# Shaynee Flutter — Design System (Duolingo-study edition)

## 1. How Duolingo Screens Actually Work (first 20 screens)

### Master Layout Template (used on ~80% of screens)

```
┌─────────────────────────────────┐  safe area top
│ [←/×]  ████████░░░░░░  [skip]  │  nav row: 48px tall, 16px padding
├─────────────────────────────────┤
│                                 │
│      [ILLUSTRATION / MASCOT]    │  top zone: ~40% of remaining height
│         centered, ~220px        │  image sits here, NO text
│                                 │
├─────────────────────────────────┤
│                                 │
│  Headline                       │  24px h-padding
│  (bold, 22-26px, dark)          │
│                                 │
│  Sub text (15px, gray)          │
│                                 │
│  ┌─────────────────────────┐   │  option cards: 16px h-padding
│  │ [icon] Label  [radio○]  │   │  card height: 62px
│  └─────────────────────────┘   │  gap between cards: 8px
│  ┌─────────────────────────┐   │
│  │ [icon] Label  [radio○]  │   │
│  └─────────────────────────┘   │
│  ┌─────────────────────────┐   │
│  │ [icon] Label  [radio○]  │   │
│  └─────────────────────────┘   │
│                                 │
├─────────────────────────────────┤
│  ┌─────────────────────────┐   │  button zone: 16px h-padding
│  │        CONTINUE         │   │  button: 52px tall
│  └─────────────────────────┘   │
└─────────────────────────────────┘  safe area bottom
```

### Nav Row breakdown
- Left: back arrow `←` in 36×36 box with gray border OR `×` to exit
- Center: thin progress bar (4px height, full remaining width)
- Right: "Skip" as plain gray text link (no box, no border)
- Background: white, no shadow

### Illustration Zone rules
- NO text inside illustration zone
- Image centered horizontally
- ~40% of screen height (not fixed pixel — scales)
- Mascot/character always faces slightly right or center
- White background behind image (no colored backdrop)

### Card style (EXACT)
```
height:          62px
borderRadius:    12px
background:      white (default) / #f7f7f7 tint (hover)
border:          1.5px solid #e5e5e5 (default)
                 2px solid #58CC02 (Duolingo green, selected)
                 →  for Shaynee: 2px solid #5B4FCF
icon box:        40×40, radius 10, bg #f7f7f7, icon 22px
label:           left-aligned, bold 16px, dark #3c3c3c
radio circle:    right side, 22px, empty or filled+check
gap between:     8px
h-padding:       16px from screen edge
```

### Pressable Button (THE KEY THING — not box-shadow, uses border-bottom trick)
```
height:          52px
borderRadius:    16px
background:      #58CC02 (Duo green)  →  Shaynee: #5B4FCF
border-bottom:   4px solid #58A700   →  Shaynee: 4px solid #3D32A8
                 (this IS the shadow — not box-shadow, not gradient)
text:            WHITE, ExtraBold, 15px, uppercase or title-case
disabled state:  bg #e5e5e5, border-bottom #b0b0b0, text gray
pressed state:   translateY(+4px), border-bottom: 0 (collapses — button "sinks")
width:           full (16px h-padding each side)
```

### Specific screen patterns

**Screen 1 — Splash/Welcome**
```
BG: white (NOT gradient)
Center: Duo mascot (large, ~280px, animated float)
Below mascot:
  "Learn a language\nfor free." (bold 28px, centered)
Bottom stack:
  [GET STARTED] green pressable button
  [I already have an account] — plain text link, no button style
```

**Screen 2 — Reason/Goal (first question)**
```
Nav: [×]  ░░░░░░░░░░  [no skip]
Illustration: topic-specific art (school bag, brain, etc), centered
Headline: "What is your reason for learning?" (22px bold)
Cards: list of 5-7 options (career, family, travel, school, brain, other)
Bottom: [CONTINUE] — disabled until selection
```

**Screen 3 — Language selection**
```
Nav row with progress
Grid of flag+name cards (2 columns or scrollable list)
Searchable (search bar at top of list area)
Bottom: [CONTINUE]
```

**Screen 4-5 — Proficiency / experience**
```
Illustration centered
Big question text
3-4 cards: "I'm new" / "I know a little" / "I'm comfortable" / "It's complicated"
[CONTINUE]
```

**Screen 6-7 — Daily goal**
```
Illustration: Duo with calendar or clock
Question: "Choose your daily goal"
Cards: Casual (5min) / Regular (10min) / Serious (15min) / Intense (20min)
Each card has icon + name + description (3 lines in card)
Selected card: green border + light green bg
[CONTINUE]
```

**Screen 8-10 — First mini lesson (before signup)**
```
Quiz layout:
  Top: progress bar (green fill) + × + hearts ♥♥♥
  Middle: question illustration
  Question text below illustration
  Answer options (A/B/C/D) as square/rounded cards in 2×2 grid or vertical
  Bottom: [CHECK] button (green, disabled until pick)
After correct: [CHECK] becomes green checkmark animation, then [CONTINUE]
After wrong: button turns red, explanation text appears below
```

**Screen 11 — Lesson complete / celebration**
```
Confetti animation full screen
Mascot celebrating (arms up)
"You did it!" bold centered
XP earned badge
[CONTINUE]
```

**Screen 12 — Streak intro**
```
Flame icon (large, centered)
"You're on a streak!" 
Explanation of how streaks work
[CONTINUE]
```

**Screen 13-16 — Signup gate**
```
Illustration: Duo with "Save your progress"
"Create a profile to save your progress"
[CREATE PROFILE] green button
[Maybe later] plain text link (NOT a button)
```

**Screen 17-20 — Account creation**
```
Individual input screens, one field per screen:
  Enter your age → Enter your name → Enter email → Set password
Each screen: input field centered, big, full-width below headline
[CONTINUE] stays disabled until field valid
```

---

## 2. Shaynee Design Rules (derived from Duolingo study)

### RULE 1: NO gradients anywhere (kills premium feel on cheap gradient)
### RULE 2: White backgrounds on all content screens
### RULE 3: Pressable button = border-bottom trick, NOT box-shadow
### RULE 4: One illustration zone (top 40%) + one content zone (bottom 60%)
### RULE 5: Button always stuck to bottom, full width, 16px h-padding
### RULE 6: Cards: 62px, border-based selection, no shadows
### RULE 7: Mascot only on: splash, analysing complete, result reveal
### RULE 8: "Skip" / "Maybe later" = plain text, never in a button/box

---

## 3. Shaynee Color System (no gradients)

```dart
// Backgrounds
bgPage:        #FAFAFE  // very light lavender-white
bgSurface:     #FFFFFF  // pure white (cards, inputs)

// Primary (Indigo — replaces Duo's green)
primary:       #5B4FCF
primaryDark:   #3D32A8  // button bottom border
primaryLight:  #EAE7FB  // selected card bg tint
primaryBorder: #5B4FCF  // selected card border

// Text
textHead:      #1C1A2E  // nearly black
textBody:      #4B4B6B  // medium dark
textSub:       #9898AA  // gray subtext
textDisabled:  #C4C4D4

// Borders
borderLight:   #E8E6F0  // card default border
borderMedium:  #D0CDEA  // input default

// Accent
accent:        #FF7EB3  // pink — celebrations, badges only
accentLight:   #FFF0F6

// States
success:       #4CAF50
error:         #FF4B4B
```

---

## 4. Typography — Nunito (Google Fonts)

```dart
// Weights to use:
// 900 Black    → main headlines (36px+)
// 800 ExtraBold → section heads (22-28px), button text
// 700 Bold     → card labels (16px), input text
// 600 SemiBold → body (15px), subtitles
// 500 Medium   → captions (12-13px), subtext
// 400 Regular  → (avoid — too thin)

// Scale:
headline1:  Nunito 900,  36px, lh 1.15
headline2:  Nunito 800,  26px, lh 1.2
title:      Nunito 800,  22px, lh 1.25
subtitle:   Nunito 600,  15px, lh 1.5
body:       Nunito 600,  15px, lh 1.5
caption:    Nunito 500,  12px, lh 1.4
button:     Nunito 800,  15px, lh 1.0, letterSpacing 0.3
```

---

## 5. Component Specs (Flutter implementation)

### SButton (Pressable)
```dart
// Use GestureDetector with onTapDown/onTapUp for press animation
// AnimatedContainer: on press, translate Y +4, remove bottom border

decoration: BoxDecoration(
  color: SColors.primary,           // flat, NO gradient
  borderRadius: BorderRadius.circular(16),
  border: Border(
    bottom: BorderSide(
      color: SColors.primaryDark,   // #3D32A8
      width: 4,                     // THIS is the "shadow"
    ),
  ),
),
// On press: transform translate(0, 4), border bottom 0
// Duration: 80ms
```

### SCard (Option row)
```dart
height: 62,
decoration: BoxDecoration(
  color: selected ? SColors.primaryLight : SColors.bgSurface,
  borderRadius: BorderRadius.circular(12),
  border: Border.all(
    color: selected ? SColors.primary : SColors.borderLight,
    width: selected ? 2.0 : 1.5,
  ),
),
// NO shadow
// Icon box: 40×40, radius 10, bg #f4f2ff (selected) or #f7f7f7
// Radio: right side, 22×22 circle
```

### SProgressBar
```dart
height: 4,
borderRadius: BorderRadius.circular(2),
// Track: SColors.borderLight
// Fill: SColors.primary
// Animate width change: 300ms ease-out
```

---

## 6. Screen Flow & Rules per Screen

| Screen | BG | Illustration zone | Nav | Button text |
|--------|----|--------------------|-----|-------------|
| Splash | White | Shaynee hero (center, large) | none | auto-advance |
| Intro/Welcome | White | Feature art or stats visual | none | "Get started" |
| Name | White | Small Shaynee avatar (top, 100px) | ← + 1/5 + skip | "Continue" |
| Skin type | White | Skin illustration (120px) | ← + 2/5 | "Continue" |
| Age | White | Age illustration (120px) | ← + 3/5 | "Continue" |
| Concerns | White | Skincare illustration (120px) | ← + 4/5 | "Continue" |
| Goal | White | Goal illustration (120px) | ← + 5/5 | "See my results" |
| Analysing | White + spinner | Shaynee pulsing (center) | none | auto-advance |
| Result | White | Shaynee hero mascot (top 35%) | none | "Start my routine" |
| Sign up | White | none | × | "Save my results" |