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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

Flex

Responsive rows and columns with Tailwind-style breakpoint shorthand and closed layout values.

Source
app/components/nitro_kit/flex.rb
API
NitroKit::Flex.new(dir: "col md:row", gap: "2 md:4", align:, justify:, wrap:)

Mobile-first shorthand

Each property accepts a base value followed by the fixed sm md lg xl 2xl breakpoint prefixes; omitted breakpoints inherit the previous value.

One layout, three arrangements

API
dir: "col md:row", gap: "2 md:4 lg:6", align: "stretch md:center", justify: "start lg:between"

Production workspace

Stacks on small screens, then becomes a row without application CSS.
12 active members
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
render NitroKit::Container.new(size: :lg) do
  render NitroKit::Flex.new(
    dir: "col md:row",
    gap: "2 md:4 lg:6",
    align: "stretch md:center",
    justify: "start lg:between",
    wrap: "nowrap md:wrap",
    id: "gallery-flex-responsive"
  ) do
    render NitroKit::Card.new(id: "gallery-flex-responsive-summary") do |card|
      card.title("Production workspace", level: 4)
      card.body("Stacks on small screens, then becomes a row without application CSS.")
    end
    render NitroKit::Badge.new(
      "12 active members",
      id: "gallery-flex-responsive-status",
      color: :success
    )
    render NitroKit::Button.new(
      "Open workspace",
      id: "gallery-flex-responsive-action",
      variant: :primary
    )
  end
end

Every breakpoint and property

API
base + sm + md + lg + xl + 2xl
Region 1Region 2Region 3Region 4Region 5Region 6
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
render NitroKit::Flex.new(
  dir: "col sm:row md:row-reverse lg:col-reverse xl:row 2xl:col",
  gap: "1 sm:2 md:4 lg:8 xl:12 2xl:16",
  align: "start sm:center md:end lg:stretch xl:baseline 2xl:center",
  justify: "start sm:center md:end lg:between xl:around 2xl:evenly",
  wrap: "nowrap sm:wrap md:wrap-reverse lg:nowrap xl:wrap 2xl:wrap-reverse",
  id: "gallery-flex-breakpoints"
) do
  6.times do |index|
    render NitroKit::Badge.new(
      "Region #{index + 1}",
      id: "gallery-flex-breakpoint-#{index + 1}",
      variant: :outline
    )
  end
end

Direction

Rows, columns, and their reverse forms share one primitive and the same responsive grammar.

Every direction

Row
Item 1Item 2Item 3
Col
Item 1Item 2Item 3
Row-reverse
Item 1Item 2Item 3
Col-reverse
Item 1Item 2Item 3
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
%w[row col row-reverse col-reverse].each do |direction|
  sample(direction.humanize, slug: direction) do
    render NitroKit::Flex.new(
      dir: direction,
      gap: 2,
      align: :start,
      id: "gallery-flex-dir-#{direction}"
    ) do
      3.times do |index|
        render NitroKit::Badge.new(
          "Item #{index + 1}",
          id: "gallery-flex-dir-#{direction}-#{index + 1}",
          variant: :outline
        )
      end
    end
  end
end

Gap and alignment

Numeric gaps follow Nitro's spacing unit. Alignment includes start, center, end, stretch, and baseline.

Responsive gap

Space 1Space 2Space 3Space 4Space 5Space 6
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
render NitroKit::Flex.new(
  dir: :row,
  gap: "1 sm:2 md:4 lg:8 xl:12 2xl:16",
  align: :center,
  wrap: :wrap,
  id: "gallery-flex-gap-responsive"
) do
  6.times do |index|
    render NitroKit::Badge.new(
      "Space #{index + 1}",
      id: "gallery-flex-gap-responsive-#{index + 1}",
      color: :info
    )
  end
end

Every alignment

Start
Short
Taller surface

A second line makes cross-axis alignment visible.

Center
Short
Taller surface

A second line makes cross-axis alignment visible.

End
Short
Taller surface

A second line makes cross-axis alignment visible.

Stretch
Short
Taller surface

A second line makes cross-axis alignment visible.

Baseline
Short
Taller surface

A second line makes cross-axis alignment visible.

ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
%w[start center end stretch baseline].each do |alignment|
  sample(alignment.humanize, slug: alignment) do
    render NitroKit::Flex.new(
      dir: :row,
      gap: 2,
      align: alignment,
      id: "gallery-flex-align-#{alignment}"
    ) do
      render NitroKit::Card.new do |card|
        card.body("Short")
      end
      render NitroKit::Card.new do |card|
        card.body do
          strong { "Taller surface" }
          p { "A second line makes cross-axis alignment visible." }
        end
      end
    end
  end
end

Distribution and wrapping

Justification and wrapping remain independent, responsive decisions.

Every justification

Start
Center
End
Between
Around
Evenly
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
%w[start center end between around evenly].each do |justification|
  sample(justification.humanize, slug: justification) do
    render NitroKit::Flex.new(
      dir: :row,
      gap: 2,
      align: :center,
      justify: justification,
      id: "gallery-flex-justify-#{justification}"
    ) do
      render NitroKit::Button.new("Previous", size: :sm)
      render NitroKit::Button.new("Continue", size: :sm, variant: :primary)
    end
  end
end

Every wrap mode

Nowrap
Wrap
Wrap-reverse
ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
%w[nowrap wrap wrap-reverse].each do |wrap|
  sample(wrap.humanize, slug: wrap) do
    render NitroKit::Container.new(size: :sm) do
      render NitroKit::Flex.new(
        dir: :row,
        gap: 2,
        align: :center,
        wrap:,
        id: "gallery-flex-wrap-#{wrap}"
      ) do
        8.times do |index|
          render NitroKit::Button.new("Environment #{index + 1}", size: :sm)
        end
      end
    end
  end
end

Application composition

Responsive properties combine for familiar headers and action regions without utility classes.

Workspace heading

Operational

Analytical Engines

International Research, Production, and Reliability Engineering

ViewportFull width
Rubytest/dummy/app/components/gallery/components/flex_page.rb
render NitroKit::Container.new(size: :xl) do
  render NitroKit::Flex.new(
    dir: "col lg:row",
    gap: "4 lg:6",
    align: "stretch lg:center",
    justify: "start lg:between",
    id: "gallery-flex-composition"
  ) do
    render NitroKit::Flex.new(dir: :col, gap: 1, align: :start) do
      render NitroKit::Badge.new("Operational", color: :success)
      h3 { "Analytical Engines" }
      p { "International Research, Production, and Reliability Engineering" }
    end
    render NitroKit::Flex.new(
      dir: :row,
      gap: 2,
      align: :center,
      justify: :end,
      wrap: :wrap,
      id: "gallery-flex-composition-actions"
    ) do
      render NitroKit::Button.new("View activity")
      render NitroKit::Button.new("Create deployment", variant: :primary)
    end
  end
end

Component contract

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

docs/component_contracts.md · NitroKit::Flex

Constructor
required dir:; gap: 4, align: :start, justify: :start, wrap: :nowrap, id: nil
Root
div[data-nk=flex]
Contract
Direction, gap, alignment, justification, and wrapping accept scalar or responsive values. Direct content; empty content is valid.

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.