onyx-foundation
DesignStyling foundations, CSS variables, layout grid, breakpoints, and responsive mixins for Onyx. Use when writing custom CSS, designing layouts, or ensuring theme compliance.
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Onyx Foundation & Theming
Apply Onyx styling foundations, CSS variables, responsive grid, and layout rules.
Theming & Colors
Onyx supports light and dark themes out-of-the-box. Theme switching is handled automatically.
Rule: CSS Variables Only
NEVER hardcode hex, rgb, or hsl color values. Always use semantic Onyx CSS variables (prefixed with --onyx-).
- Base backgrounds:
var(--onyx-color-base-background-tinted),var(--onyx-color-base-background-blank) - Primary brand:
var(--onyx-color-base-primary-500),var(--onyx-color-base-primary-100) - Text & icons:
var(--onyx-color-text-icons-primary-soft),var(--onyx-color-text-icons-primary-medium),var(--onyx-color-text-icons-primary-intense) - Component states:
var(--onyx-color-component-cta-default),var(--onyx-color-component-border-primary),var(--onyx-color-component-focus-primary)
Note: Access ONLY Semantic variables. Do NOT use global or component variables directly in applications.
Density
Density levels control the vertical white space and heights (base heights: Compact = 32px, Default = 40px, Cozy = 48px). Apply density via properties on supported components or by adding these CSS classes to any element:
.onyx-density-compact.onyx-density-default.onyx-density-cozy
Breakpoints
The design system defines six standard breakpoints:
2xs:320pxto576px(Max 4 columns)xs:577pxto768px(Max 8 columns)sm:769pxto992px(Max 8 columns)md:993pxto1440px(Max 12 columns)lg:1441pxto1920px(Max 12 or 16 columns)xl:1921pxand beyond (Max 12, 16, or 20 columns)
Responsive SCSS Mixins
Import "sit-onyx/breakpoints.scss" to apply media or container queries:
@use "sit-onyx/breakpoints.scss";
// Media queries (compares against whole screen width)
.my-screen-class {
@include breakpoints.screen(max, sm) {
/* styles for sm and smaller */
}
@include breakpoints.screen(min, md) {
/* styles for md and larger */
}
}
// Container queries (compares against nearest container width)
// MUST set container-type on the parent element
.my-container-class {
container-type: inline-size;
@include breakpoints.container(max, md) {
/* styles for md container and smaller */
}
@include breakpoints.container(min, lg) {
/* styles for lg container and larger */
}
}
Grid System
Onyx uses container-query-based grids. The nearest parent component with container-type: inline-size; (automatically set by OnyxPageLayout, OnyxAppLayout, OnyxSidebar) determines the active grid width.
Grid Classes
- Container:
.onyx-grid(Defines a grid container) - Spanning Columns:
.onyx-grid-span-<number>(Define exact span from 1 to 12) - Full Width:
.onyx-grid-span-full(Span all available columns) - Breakpoint-Specific Span:
.onyx-grid-<breakpoint>-span-<number>(Define column span for a specific breakpoint and larger)
Grid Margin
Apply .onyx-grid-layout manually to wrap page contents and add outer page margins if not using OnyxPageLayout.
<template>
<div class="onyx-grid">
<!-- Spans 4 cols on smaller screens, 6 on md and larger -->
<OnyxCard class="onyx-grid-span-4 onyx-grid-md-span-6">Content</OnyxCard>
<!-- Spans full width always -->
<OnyxCard class="onyx-grid-span-full">Footer / Hero</OnyxCard>
</div>
</template>
Grid Customization
Set these CSS classes on the root element of your application (e.g. OnyxAppLayout):
- Limit Max Width:
onyx-grid-max-md(max 1440px) oronyx-grid-max-lg(max 1920px) - Alignment:
onyx-grid-center(Centers the layout when screen size exceeds max width) - Max Columns (lg and beyond):
onyx-grid-lg-16(16 columns) oronyx-grid-xl-20(20 columns)
Page Layout (OnyxPageLayout)
Implement the OnyxPageLayout component as the root element on every individual page/view to ensure standardized paddings, page-level scroll behavior, and unified outer page margins.
<template>
<OnyxPageLayout>
<OnyxHeadline is="h1">Page Title</OnyxHeadline>
</OnyxPageLayout>
</template>
For recurring page elements (like sidebars, footers, or sub-navigation), wrap the OnyxPageLayout in a reusable component or a Nuxt layout.
Layout Principles & Page Anatomy
All custom layout constructions must align with the core Onyx layout guidelines:
Core Principles
- Responsive: Layouts must fluidly adapt to maintain usability and visual hierarchy across all device sizes.
- Content-Driven: Prioritize structural layout decisions based on the content's hierarchy and user needs, not vice versa.
The Four Page Anatomy Regions
- Main Navigation (
OnyxNavBar): Persistent top/left area independent of scroll containers, providing access to top-level views. - Sidebar (
OnyxSidebar): Persistent left/right sidebar used for secondary navigation or master-detail detail panels. - Page Content (
OnyxPageLayout): The flexible central area governed by the grid system and acting as the primary scroll container. - Bottom Bar (
OnyxBottomBar): Scroll-independent sticky bar at the bottom for status confirmations or primary page-level triggers.
Component Alignment Rule
- STRICT Left-Alignment: All internal component layout structures must be left-aligned to preserve scannability.
- Exception: Tables and data grids may utilize center/right alignment within specific columns depending on data type formats (e.g. numeric currencies).
Visual Rhythm & Grouping
- Spatial Grouping: Group functionally related components together using generous empty space (white space), typography, or dividers to minimize cognitive load. Ensure balanced proportions across all section distributions.
Validation & Quality Check
After writing custom layouts or styling overrides, you MUST run the following verification steps:
- CSS Variables Audit: Scan your stylesheets for any hardcoded hex, rgb, or hsl values, or direct global/component variable usages. Replace them with proper
--onyx-semantic variables. - Layout Alignment Check: Verify all custom component interiors are left-aligned (with the exception of specific table/data grid columns).
- Responsive Verification: Verify your CSS container-query selectors are properly paired with a parent
container-type: inline-size;. Ensure no breakpoint styles break responsive fluidity.