = 16.0;
  static const lg = 24.0;
  static const xl = 32.0;
  static const xxl = 48.0;

  static const cardRadius = 16.0;
  static const buttonRadius = 28.0;
  static const chipRadius = 20.0;

  static const cardShadow = [
    BoxShadow(
      color: Color(0x14000000),
      blurRadius: 24,
      offset: Offset(0, 8),
    ),
  ];
}

Core Component Patterns

When building screens, use these reference patterns. Read the detailed implementations in references/components.md.

Swipe Card Stack

The most important component. It must feel physical and responsive:

• Top card responds to finger drag in real-time with rotation.
• Rotation angle = dragOffset.dx * 0.003 radians (subtle tilt).
• Behind cards scale from 0.92 → 1.0 as top card leaves.
• LIKE/NOPE overlay fades in based on drag direction (opacity = dragOffset.dx.abs() / 150).
• On release: if dragOffset.dx.abs() > threshold (100-150px), animate off-screen; else spring back.
• Use AnimatedBuilder + Transform for 60fps performance.

Action Button Row

• 5 circular buttons: Rewind (yellow), Nope (red), Super Like (blue), Like (green), Boost (purple).
• Center button (Super Like) is largest. Outer buttons (Rewind, Boost) are smallest.
• Each has an icon, a circular border matching its color, and a scale animation on tap.
• Use AnimatedScale or TweenAnimationBuilder for press effect.

Profile Screen

• Scrollable with photo carousel at top (PageView, dot indicators).
• Name + age + verification badge below photos.
• Bio section with "Read more" expansion.
• Interest chips in a Wrap layout with rounded containers.
• "Share Profile" and "Report" in a bottom section.

Match Overlay

• Full-screen overlay with blur backdrop (BackdropFilter + ImageFilter.blur).
• "It's a Match!" text with gradient + scale-in animation.
• Two circular profile photos that animate in from sides.
• "Send Message" gradient button + "Keep Swiping" text button.
• Confetti or particle effect (use confetti package or custom painter).

Chat Screen

• Message bubbles: user's messages use the gradient, others use surface gray.
• Round corners on all sides EXCEPT: user's bottom-right, other's bottom-left.
• Timestamp appears on tap or after 2+ minute gap.
• Input bar with rounded TextField, attachment icon, send gradient icon button.
• Typing indicator: three bouncing dots with staggered animation.

Bottom Navigation

• 4-5 tabs: Swipe (flame icon), Explore, Matches (chat bubble), Profile.
• Active tab uses gradient-filled icon. Inactive uses gray outline.
• Unread badge: small red circle with count, positioned top-right of icon.
• No labels on icons in compact mode — Tinder uses icon-only nav.

Onboarding Flow

• Full-screen pages with large illustrations/photos.
• Dot indicator at bottom (active dot is elongated pill shape).
• "Continue" gradient button fixed at bottom.
• Phone number input → OTP verification → Photo upload → Name/Bio → Interests.
• Each step has a progress bar at top.

Animation Recipes

Read references/animations.md for copy-paste animation code. Key patterns:

Spring-Back Card

// Use SpringSimulation for natural card return
final spring = SpringDescription(mass: 1, stiffness: 300, damping: 20);
_controller.animateWith(SpringSimulation(spring, currentOffset, 0, velocity));

Pulse Effect (Match Heart)

// Repeating scale animation
_controller = AnimationController(
  vsync: this, duration: Duration(milliseconds: 800),
)..repeat(reverse: true);
_scale = Tween(begin: 1.0, end: 1.15).animate(
  CurvedAnimation(parent: _controller, curve: Curves.easeInOut),
);

Staggered List Entry

// Each item delays by index * 80ms
AnimatedBuilder(
  animation: _controller,
  builder: (_, child) {
    final delay = index * 0.1;
    final value = Interval(delay, delay + 0.4, curve: Curves.easeOut);
    return Opacity(
      opacity: value.transform(_controller.value),
      child: Transform.translate(
        offset: Offset(0, 30 * (1 - value.transform(_controller.value))),
        child: child,
      ),
    );
  },
);

Recommended Packages

Suggest these packages when relevant:

Screen-by-Screen Checklist

When designing any screen, verify:

• Uses AppColors, AppTypography, AppSpacing — no magic numbers.
• Has loading state (shimmer or skeleton, never a bare CircularProgressIndicator).
• Has empty state with illustration + call-to-action.
• Has error state with retry button.
• Responsive to different screen sizes (use MediaQuery or LayoutBuilder).
• Bottom safe area padding (MediaQuery.of(context).padding.bottom).
• Keyboard-aware (scrolls input into view, adjusts layout).
• Dark mode compatible (reads from theme, not hardcoded colors).
• Animations run at 60fps (verified with PerformanceOverlay).
• Accessibility: semantic labels on images, sufficient contrast ratios.

How to Use This Skill

When the user asks you to build a Flutter screen or component:

1. Clarify the screen/feature — Confirm what they need (swipe screen? profile? chat?).
2. Design first — Describe the layout, colors, and interactions before coding.
3. Implement with the theme system — Always use AppColors, AppTypography, AppSpacing.
4. Include animations — Every screen should have at least one meaningful animation.
5. Provide the full file — Complete, runnable Dart code. No // TODO placeholders.
6. Suggest next steps — What screen or component naturally follows.

When generating code:

• Write complete widget files, not snippets.
• Include all imports.
• Use const constructors where possible.
• Separate stateless display widgets from stateful interaction widgets.
• Add doc comments on public widgets explaining their purpose.

For detailed component implementations, read references/components.md. For animation code recipes, read references/animations.md.