Front UI Skills
Opinionated constraints for building Front-style interfaces with AI agents.
When to Apply
Reference these guidelines when:
- Building light-mode interfaces
- Creating Front-inspired design systems
- Implementing UIs with Inter font and 4px grid
Colors
- SHOULD use light backgrounds for primary surfaces
- MUST use
#FFFFFF as page background (surface-base)
- MUST use
#C8CC51 for primary actions and focus states (accent)
- SHOULD reduce color palette (currently 30 colors detected)
- MUST maintain text contrast ratio of at least 4.5:1 for accessibility
Semantic Tokens
| Token |
HEX |
RGB |
Usage |
surface-base |
#FFFFFF |
rgb(255,255,255) |
Page background |
surface-raised |
#240733 |
rgb(36,7,51) |
Cards, modals, raised surfaces |
surface-overlay |
#503AF3 |
rgb(80,58,243) |
Overlays, tooltips, dropdowns |
text-primary |
#978BF0 |
rgb(151,139,240) |
Headings, body text |
text-secondary |
#D1D1D1 |
rgb(209,209,209) |
Secondary, muted text |
text-tertiary |
#8F8F8F |
rgb(143,143,143) |
Additional text |
border-default |
#DDD4F5 |
rgb(221,212,245) |
Subtle borders, dividers |
accent |
#C8CC51 |
rgb(200,204,81) |
Primary actions, links, focus |
warning |
#B49F65 |
rgb(180,159,101) |
Warning states, cautions |
Typography
- MUST use
Inter as primary font family
- SHOULD use single font family for consistency
- MUST use
58px / 700 for primary headings
- MUST use
26px / 700 for body text
- SHOULD reduce font weights (currently 4 detected)
- MUST use
text-balance for headings and text-pretty for body text
- SHOULD use
tabular-nums for numeric data
- NEVER modify letter-spacing unless explicitly requested
Text Styles
| Style |
Font |
Size |
Weight |
Color |
Count |
heading-1 |
Inter |
58px |
700 |
#E7E1E8 |
1 |
body |
Inter |
26px |
700 |
#EBE5EC |
1 |
text-17px |
Inter |
17px |
400 |
#AC99B3 |
1 |
text-16px |
Inter |
16px |
400 |
#46541B |
1 |
text-15px |
Inter |
15px |
400 |
#977FAF |
1 |
text-15px |
Inter |
15px |
400 |
#594B5F |
1 |
text-15px |
Inter |
15px |
400 |
#BCABC2 |
1 |
text-15px |
Inter |
15px |
400 |
#C8B8CD |
1 |
text-14px |
Inter |
14px |
400 |
#977FB0 |
1 |
text-14px |
Inter |
14px |
400 |
#9880B0 |
1 |
Typography Reference
Font Families:
Font Sizes: 5px, 6px, 7px, 8px, 9px, 10px, 11px, 12px, 13px, 14px, 15px, 16px, 17px, 26px, 58px
Spacing
- MUST use 4px grid for spacing
- SHOULD use spacing from scale: 1px, 2px, 3px, 4px, 5px, 6px, 8px, 14px
- SHOULD use 2px as default gap between elements
- NEVER use arbitrary spacing values (use design scale)
- SHOULD maintain consistent padding within containers
Borders
- MUST use border-radius from scale: 1px, 2px, 3px, 5px, 6px, 18px, 20px
- SHOULD use 20px+ radius for pill-shaped elements
- SHOULD limit border widths to: 1px, 2px, 5px
- SHOULD use 3px as default border-radius
- NEVER use arbitrary border-radius values (use design scale)
- SHOULD use subtle borders (1px) for element separation
Border Radius Reference
Scale: 1px, 2px, 3px, 5px, 6px, 18px, 20px
Layout
- MUST design for 1920px base viewport width
- SHOULD use consistent element widths: 10px, 11px, 6px, 8px, 20px
- SHOULD maintain text-heavy layout with clear hierarchy
- NEVER use
h-screen, use h-dvh for full viewport height
- MUST respect
safe-area-inset for fixed elements
- SHOULD use
size-* for square elements instead of w-* + h-*
Detected Layout Patterns
- Main Content: width: 1920px, height: 639px
- Main Content: width: 1267px, height: 569px
- Main Content: width: 1255px, height: 569px
- Header: height: 75px
Components
Buttons
| Variant |
Background |
Text |
Border |
Height |
Radius |
| Ghost |
transparent |
#978BF0 |
none |
- |
- |
Interactive States
Focus
- MUST use
2px outline with accent color (#C8CC51)
- MUST use
2px outline-offset
- NEVER remove focus indicators
Hover
- Buttons (primary): lighten background by 10%
- Buttons (secondary): use
#240733 background
- List items: use
#240733 background
Disabled
- MUST use
opacity: 0.5
- MUST use
cursor: not-allowed
Interaction
- MUST use an
AlertDialog for destructive or irreversible actions
- SHOULD use structural skeletons for loading states
- MUST show errors next to where the action happens
- NEVER block paste in
input or textarea elements
- MUST add an
aria-label to icon-only buttons
Animation
- NEVER add animation unless it is explicitly requested
- MUST animate only compositor props (
transform, opacity)
- NEVER animate layout properties (
width, height, top, left, margin, padding)
- SHOULD use
ease-out on entrance animations
- NEVER exceed
200ms for interaction feedback
- SHOULD respect
prefers-reduced-motion
Performance
- NEVER animate large
blur() or backdrop-filter surfaces
- NEVER apply
will-change outside an active animation
- NEVER use
useEffect for anything that can be expressed as render logic
1---2name: front-ui-skills3description: Front's UI design system. Use when building interfaces inspired by Front's aesthetic - light mode, Inter font, 4px grid.4license: MIT5---6
7# Front UI Skills
8
9Opinionated constraints for building Front-style interfaces with AI agents.
10
11## When to Apply
12
13Reference these guidelines when:
14- Building light-mode interfaces
15- Creating Front-inspired design systems
16- Implementing UIs with Inter font and 4px grid
17
18## Colors
19
20- SHOULD use light backgrounds for primary surfaces
21- MUST use `#FFFFFF` as page background (`surface-base`)
22- MUST use `#C8CC51` for primary actions and focus states (`accent`)
23- SHOULD reduce color palette (currently 30 colors detected)
24- MUST maintain text contrast ratio of at least 4.5:1 for accessibility
25
26### Semantic Tokens
27
28| Token | HEX | RGB | Usage |
29|-------|-----|-----|-------|
30| `surface-base` | #FFFFFF | rgb(255,255,255) | Page background |
31| `surface-raised` | #240733 | rgb(36,7,51) | Cards, modals, raised surfaces |
32| `surface-overlay` | #503AF3 | rgb(80,58,243) | Overlays, tooltips, dropdowns |
33| `text-primary` | #978BF0 | rgb(151,139,240) | Headings, body text |
34| `text-secondary` | #D1D1D1 | rgb(209,209,209) | Secondary, muted text |
35| `text-tertiary` | #8F8F8F | rgb(143,143,143) | Additional text |
36| `border-default` | #DDD4F5 | rgb(221,212,245) | Subtle borders, dividers |
37| `accent` | #C8CC51 | rgb(200,204,81) | Primary actions, links, focus |
38| `warning` | #B49F65 | rgb(180,159,101) | Warning states, cautions |
39
40## Typography
41
42- MUST use `Inter` as primary font family
43- SHOULD use single font family for consistency
44- MUST use `58px` / `700` for primary headings
45- MUST use `26px` / `700` for body text
46- SHOULD reduce font weights (currently 4 detected)
47- MUST use `text-balance` for headings and `text-pretty` for body text
48- SHOULD use `tabular-nums` for numeric data
49- NEVER modify letter-spacing unless explicitly requested
50
51### Text Styles
52
53| Style | Font | Size | Weight | Color | Count |
54|-------|------|------|--------|-------|-------|
55| `heading-1` | Inter | 58px | 700 | #E7E1E8 | 1 |
56| `body` | Inter | 26px | 700 | #EBE5EC | 1 |
57| `text-17px` | Inter | 17px | 400 | #AC99B3 | 1 |
58| `text-16px` | Inter | 16px | 400 | #46541B | 1 |
59| `text-15px` | Inter | 15px | 400 | #977FAF | 1 |
60| `text-15px` | Inter | 15px | 400 | #594B5F | 1 |
61| `text-15px` | Inter | 15px | 400 | #BCABC2 | 1 |
62| `text-15px` | Inter | 15px | 400 | #C8B8CD | 1 |
63| `text-14px` | Inter | 14px | 400 | #977FB0 | 1 |
64| `text-14px` | Inter | 14px | 400 | #9880B0 | 1 |
65
66### Typography Reference
67
68**Font Families:**
69- `Inter` (used 79x)
70
71**Font Sizes:** 5px, 6px, 7px, 8px, 9px, 10px, 11px, 12px, 13px, 14px, 15px, 16px, 17px, 26px, 58px
72
73## Spacing
74
75- MUST use 4px grid for spacing
76- SHOULD use spacing from scale: 1px, 2px, 3px, 4px, 5px, 6px, 8px, 14px
77- SHOULD use 2px as default gap between elements
78- NEVER use arbitrary spacing values (use design scale)
79- SHOULD maintain consistent padding within containers
80
81## Borders
82
83- MUST use border-radius from scale: 1px, 2px, 3px, 5px, 6px, 18px, 20px
84- SHOULD use 20px+ radius for pill-shaped elements
85- SHOULD limit border widths to: 1px, 2px, 5px
86- SHOULD use 3px as default border-radius
87- NEVER use arbitrary border-radius values (use design scale)
88- SHOULD use subtle borders (1px) for element separation
89
90### Border Radius Reference
91
92**Scale:** 1px, 2px, 3px, 5px, 6px, 18px, 20px
93
94## Layout
95
96- MUST design for 1920px base viewport width
97- SHOULD use consistent element widths: 10px, 11px, 6px, 8px, 20px
98- SHOULD maintain text-heavy layout with clear hierarchy
99- NEVER use `h-screen`, use `h-dvh` for full viewport height
100- MUST respect `safe-area-inset` for fixed elements
101- SHOULD use `size-*` for square elements instead of `w-*` + `h-*`
102
103### Detected Layout Patterns
104
105- **Main Content**: width: 1920px, height: 639px
106- **Main Content**: width: 1267px, height: 569px
107- **Main Content**: width: 1255px, height: 569px
108- **Header**: height: 75px
109
110## Components
111
112### Buttons
113
114| Variant | Background | Text | Border | Height | Radius |
115|---------|------------|------|--------|--------|--------|
116| Ghost | transparent | #978BF0 | none | - | - |
117
118## Interactive States
119
120### Focus
121
122- MUST use `2px` outline with accent color (`#C8CC51`)
123- MUST use `2px` outline-offset
124- NEVER remove focus indicators
125
126### Hover
127
128- Buttons (primary): lighten background by 10%
129- Buttons (secondary): use `#240733` background
130- List items: use `#240733` background
131
132### Disabled
133
134- MUST use `opacity: 0.5`
135- MUST use `cursor: not-allowed`
136
137## Interaction
138
139- MUST use an `AlertDialog` for destructive or irreversible actions
140- SHOULD use structural skeletons for loading states
141- MUST show errors next to where the action happens
142- NEVER block paste in `input` or `textarea` elements
143- MUST add an `aria-label` to icon-only buttons
144
145## Animation
146
147- NEVER add animation unless it is explicitly requested
148- MUST animate only compositor props (`transform`, `opacity`)
149- NEVER animate layout properties (`width`, `height`, `top`, `left`, `margin`, `padding`)
150- SHOULD use `ease-out` on entrance animations
151- NEVER exceed `200ms` for interaction feedback
152- SHOULD respect `prefers-reduced-motion`
153
154## Performance
155
156- NEVER animate large `blur()` or `backdrop-filter` surfaces
157- NEVER apply `will-change` outside an active animation
158- NEVER use `useEffect` for anything that can be expressed as render logic