Svelte 5 components for the Marwes design system with default styling, typed theme tokens, accessibility contracts, and AI-readable semantics.

Marwes Design System - Svelte

Svelte 5 components with default Marwes styling, typed theme tokens, accessibility contracts, and AI-readable semantics built in.

Svelte 5 • TypeScript-first • Default CSS included • ThemeInput • Google Fonts DX • Purpose components

Documentation • Svelte Storybook • GitHub

Why Use It

Marwes gives Svelte apps a ready design-system base without requiring custom CSS setup or local component forks.

• One package for Svelte apps: components, provider, default preset CSS, theme helpers, and typed props.
• Svelte-native binding: common controls support bind:value and bind:checked while preserving Marwes semantic contracts.
• Runes-first: built entirely on Svelte 5 runes ($props, $state, $derived, $effect, $bindable) — no legacy stores or lifecycle hooks.
• Consequential theming: a ThemeInput object changes colors, fonts, radius, density, typography, and component visuals through shared CSS variables.
• Purpose components: SubmitButton, CancelButton, and DestructiveButton make intent machine-readable so tests, audits, and AI agents can handle actions safely.
• Shared core contracts: every Svelte component is backed by the same framework-agnostic recipes, a11y mapping, and theme shape used by React and Vue.

Package Map

For a Svelte app, install this package first. It includes the Svelte adapter, loads the default preset CSS, and re-exports the core theme helpers you normally need.

| Package | Use it when | | --- | --- | | @marwes-ui/svelte | You are building a Svelte app. | | @marwes-ui/react | You are building a React app instead. | | @marwes-ui/vue | You are building a Vue app instead. | | @marwes-ui/core | You are building adapters, tests, tooling, or framework-agnostic integrations. | | @marwes-ui/presets | You need standalone preset CSS or preset theme exports. |

This split keeps installation simple for app teams while giving humans and AI agents clear package boundaries: adapters render, core defines contracts, presets style.

Install

pnpm add @marwes-ui/svelte

No preset CSS import is needed. @marwes-ui/svelte depends on @marwes-ui/presets and loads the default Marwes CSS automatically.

Quick Start

<script lang="ts">
  import {
    Button,
    ButtonVariant,
    Checkbox,
    Input,
    MarwesProvider,
    SubmitButton,
  } from "@marwes-ui/svelte"

  let email = $state("")
  let subscribed = $state(false)
</script>

<MarwesProvider>
  <Input bind:value={email} placeholder="Email" ariaLabel="Email" />
  <Checkbox bind:checked={subscribed} ariaLabel="Subscribe" />
  <Button variant={ButtonVariant.secondary}>Preview</Button>
  <SubmitButton>Save</SubmitButton>
</MarwesProvider>

Style App-Owned UI

Marwes components pick up provider tokens automatically. Your own Svelte styling can use the same tokens through scoped styles, global CSS, or mwThemeVars in script-driven style objects.

<script lang="ts">
  import { Button, ButtonVariant, MarwesProvider, mwThemeVars } from "@marwes-ui/svelte"

  const panelStyle = `
    padding: ${mwThemeVars.spacing.sp24};
    background: ${mwThemeVars.color.surface};
    color: ${mwThemeVars.color.text};
    border: 1px solid ${mwThemeVars.color.border};
    border-radius: ${mwThemeVars.ui.radius};
  `
</script>

<MarwesProvider>
  <main class="app-shell">
    <aside class="primary-callout">Launch workspace</aside>
    <section style={panelStyle}>
      <Button variant={ButtonVariant.primary}>Save</Button>
    </section>
  </main>
</MarwesProvider>

<style>
  .app-shell {
    min-height: 100dvh;
    padding: var(--mw-spacing-sp-24);
    color: var(--mw-color-text);
    background: var(--mw-color-background);
  }

  .primary-callout {
    background: var(--mw-color-primary-base);
    color: var(--mw-color-primary-label);
  }
</style>

Use Typed Components

Import components, enums, and prop types from the same package. The values line up with the same core recipes and preset CSS.

<script lang="ts">
  import {
    BadgeVariant,
    Button,
    ButtonSize,
    ButtonVariant,
    Card,
    H1,
    InputField,
    Paragraph,
    Spacer,
    Spacings,
    StatusBadge,
    SubmitButton,
    type ButtonProps,
    type H1Props,
    type InputFieldProps,
    type ParagraphProps,
  } from "@marwes-ui/svelte"
</script>

<Card title="Project setup">
  <StatusBadge variant={BadgeVariant.success}>Ready</StatusBadge>
  <Spacer spacing={Spacings.sp16} />
  <H1 size="h2">Launch workspace</H1>
  <Paragraph size="md">
    Components share theme tokens, typed variants, spacing, and semantic metadata.
  </Paragraph>
  <InputField
    label="Email"
    helperText="Used for project notifications."
    input={{ type: "email", placeholder: "[email protected]" }}
  />
  <Spacer spacing={Spacings.sp24} />
  <Button variant={ButtonVariant.primary} size={ButtonSize.md}>Create project</Button>
  <SubmitButton>Save changes</SubmitButton>
</Card>

Available Components

Provider and hooks:

• MarwesProvider
• useTheme
• useToast

Actions and buttons:

• Button
• PrimaryButton, SecondaryButton, TextButton, SuccessButton
• SubmitButton, CancelButton, CreateButton, DestructiveButton
• LinkButton, SaveButton, ConfirmButton, VerifyButton
• EditButton, CloseButton, RefreshButton
• UploadButton, DownloadButton, CopyButton
• SearchButton, FilterButton, SortButton, DropdownButton

Forms and inputs:

• Input, Textarea, Select, RichText, InputOtp
• InputField, TextareaField, SelectField, RichTextField
• DropdownField, SearchField, PasswordField, EmailField
• DateOfBirthField, ZipCodeField, PhoneField, URLField, CurrencyField
• Checkbox, CheckboxField, CheckboxGroupField
• Radio, RadioGroupField, YesNoRadioGroup, RatingRadioGroup, OptionRadioGroup
• Switch, SwitchField, FeatureToggle, PreferenceSwitch, PermissionSwitch
• Slider, SliderField, VolumeSlider, BrightnessSlider, RadiusSlider

Content and layout:

• Card, ProductCard, ProfileCard, StatCard
• H1, H2, H3, Paragraph
• Spacer, Spacing, Divider
• Icon
• Avatar, AvatarBadge, AvatarGroup, ProfileAvatar, PresenceAvatar, TeamAvatarGroup

Feedback and overlays:

• Badge, BadgeGroup, StatusBadge, PriorityBadge, NotificationBadge
• Spinner, ButtonSpinner, EmptyStateSpinner
• Toast, ToastContainer, ToastProvider
• SuccessToast, ErrorToast, WarningToast, InfoToast
• Tooltip, TooltipGroup
• Dialog, DialogModal, ConfirmDialog, DestructiveDialog, InfoDialog
• Accordion, AccordionField, FAQAccordion, SettingsAccordion, SectionsAccordion
• Tab, TabGroup, TabPanel, NavigationTabs, ContentTabs, SettingsTabs

Typed tokens and helpers:

• ThemeInput, ThemeMode, Density, ToneName
• mwAvailableFonts, mwGoogleFontFamilies, mwFontFallbacks, createFontStack
• mwThemeVars, mwThemeVarNames, mwStyledTheme, mwVar
• ButtonVariant, ButtonSize, ButtonAction
• BadgeVariant, AvatarSize, AvatarType, SwitchSize, IconName, Spacings

Theme In Seconds

The default Marwes theme is already active. If you already have a good-looking design library or brand system, pass a small typed ThemeInput override instead of rebuilding component CSS.

<script lang="ts">
  import { MarwesProvider, mwAvailableFonts, type ThemeInput } from "@marwes-ui/svelte"

  const brandTheme = {
    color: {
      primary: "#2457FF",
      danger: "#D90429",
      success: "#15803D",
      warning: "#D97706",
      background: "#F8FAFC",
      surface: "#FFFFFF",
      surfaceElevated: "#FFFFFF",
      text: "#111827",
      textMuted: "#4B5563",
      border: "#D1D5DB",
      focus: "#2457FF",
    },
    font: {
      primary: mwAvailableFonts.Poppins,
      secondary: mwAvailableFonts.Lora,
    },
    ui: {
      radius: 10,
      density: "comfortable",
    },
  } satisfies ThemeInput
</script>

<MarwesProvider theme={brandTheme}>
  <slot />
</MarwesProvider>

The provider resolves ThemeInput into --mw-* CSS variables. Preset CSS consumes those variables across the full component system.

Marwes is designed to look great from the beginning. Start with the default preset, then override only the colors, fonts, radius, or density that belong to your product. Unspecified values keep the polished Marwes defaults.

Light And Dark Mode

MarwesProvider can own the active mode for the app. Use ThemeMode.light and ThemeMode.dark instead of string literals, then read or change the active mode with useThemeMode() anywhere under the provider. Every component under the provider receives the matching --mw-* variables and mw-theme--light / mw-theme--dark class.

<script lang="ts">
  import { Button, ButtonVariant, ThemeMode, useThemeMode } from "@marwes-ui/svelte"

  const { mode, toggleMode } = useThemeMode()
</script>

<Button variant={ButtonVariant.secondary} onclick={toggleMode}>
  Use {mode === ThemeMode.dark ? ThemeMode.light : ThemeMode.dark} mode
</Button>

<script lang="ts">
  import { MarwesProvider, ThemeMode } from "@marwes-ui/svelte"
</script>

<MarwesProvider defaultMode={ThemeMode.light}>
  <slot />
</MarwesProvider>

defaultMode sets the initial uncontrolled mode. toggleMode() updates the provider, so Marwes components, preset CSS, and custom app styles that use --mw-* variables all move together without duplicating local theme state.

System And Persisted Preference

mode is always the rendered visual mode: ThemeMode.light or ThemeMode.dark. preference is the app or user choice: ThemeMode.light, ThemeMode.dark, or "system". Use preference and defaultPreference when your UI needs a system option; keep using mode, defaultMode, and onModeChange when you only need concrete light/dark compatibility.

<script lang="ts">
  import { Button, ButtonVariant, ThemeMode, useThemeMode } from "@marwes-ui/svelte"

  const { mode, preference, systemMode, isSystem, setPreference, setMode } = useThemeMode()
</script>

<p>Rendering {mode}; preference is {preference}; system is {systemMode}.</p>
<Button variant={ButtonVariant.secondary} onclick={() => setPreference("system")}>
  Use system
</Button>
<Button variant={ButtonVariant.secondary} onclick={() => setMode(ThemeMode.dark)}>
  Use dark
</Button>
{#if isSystem}
  <span>Following system</span>
{/if}

<script lang="ts">
  import { MarwesProvider } from "@marwes-ui/svelte"
</script>

<MarwesProvider defaultPreference="system" storageKey="marwes-theme" enableSystem>
  <slot />
</MarwesProvider>

useThemeMode().mode never returns "system"; it is always the concrete mode Marwes rendered. useThemeMode().preference returns the active app/user preference, and setPreference("system") is the system-capable setter. setMode(mode) remains a concrete light/dark convenience.

storageKey is opt-in and defaults to false. Storage reads and writes are failure-safe, so private browsing or unavailable storage will fall back to normal provider state. enableSystem defaults to true; set it to false to avoid matchMedia detection and resolve "system" through the light fallback.

Root Target Sync

By default Marwes keeps theme state scoped to the provider element. If your app shell also needs the resolved mode on html or body, set target and attribute:

<MarwesProvider
  defaultPreference="system"
  storageKey="marwes-theme"
  target="html"
  attribute="class"
  disableTransitionOnChange
>
  <slot />
</MarwesProvider>

target can be "provider", "html", or "body". attribute can be "class", "data-theme", or "data-mode". Class mode only adds the active light / dark class and removes the opposite one; unrelated classes are preserved.

SvelteKit SSR

Use createMarwesThemeStyle() and createMarwesThemeScript() when a server-rendered app needs the correct light or dark variables before hydration. Import from the /ssr subpath:

import { createMarwesThemeScript, createMarwesThemeStyle } from "@marwes-ui/svelte/ssr"

Read the theme SSR no-flash guide for SvelteKit setup, CSP nonces, custom light/dark themes, and stored/system preference behavior.

Custom Styling Tokens

MarwesProvider resolves ThemeInput into --mw-* CSS variables. Marwes components and preset CSS consume those variables automatically. The custom styling token helpers let app-owned Svelte styles use the same provider-scoped values.

Svelte style blocks can consume provider variables directly:

<style>
  .panel {
    padding: var(--mw-spacing-sp-24);
    color: var(--mw-color-text);
    background: var(--mw-color-surface);
    border-radius: var(--mw-ui-radius);
  }
</style>

For script-driven style objects, import the core helpers:

• mwThemeVars returns CSS var(...) references for inline styles and config files.
• mwThemeVarNames returns raw custom property names for assigning provider-scoped overrides.
• mwVar() wraps custom --mw-* names when the named token object does not cover a case.

import { mwThemeVarNames, mwThemeVars, mwVar } from "@marwes-ui/svelte"

const panelStyle = `
  padding: ${mwThemeVars.spacing.sp24};
  color: ${mwThemeVars.color.text};
  outline-color: ${mwVar("--mw-color-focus", "#2457FF")};
`

Keep the APIs separate:

• Use Spacings.sp24 for Marwes spacing props such as <Spacer spacing={Spacings.sp24} />.
• Use mwThemeVars.spacing.sp24 for custom CSS values.
• Use mwThemeVarNames.spacing.sp24 when assigning or inspecting a CSS custom property name.
• Use useTheme() when Svelte logic needs resolved runtime values such as "#2457FF".

Svelte Binding Conventions

• Text-like controls support bind:value through $bindable().
• Checkboxes support bind:checked and oncheckedchange.
• Switches fire oncheckedchange callbacks.
• Dialog modals support bind:open for two-way open state.
• Snippets replace React render props — use {#snippet footer({ close })}...{/snippet} for dialog footers and similar patterns.

Prefer bind: in normal Svelte app code unless you specifically need callback-style wiring.

Google Fonts DX

Most Google Font use cases only need mwAvailableFonts; no fontLoading prop is needed.

<script lang="ts">
  import { MarwesProvider, mwAvailableFonts, type ThemeInput } from "@marwes-ui/svelte"

  const fontTheme = {
    font: {
      primary: mwAvailableFonts.Poppins,
      secondary: mwAvailableFonts.Lora,
    },
  } satisfies ThemeInput
</script>

<MarwesProvider theme={fontTheme}>
  <slot />
</MarwesProvider>

For self-hosted or licensed fonts, use BrandSans, BrandSerif, BrandMono, or createFontStack().

Purpose Components

Prefer purpose components for common actions. They lock UX intent and emit AI-readable metadata, so the component is not just "a button with red styling" but a known action with known risk.

<script lang="ts">
  import {
    CancelButton,
    CreateButton,
    DestructiveButton,
    SubmitButton,
  } from "@marwes-ui/svelte"
</script>

<CancelButton>Cancel</CancelButton>
<CreateButton>Create</CreateButton>
<SubmitButton>Save</SubmitButton>
<DestructiveButton>Delete</DestructiveButton>

That matters for agentic workflows. A human, test, or AI agent can inspect the DOM and see that a destructive button requires confirmation before activation:

<button
  data-component="button"
  data-purpose="destructive"
  data-action="delete"
  data-destructive="true"
  data-confirmation-required="true"
>
  Delete
</button>

An agent can then follow a safer rule: if data-confirmation-required="true", ask the user before clicking. A test can assert the same behavior without guessing from the label "Delete" or from a red color.

Why It Is Accessible

Marwes Svelte components are accessible because the adapter renders a shared core contract, not because each component hand-rolls ARIA in isolation.

• Core recipes produce typed a11y output for roles, labels, described-by wiring, invalid state, disabled state, and semantic metadata.
• Svelte components prefer native DOM controls first: button, input, select, textarea, hr, and standard form wiring.
• Field components connect visible labels, helper text, and errors through id, for, aria-describedby, aria-invalid, and polite error announcements.
• Coordinated widgets carry explicit contracts: tabs wire tablist/tab/tabpanel, dialogs own dialog semantics, toasts expose live-region behavior, and purpose buttons expose risk metadata.
• Storybook accessibility smoke checks run through the Storybook a11y addon for the promoted Svelte families, and shared contract tests keep Svelte aligned with React and Vue.

Example:

<script lang="ts">
  import { InputField } from "@marwes-ui/svelte"
</script>

<InputField
  label="Email"
  helperText="Used for receipts."
  error="Enter a valid email."
  input={{ type: "email", placeholder: "[email protected]" }}
/>

That contract resolves to DOM wiring like:

<label for="email">Email</label>
<input
  id="email"
  type="email"
  aria-describedby="email-helper email-error"
  aria-invalid="true"
>
<p id="email-helper">Used for receipts.</p>
<p id="email-error" aria-live="polite">Enter a valid email.</p>

The important part is that the same label, helper, error, and invalid contract is tested at the shared contract layer and then applied by the Svelte adapter.

Package Boundaries

• @marwes-ui/core owns recipes, theme resolution, a11y mapping, and semantic metadata.
• @marwes-ui/presets owns default preset CSS.
• @marwes-ui/svelte owns Svelte rendering and provider behavior.

Scripts

pnpm --filter @marwes-ui/svelte build
pnpm --filter @marwes-ui/svelte test:typecheck
pnpm --filter @marwes-ui/svelte test

Related Docs

• Docs index
• Svelte adapter guide
• Architecture
• Figma to Marwes