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Nitro Kitv2.0.0.alpha.4

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IntroductionGalleryAgent guideGalleryHuman guideGalleryColorsFoundations · ThemeTypographyFoundations · ThemeSpacing & sizingFoundations · ThemeEffectsFoundations · ThemeButtonComponents · ActionsButton groupComponents · ActionsButton toComponents · ActionsAppearance pickerComponents · FormsCheckboxComponents · FormsCheckbox groupComponents · FormsComboboxComponents · FormsControl groupComponents · FormsDropzoneComponents · FormsFieldComponents · FormsField groupComponents · FormsFieldsetComponents · FormsInputComponents · FormsLabelComponents · FormsRadio buttonComponents · FormsRadio button groupComponents · FormsRich text areaComponents · FormsSelectComponents · FormsSwitchComponents · FormsTextareaComponents · FormsCommand paletteComponents · OverlaysDialogComponents · OverlaysDropdownComponents · OverlaysSheetComponents · OverlaysTooltipComponents · OverlaysAlertComponents · FeedbackEmpty stateComponents · FeedbackToastComponents · FeedbackAccordionComponents · Data displayAvatarComponents · Data displayAvatar stackComponents · Data displayBadgeComponents · Data displayDetails tableComponents · Data displayIconComponents · Data displayProgressive imageComponents · Data displayStat gridComponents · Data displayTableComponents · Data displayTypesetComponents · Data displayPaginationComponents · NavigationPagination barComponents · NavigationTabsComponents · NavigationToolbarComponents · NavigationCardComponents · LayoutContainerComponents · LayoutFlexComponents · LayoutGridComponents · LayoutApplication navigationComponents · ApplicationApplication shellComponents · ApplicationAuthentication shellComponents · ApplicationDanger zoneComponents · ApplicationData sectionComponents · ApplicationForm sectionComponents · ApplicationPage headerComponents · ApplicationSettings layoutComponents · ApplicationSign inCompositions · Access & onboardingPassword resetCompositions · Access & onboardingEmail verificationCompositions · Access & onboardingInvitation acceptanceCompositions · Access & onboardingAccount creationCompositions · Access & onboardingAccount securityCompositions · Access & onboardingWorkspace onboardingCompositions · Access & onboardingBranched onboardingCompositions · Access & onboardingWorkspace dashboardCompositions · Workspace & organizationWorkspace settingsCompositions · Workspace & organizationWorkspace usersCompositions · Workspace & organizationTeam managementCompositions · Workspace & organizationAPI credentialsCompositions · Workspace & organizationOrganization overviewCompositions · Workspace & organizationOrganization settingsCompositions · Workspace & organizationTeam activityCompositions · Workspace & organizationTeam memberCompositions · Workspace & organizationSubscription billingCompositions · Billing & commerceCheckout and paymentCompositions · Billing & commerceCheckout resultsCompositions · Billing & commerceData resource overviewCompositions · Data & operationsData resource activityCompositions · Data & operationsData resource settingsCompositions · Data & operationsProduct resource lifecycleCompositions · Data & operationsAPI webhooksCompositions · Data & operationsIntegration managementCompositions · Data & operationsFile uploadsCompositions · Data & operationsActivity and audit logCompositions · Data & operationsChangelogCompositions · Product & supportHelp centerCompositions · Product & supportSystem status and errorsCompositions · Product & supportProduct landingCompositions · MarketingPublic pricingCompositions · MarketingProduct featuresCompositions · MarketingPublic contactCompositions · MarketingSidebar operations applicationCompositions · Complete applicationsTopbar media applicationCompositions · Complete applicationsHybrid account applicationCompositions · Complete applications

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  • Introduction
  • Agent guide
  • Human guide
  • Foundations
    • Colors
    • Typography
    • Spacing & sizing
    • Effects
  • Actions
    • Button
    • Button group
    • Button to
  • Forms
    • Appearance picker
    • Checkbox
    • Checkbox group
    • Combobox
    • Control group
    • Dropzone
    • Field
    • Field group
    • Fieldset
    • Input
    • Label
    • Radio button
    • Radio button group
    • Rich text area
    • Select
    • Switch
    • Textarea
  • Overlays
    • Command palette
    • Dialog
    • Dropdown
    • Sheet
    • Tooltip
  • Feedback
    • Alert
    • Empty state
    • Toast
  • Data display
    • Accordion
    • Avatar
    • Avatar stack
    • Badge
    • Details table
    • Icon
    • Progressive image
    • Stat grid
    • Table
    • Typeset
  • Navigation
    • Pagination
    • Pagination bar
    • Tabs
    • Toolbar
  • Layout
    • Card
    • Container
    • Flex
    • Grid
  • Application
    • Application navigation
    • Application shell
    • Authentication shell
    • Danger zone
    • Data section
    • Form section
    • Page header
    • Settings layout
  • Access & onboarding
    • Sign in
    • Password reset
    • Email verification
    • Invitation acceptance
    • Account creation
    • Account security
    • Workspace onboarding
    • Branched onboarding
  • Workspace & organization
    • Workspace dashboard
    • Workspace settings
    • Workspace users
    • Team management
    • API credentials
    • Organization overview
    • Organization settings
    • Team activity
    • Team member
  • Billing & commerce
    • Subscription billing
    • Checkout and payment
    • Checkout results
  • Data & operations
    • Data resource overview
    • Data resource activity
    • Data resource settings
    • Product resource lifecycle
    • API webhooks
    • Integration management
    • File uploads
    • Activity and audit log
  • Product & support
    • Changelog
    • Help center
    • System status and errors
  • Marketing
    • Product landing
    • Public pricing
    • Product features
    • Public contact
  • Complete applications
    • Sidebar operations application
    • Topbar media application
    • Hybrid account application

Container

Centered content maximums backed by the existing public width tokens.

Source
app/components/nitro_kit/container.rb
API
NitroKit::Container.new(size: :sm | :md | :lg | :xl); omit Container for full-width content

Content widths

Four existing content tokens provide centered maximum widths without arbitrary CSS values. The preview column is narrower than the lg and xl maximums, so those two clamp to the column here; widen the Responsive tab to see them diverge.

Every size

SM content boundary

Uses --nk-content-sm; the surrounding application still owns available width.

MD content boundary

Uses --nk-content-md; the surrounding application still owns available width.

LG content boundary

Uses --nk-content-lg; the surrounding application still owns available width.

XL content boundary

Uses --nk-content-xl; the surrounding application still owns available width.
ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
render NitroKit::Flex.new(dir: :col, gap: 6, align: :stretch, id: "gallery-container-size-stack") do
  NitroKit::Container::SIZES.each do |size|
    render NitroKit::Container.new(size:, id: "gallery-container-size-#{size}") do
      render NitroKit::Card.new(id: "gallery-container-size-#{size}-card") do |card|
        card.title("#{size.to_s.upcase} content boundary", level: 4)
        card.body("Uses --nk-content-#{size}; the surrounding application still owns available width.")
      end
    end
  end
end

Full-width boundary

Full width is ordinary direct composition, not a fifth size or a special escape.

Omit Container

API
render NitroKit::Card.new(...) # no Container wrapper

Full available width

No data-nk=container ancestor is emitted for this surface.
ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
render NitroKit::Card.new(id: "gallery-container-full-width-card") do |card|
  card.title("Full available width", level: 4)
  card.body("No data-nk=container ancestor is emitted for this surface.")
end

Content pressure

A content boundary accepts empty, single, multiple, and long direct Phlex children.

Empty, one, and many

Empty
One
Many
Queued operation 1
Waiting for deterministic processing.
Queued operation 2
Waiting for deterministic processing.
Queued operation 3
Waiting for deterministic processing.
Queued operation 4
Waiting for deterministic processing.
Queued operation 5
Waiting for deterministic processing.
Queued operation 6
Waiting for deterministic processing.
ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
sample("Empty", slug: "empty") do
  render NitroKit::Container.new(size: :sm, id: "gallery-container-empty")
end
sample("One", slug: "one") do
  render NitroKit::Container.new(size: :sm, id: "gallery-container-one") do
    render NitroKit::Button.new(
      "Intrinsic child",
      id: "gallery-container-one-action",
      variant: :primary
    )
  end
end
sample("Many", slug: "many") do
  render NitroKit::Container.new(size: :md, id: "gallery-container-many") do
    render NitroKit::Flex.new(dir: :col, gap: 2, align: :stretch) do
      6.times do |index|
        render NitroKit::Alert.new(id: "gallery-container-many-#{index + 1}") do |alert|
          alert.title("Queued operation #{index + 1}")
          alert.description("Waiting for deterministic processing.")
        end
      end
    end
  end
end

Long readable boundary

Analytical Engines — International Research, Production, and Reliability Engineering

This account description stays inside the same readable maximum width even when customer-owned identity and operational context are substantially longer than the common case.

ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
render NitroKit::Container.new(size: :md, id: "gallery-container-long") do
  render NitroKit::Card.new(id: "gallery-container-long-card") do |card|
    card.title(
      "Analytical Engines — International Research, Production, and Reliability Engineering",
      level: 4
    )
    card.body do
      p do
        "This account description stays inside the same readable maximum width even when customer-owned " \
          "identity and operational context are substantially longer than the common case."
      end
    end
  end
end

Nested compositions

Container owns only maximum width; stacks, rows, and Grid retain their independent responsibilities.

Wide workspace collection

12 active members

Ada Lovelace

Owner · [email protected]

Grace Hopper

Admin · [email protected]

Katherine Johnson

Member · [email protected]
ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
render NitroKit::Container.new(size: :xl, id: "gallery-container-composition") do
  render NitroKit::Flex.new(dir: :col, gap: 6, align: :stretch) do
    render NitroKit::Flex.new(dir: :row, align: :center, gap: 2, justify: :between, wrap: :wrap) do
      render NitroKit::Badge.new(
        "12 active members",
        id: "gallery-container-composition-status",
        color: :success
      )
      render NitroKit::Button.new(
        "Invite teammate",
        id: "gallery-container-composition-action",
        variant: :primary
      )
    end
    render NitroKit::Grid.new(cols: "1 sm:2 lg:3", id: "gallery-container-composition-grid") do
      Gallery::Data.members.each do |member|
        render NitroKit::Card.new(id: "gallery-container-composition-#{member.id}") do |card|
          card.title(member.name, level: 4)
          card.body("#{member.role.to_s.humanize} · #{member.email}")
        end
      end
    end
  end
end

Evidence boundary

The first extraction wave stays smaller than the speculative vocabulary in the pivot plan.

Deferred names

API
No Spacer, Split, Frame, custom breakpoints, as:, or arbitrary CSS-value APIs
Three layout names remain deliberately unimplemented
Spacer has no elastic-gap evidence and current rows use justify. Split appears in only one unsettled settings candidate. Frame has no flow evidence and would conflict with Turbo Frame language.
ViewportFull width
Rubytest/dummy/app/components/gallery/components/container_page.rb
render NitroKit::Container.new(size: :lg, id: "gallery-container-deferred") do
  render NitroKit::Alert.new(id: "gallery-container-deferred-alert") do |alert|
    alert.title("Three layout names remain deliberately unimplemented")
    alert.description(
      "Spacer has no elastic-gap evidence and current rows use justify. Split appears in only one " \
        "unsettled settings candidate. Frame has no flow evidence and would conflict with Turbo Frame language."
    )
  end
end

Component contract

Constructor options, rendered root, closed vocabularies, and compound boundary for this component, exactly as shipped.

docs/component_contracts.md · NitroKit::Container

Constructor
required size:, id: nil
Root
div[data-nk=container]
Contract
Sizes sm md lg xl; centered maximum width. Omit the component for full-width content.

System rules for coding agents

Instructions for coding agents, repeated on every component page so one fetched page has enough context. Humans can usually skip this section.

test/dummy/app/components/gallery/agent_rules.rb

View agent instructions
  • Nitro Kit 2.0 is a gem-owned, Phlex-only UI system for Rails. Render components directly: render NitroKit::Button.new("Save", variant: :primary).
  • Compose Nitro components inside application-owned Phlex classes. Public initializers and declared slots are the component API; private methods are not.
  • Public options are explicit keywords, and enumerated options are closed vocabularies. Invalid names or values raise ArgumentError; this component's accepted options are in the contract above.
  • Pass native attributes through their typed boundary: html: for HTML, aria: for ARIA, and data: for application data. class and style are forbidden, including inside html:.
  • Nitro owns NitroKit::Component::RESERVED_DATA_ATTRIBUTES: data-nk, data-slot, data-variant, data-size, data-nk-escape, data-enhanced, data-state, data-disabled, data-required, data-orientation, data-presentation, data-placement, data-layout, data-side, data-field-type, data-dir, data-gap, data-align, data-justify, data-wrap, data-cols, data-mode, data-key. Do not pass them through data:. data-action, data-controller are additive and compose with Nitro behavior.
  • If an integration truly requires a class, use desperately_need_a_class:. It requires a non-blank String and marks the exception with data-nk-escape="class".
  • Every root emits data-nk; owned parts emit component-qualified data-slot values such as field-control or card-title. Select on those attributes, never on classes.
  • Customize components with documented --nk-* custom properties in an application stylesheet. Variables beginning with --_nk-* are private component mechanics.
  • Use NitroKit::Flex and NitroKit::Grid for layout. Parents own external placement and available width; components own their intrinsic geometry.
  • Preserve native elements and accessibility semantics. State is exposed through native semantics and ARIA first, and through data-state when styling or behavior also needs it.