LetzAI Design System

Internal reference for the LetzAI product shell — typography, materials, and components that match canvas chrome.

Design system v1.7 · June 2026

Preview theme

Principles

LetzAI uses an Apple-like neutral palette. Hierarchy comes from opacity and weight, not color accents in the app shell.

Accent = ink. --accentcolor resolves to --color. No product purple in app chrome.
Marketing exception. Landing pages (.lp2) may use --marketing-accent, scoped to marketing CSS only.
Canvas exception. User strokes and picks can be any color; default focus/selection chrome uses ink.
Marketing heroes use --text-display-hero (landing .lp2-hero h1).
Canvas typography. In-product headings use the compact canvas scale (--text-page-title through --text-panel-label), not global h1–h6.
Materials. Frosted chrome uses blur + translucent surfaces — not tinted glass.
Design artifacts. Sandboxed iframe designs use public/design-starters/*/tokens.css — separate from the app shell.

Control decision tree

App-wide actions.stdbutton / .altbutton in app-buttons.css

Canvas chrome.cv-* in canvas.css — toolbars, inspector, pills

DropdownsAppListSelect / .app-dropdown — not native <select>

Legacystyles.css patterns — migrate, do not extend

Color

Semantic tokens for the active preview theme. Semantic greens/reds are for feedback only — not decorative chrome.

Text hierarchy

--colorInk / primary text

--text-secondarySecondary text

--text-tertiaryTertiary text

Surfaces

--bgPage background

--verylightbgSubtle surface

--popupbgPopup / panel

--headerbgHeader

--surface-chromeFrosted chrome

--scrim-defaultModal scrim

--scrim-denseDense scrim (no blur)

--modalbgModal tint

--skeleton-baseSkeleton base

Interactive / chrome

--hairlineHairline border

--bordercolorBorder

--buttonbgButton fill

--lighthoverHover fill

--stdbuttonbgPrimary fill (= ink)

--stdbuttoncolorPrimary fill text

--accentcolorAccent (= ink)

--focus-ringFocus ring

--control-font-sizeCanvas control text

--control-height-mdCanvas control height

Semantic (feedback only)

--color-successSuccess

--color-errorError

--color-warningWarning

Typography

Marketing display for logged-out landing heroes; canvas scale for in-product UI. Titles use --font-title (Space Grotesk Semibold); body and UI copy stay on --font-sans (Inter).

Inter 400 body · 500 UI · Space Grotesk 600 titles

Logged-out landing scale — larger than in-app canvas titles. Space Grotesk Semibold, tight tracking.

Create anything.

Generate, edit, and organize on an infinite canvas.

Create anything.

Marketing heroheading-display-hero--text-display-hero.lp2-hero h1 · .heading-display-hero

Built for creative teams

Marketing sectionheading-display-section--text-display-section.lp2-section-title · .heading-display-section

In-app canvas scale

Seven steps from 2rem page titles down to 11px panel labels. Pick by structural depth: page list → settings section → top bar name → inspector group → uppercase row label — not by how “important” the copy feels.

Largest to smallest above. Page title is a step above everything else; chrome and chat sit between section copy and inspector labels. Panel labels are 11px, uppercase, secondary ink.

Sample	Rendered	Class	Token	Where
My Boards	2.2rem`2.2rem`	`cv-heading-page`	`--text-page-title`	.cv-list-title · .app-page-title
Board settings	20px`20px`	`app-section-title`	`--text-section-title`	Settings / modal sections
Sharing & access	15px`15px`	`app-subsection-title`	`--text-subsection-title`	Nested settings blocks
Untitled board	14px`14px`	`cv-heading-chrome`	`--text-chrome-title`	.cv-topbar-title
Next steps	13px`13px`	`cv-heading-chat`	`--text-chat-heading`	.cv-cc-md h1–h6
Layout	13px`13px`	`cv-heading-section`	`--text-panel-title`	.cv-inspector-section-title
Layers	12px`12px`	`cv-heading-panel-label`	`--text-panel-label`	.cv-layers-heading-row · uppercase

Spacing

4px base grid. Prefer tokens over raw pixel values.

--space-14px

--space-28px

--space-312px

--space-416px

--space-520px

--space-624px

--space-832px

--space-1040px

--space-1248px

--space-1664px

Border radius

Radius is contextual: --radius-md for inspector fields, --radius-lg for top-bar controls, --radius-full for toolbars and selection pills.

--radius-nonenone

--radius-smsm (4px)

--radius-mdmd (6px)

--radius-lglg (8px)

--radius-xlxl (12px)

--radius-2xl2xl (16px)

--radius-fullfull

Shadows

--shadow-sm

--shadow-md

--shadow-lg

--shadow-xl

Materials & blur

Frosted chrome, modal scrims, and floating bars use tokenized blur values. Always pair -webkit-backdrop-filter with backdrop-filter for Safari.

Frosted chrome bar

Board title

Developer spec

.app-glass-chrome · --surface-chrome · --blur-md

Modal scrim

Developer spec

.app-backdrop-scrim · --scrim-default · --blur-sm

Floating glass bar

Unsaved changes

Developer spec

.app-glass-float · --blur-xl

When to skip blur

Heavy dialogs that re-render on every interaction should use a denser opaque scrim instead of full-screen blur (see canvas .cv-create-overlay).

Developer spec

.app-backdrop-scrim--dense · backdrop-filter: none

Motion

Hover the box — uses --duration-normal and --ease-default.

Buttons

Use .stdbutton for primary actions and .altbutton for secondary — compact density, one filled button per row.

Primary + secondary

Developer spec

.stdbutton · .altbutton

Sizes

Developer spec

.stdbuttonsmall · .stdbuttonbig

Disabled

Developer spec

.stdbutton[disabled] · .stdbuttondisabled · .altbuttondisabled

Action row

Developer spec

one primary per row

Model badges

Developer spec

.model-badge--letzai

Canvas-specific chrome

Toolbar, inspector, and drawer controls use .cv-* classes where layout-specific.

Icon ghost

Developer spec

.cv-icon-btn

Share actions

Developer spec

.cv-share-btn · .cv-share-primary

Aspect pills

Developer spec

.cv-section-aspect-pill

Primary CTA

Developer spec

.cv-section-generate-btn

Floating toolbar

Developer spec

.cv-toolbar · .cv-tool

Full canvas chrome catalog lives in styles/components/canvas.css.

Form controls

Text inputs use .app-input / .stdtextarea. Dropdowns use AppListSelect — not native <select>.

List select

Developer spec

AppListSelect · .app-dropdown

Property field

Width

Developer spec

.cv-prop-field

Deprecated legacy

Deprecated patterns — do not use in new UI. Prefer .app-input and AppListSelect.

Textarea

Developer spec

.stdtextarea

Text input

Developer spec

.app-input

Search & selection

Search fields, custom list selects, segmented controls, and toggle switches.

Search field

Developer spec

.app-search-input

List select

Native <select> menus are OS-rendered. Use AppListSelect for on-brand dropdown panels.

Closed

Open

Developer spec

AppListSelect · .app-dropdown (not native <select>)

Segmented control

Developer spec

.app-segmented

Toggle switch

Off

Developer spec

.switch · .slider

Feedback & status

Alerts, status chips, and mentions from app-feedback.css.

Alert banners

Board published successfully.

Generation queue is busy — expect a short delay.

Upload failed. Check file size and try again.

Invite collaborators from the Share panel.

Developer spec

.app-alert

Status chips

PublishedPendingFailedDraft

Developer spec

.app-chip

Mention

Use @landscape-lora or @model in prompts.

Developer spec

.app-mention

Loading & empty

Skeleton loaders and empty states from app-layout.css.

Skeleton

Developer spec

.app-skeleton · --skeleton-base

Empty state

No boards yet

Create a board to start generating and organizing assets.

Developer spec

AppEmptyState · .app-empty-state

Modals & overlays

Modal content on --popupbg with scrim from .app-backdrop-scrim.

Modal shell

Developer spec

.app-modal-shell · --popupbg

App screen

Composed hierarchy — how chrome, headings, and actions fit together on one screen.

Summer campaign

Generate assets

One primary action per row. Secondary actions stay ghost or bordered.

Aspect ratio

Body text

Paragraphs, captions, lists, links, and inline code across the app shell.

Primary body

LetzAI helps teams generate, edit, and organize creative assets on an infinite canvas. Default paragraph style at comfortable reading size.

Developer spec

p · --color · --text-base

Secondary

Supporting copy, metadata, and helper text use secondary ink via opacity.

Developer spec

--text-secondary

Tertiary

Timestamps, placeholders, and de-emphasized labels.

Developer spec

--text-tertiary

Disabled

Unavailable or inactive field hints.

Developer spec

--disabledcolor

Caption

Caption text — notifications, footnotes, table meta.

Developer spec

--text-xs

Links

Read the API documentation or use a ghost link button.

Developer spec

.textlink · .ghost-link-btn

Inline code

Set data-theme="dark" on <html> to switch themes.

Developer spec

code

Lists

Generate images from natural-language prompts
Edit and upscale existing assets
Organize work on shared boards

Blockquote

Hierarchy comes from opacity and weight, not product color accents in the app shell.

Developer spec

--text-secondary

Layout & dividers

Hairline dividers, cards, and popup surfaces.

Horizontal divider

Content above

Content below

Developer spec

.app-divider · --hairline

Vertical divider

Developer spec

.app-divider-vertical

Content card

Summer campaign

Updated 2 hours ago · 12 assets

Developer spec

.app-card

Popup surface

Dropdown or panel on popup surface.

Developer spec

--popupbg · --shadow-md

Focus & accessibility

Keyboard focus uses --focus-ring — never hardcoded outline colors.

Focus ring

Tab to the control — uses box-shadow: var(--focus-ring).

Developer spec

--focus-ring · .app-focus-target

Input focus

Developer spec

.app-input:focus-visible

Elevation & z-index

Staggered stack — higher z-index layers sit above lower ones.

--z-base(1)

--z-dropdown(50)

--z-studio(150)

--z-header(190)

--z-modal(200)

Logos

Logo lockup — header

L icon — compact mark

Lockup — on light

Maintain clear space equal to the height of the “L” mark. Do not stretch, recolor, or place on low-contrast backgrounds.

Do / Don't

Do

Add shared UI to styles/components/app-*.css
Use semantic tokens from styles/tokens/
Use canvas heading classes for in-app titles
Use .stdbutton / .altbutton for app-wide actions
Use AppListSelect for dropdown menus
Keep one filled primary per action row
Use opacity-based secondary text
Scope marketing purple to .lp2 only

Don't

Stack multiple .stdbutton fills in one row
Use global h1–h6 in app UI
Use native <select> for product UI
Add purple accents to app shell
Add new patterns to styles.css
Hardcode hex in component CSS
Use flat #bbb for secondary text

Theme API

document.documentElement.setAttribute("data-theme", "light" | "dark")
Persisted in localStorage.theme (default: dark)
.loggedout / .auth-page use a dedicated dark chrome palette
The switch on this page is preview-only — it does not change your app-wide theme.

Token reference

Live values from the preview theme (Dark). Switch theme above to compare. Section links jump to where each token is documented.

Token	Dark value	Used by
`--color`		Global text
`--text-secondary`		Secondary text
`--text-tertiary`		Tertiary text
`--bg`		Page shell
`--verylightbg`		Subtle surface
`--popupbg`		Panels / dropdowns
`--surface-chrome`		.app-glass-chrome
`--scrim-default`		.app-backdrop-scrim
`--stdbuttonbg`		.stdbutton fill
`--stdbuttoncolor`		.stdbutton text
`--hairline`		Hairline border
`--focus-ring`		Focus states
`--color-success`		Success feedback
`--color-error`		Error feedback
`--text-display-hero`		Landing hero
`--text-display-section`		Landing section titles
`--text-page-title`		Canvas page titles
`--text-section-title`		In-app sections
`--text-panel-title`		Inspector sections
`--text-panel-label`		Layers / panel labels
`--text-subsection-title`		Nested settings blocks
`--text-chrome-title`		Top bar board name
`--text-chat-heading`		Canvas chat headings
`--control-font-size`		Canvas controls
`--control-height-md`		Top bar buttons
`--control-height-sm`		Compact controls
`--blur-sm`		Modal scrims
`--blur-md`		Site header chrome
`--blur-lg`		Canvas top bar
`--blur-xl`		Floating bars
`--backdrop-saturate-chrome`		Header saturate
`--backdrop-saturate-canvas`		Canvas top bar saturate
`--scrim-dense`		Dense overlay (no blur)
`--radius-sm`		Small corners
`--radius-md`		Inspector fields
`--radius-lg`		Top-bar controls
`--radius-full`		Toolbar, pills
`--space-2`		Tight gap
`--space-4`		Default gap
`--space-8`		Section gap
`--shadow-sm`		Subtle elevation
`--shadow-md`		Cards
`--shadow-lg`		Modals
`--z-header`		Header
`--z-modal`		Modals
`--duration-fast`		Quick transitions
`--duration-normal`		Transitions
`--ease-default`		Easing
`--font-sans`		Inter body stack
`--font-title`		Space Grotesk titles

Principles

Control decision tree

Color

Text hierarchy

Surfaces

Interactive / chrome

Semantic (feedback only)

Typography

Create anything.

In-app canvas scale

Spacing

Border radius

Shadows

Materials & blur

Motion

Buttons

Canvas-specific chrome

Form controls

Deprecated legacy

Search & selection

Feedback & status

Loading & empty

No boards yet

Modals & overlays

App screen

Generate assets

Body text

Layout & dividers

Focus & accessibility

Elevation & z-index

Logos

Do / Don't

✓Do

✕Don't

Theme API

Token reference

Do

Don't