# BPL DS — Agent Instructions > Machine-readable contract for AI agents implementing UI with Be Partner DS v1.4.6. > Canonical URL: https://ds.bepartnerlabs.com/AGENTS.md > Full registry: https://ds.bepartnerlabs.com/registry/components.json --- ## Architecture ### CSS Layers (in cascade order) `@layer bp-tokens, bp-reset, bp-grid, bp-components, bp-utilities;` Tokens always lose to components. Utilities always win. ### Token Contract Reference: https://www.giorgiosaud.io/notebook/custom-properties-with-defaults Every component uses a 4-level variable chain: ``` Level 0 --figma-blue-500 Figma/Style Dictionary output. Never used directly in CSS. Level 1 --bp-primary DS base tokens on :root. Client remaps these to Figma values. Level 2 --btn-background Component public slot. Named after the CSS property it controls. Level 3 --_background Private resolver. Never override from outside. ``` ```css /* Inside the DS source */ .bp-btn { --_background: var(--btn-background, var(--bp-primary)); background-color: var(--_background); } ``` #### 5 Rules **Rule 1 — Token names match the CSS property.** `--btn-background` controls `background-color`. `--btn-border-radius` controls `border-radius`. Never use abbreviations (`--btn-bg` ❌). **Rule 2 — No state tokens.** `--btn-background-hover` is banned. Override hover by re-declaring the same Level 2 token in a state selector: ```css .my-cta { --btn-background: var(--bp-cta); } .my-cta:hover { --btn-background: var(--bp-cta-hover); } ``` **Rule 3 — Private vars use `--_` prefix.** Short property-named suffixes: `--_background`, `--_color`, `--_border`, `--_radius`, `--_padding`. Private vars live only on the component root selector. **Rule 4 — Component tokens never go on `:root`.** Global brand theming flows through Level 1 (`--bp-*`) only. Component tokens (`--btn-*`) are for per-instance exceptions on scoped selectors. **Rule 5 — Child element tokens only when documented.** Child styling is private (`--_*`) by default. Expose a Level 2 token for a child element only when there is a consumer need: `----` (e.g. `--card-link-color`). #### Global Theming Pattern Client maps Figma tokens → `--bp-*` at `:root`. Every component inherits the brand automatically: ```css /* Client :root — only touch Level 1 */ :root { --bp-primary: var(--figma-blue-500); --bp-primary-fg: var(--figma-white); } /* Per-instance exception — scoped Level 2 */ .hero__cta { --btn-background: var(--bp-color-accent); } ``` ### Responsive: Container Queries Every component root has `container-type: inline-size`. Use `@container` for breakpoints, not `@media`. Exception: full-viewport layouts (hero, header, footer) use `@media`. ### State: ARIA + Native Pseudo-classes CSS reads DOM state. JS writes it. Never toggle style classes. ```css /* ✅ CSS reads the DOM */ .bp-tabs__tab[aria-selected="true"] { color: var(--_accent); } .bp-modal[open] { opacity: 1; } /* ❌ Never */ .bp-tabs__tab.is-active { color: var(--_accent); } ``` --- ## Grid System **Root class:** `.bp-content-grid` Named-line CSS grid layout. Root class: .bp-content-grid. Zone classes go on DIRECT CHILDREN of the grid, not on the grid root itself. **Zones — add the class on the DIRECT CHILD, not on the grid root:** - `content` — no class (default), width ~72rem. Default. No class needed. All direct children land here. - `popout` — class `.popout`, width ~60rem. Add class .popout on the child. For quotes, CTAs, mid-size media. - `breakout` — class `.breakout`, width ~90rem. Add class .breakout on the child. For grids, covers, video. - `full-width` — class `.full-width`, width 100vw. Add class .full-width on the child. Sub-content still inherits grid columns. **Public API tokens** (set on `.bp-content-grid` or a parent): - `--padding-inline` — Horizontal gutter. Default: clamp(1.25rem, 1vw + 1rem, 2rem) (default: `clamp(1.25rem, 1vw + 1rem, 2rem`) - `--content-max-width` — Max width of the content zone. Default: 72rem (1152px) (default: `72rem`) - `--popout-max-width` — Max width of the popout zone. Default: 60rem (960px) (default: `60rem`) - `--breakout-max-width` — Max width of the breakout zone. Default: 90rem (1440px) (default: `90rem`) **Canonical HTML:** ```html

Default content zone — no class needed

Popout zone
Breakout zone
Full-width zone
``` --- ## Theming: Prefix Override Client implementations can replace the `--bp-` prefix with their own brand prefix on base tokens. This allows full white-labeling without touching any component CSS. **What you can replace:** | Scope | How | |-------|-----| | Base tokens on `:root` | Redefine `--bp-*` as `---*` in your own `:root` block, then map them back | | Grid layout tokens | Override directly — grid tokens (`--padding-inline`, `--content-max-width`, etc.) have no prefix, they're already your surface | **What you must NOT replace:** | Scope | Why | |-------|-----| | Component public tokens (`--btn-*`, etc.) | These resolve via the 3-level chain; override them per-component, not globally | | Private vars (`--_*`) | Internal — undefined behavior if overridden | **Pattern — full prefix override:** ```css /* Client maps their tokens to the bp- surface */ :root { --bp-primary: var(--acme-brand-500); --bp-primary-fg: var(--acme-white); --bp-color-bg: var(--acme-neutral-100); /* ... map every --bp-* you use */ } ``` Every component picks up the new values automatically through the 3-level chain — no component CSS changes needed. --- ## Rules - Copy component HTML from `https://ds.bepartnerlabs.com/components//` verbatim - Customize via `---*` properties on a CSS class. Never use `style=""` - Never modify DS source CSS - Use correct semantic elements: ` ``` --- ### Dropdown Menu (`.bp-dropdown`) Accessible menu anchored to a trigger — CSS for appearance, a small Web Component for keyboard navigation and focus management. **Base pattern:** ```html ``` --- ## Components Reference-only. Use token count to judge whether a component is worth fetching before using it. ### Alert (`.bp-alert`) — [docs](https://ds.bepartnerlabs.com/components/alert/) Inline feedback message for persistent contextual notices — four semantic variants, optional dismiss, and left-accent stripe.. 12 public tokens. ### Avatar (`.bp-avatar`) — [docs](https://ds.bepartnerlabs.com/components/avatar/) Circular user image using a native img element — with CSS-only initials fallback, size variants, and composable avatar groups.. 11 public tokens. ### Badge (`.bp-badge`) — [docs](https://ds.bepartnerlabs.com/components/badge/) Inline label for status, counts, and categories — semantic color variants with solid, subtle, and outline styles.. 4 public tokens. ### Breadcrumb (`.bp-breadcrumb`) — [docs](https://ds.bepartnerlabs.com/components/breadcrumb/) Navigation trail showing the user's location in a hierarchy — semantic `