bitvid/docs/design-system.md

bitvid Design System Primitives

bitvid's visual language is now powered by Tailwind utilities backed by our design tokens. This document lists the primitives available via css/tailwind.source.css, how they behave across states, and when to mix them with Tailwind utilities.

All templates and embeds must load css/tailwind.generated.css; that compiled bundle is the only stylesheet shipped with the app. Remove any lingering references to legacy tailwind.min.css assets when porting surfaces into the design system.

Runtime contract

The design system is now the canonical styling path across bitvid—there is no runtime flag or rollback toggle. Every template renders with data-ds="new" on its root container, and controllers always receive the "new" mode from the designSystem context (see js/designSystem.js). When migrating surfaces, ensure their root nodes include data-ds so the entrypoint can stamp the attribute during bootstrap.

Dynamic runtime styling

Inline styles are blocked in production builds, so runtime components that need bespoke coordinates or measurements must route their overrides through js/designSystem/dynamicStyles.js.

• registerScope(id, selectors) creates (or reuses) a constructable stylesheet when supported, allocates a unique identifier, and injects empty rules scoped to [data-ds-style-id="<id>"]. Callers attach the attribute to any element that should inherit those rules.
• setVariables(id, tokens) updates CSS custom properties on the registered scope. Pass CSS variable names ("--floating-fallback-top") and string or number values—setVariables handles serialization and removes entries when they resolve to empty strings.
• releaseScope(id) removes the generated rules and frees the identifier. Always invoke it from component teardown paths to avoid leaking rules between renders.

The floating panel utility and design-system metrics both lean on this helper:

• createFloatingPanelStyles assigns each popover a unique scope and publishes fallback coordinates through CSS variables instead of mutating .style. Positioning logic reads and writes the same API, and teardown releases the scope before removing dataset attributes.
• readDesignTokenAsPixels measures non-px/rem tokens with an offscreen probe that ships in core CSS (.ds-metric-probe). The probe is registered through the helper so dynamic lengths are fed into --ds-metric-probe-length without touching inline styles.

When introducing a new runtime feature that requires dynamic styling:

1. Register a dedicated scope during setup and attach the returned attribute to the relevant DOM node.
2. Update custom properties with setVariables instead of touching .style or appending <style> tags.
3. Clean up by calling releaseScope when the component unmounts.
4. Prefer reusable primitives (like .ds-metric-probe) for offscreen measurement or layout shims so multiple components can share the same CSS.

Typography & Layout Tokens

Small-type utilities and modal geometry are now backed by dedicated semantic tokens in css/tokens.css. The scale introduces --font-size-4xs (0.65rem), --font-size-3xs (0.6875rem), --font-size-2xs (0.7rem), and --tracking-extra-wide (0.2em) alongside modal measurements such as --modal-shell-max-height, --modal-sheet-max-height, --modal-body-max-height, --modal-pane-max-height, and --profile-history-max-height. Tailwind exposes the tokens through utility aliases including text-4xs, text-3xs, text-2xs, tracking-extra-wide, max-h-modal-shell, max-h-modal-sheet, max-h-modal-body, max-h-modal-pane, and max-h-profile-history. Use these utilities instead of arbitrary values so future scale adjustments can ship from a single source of truth.

Migration notes

• Replace literal classes such as text-[11px], text-[0.7rem], and text-[0.65rem] with the new semantic helpers (text-3xs, text-2xs, text-4xs). The controller logic for saved profiles and modal renderers has been updated to follow the same pattern.
• Swap bespoke tracking overrides (for example, tracking-[0.2em]) to tracking-extra-wide so the widened CTA headings stay consistent across themes.
• Move modal shells and scroll containers off arbitrary max-h-[...] utilities in favour of max-h-modal-shell, max-h-modal-sheet, max-h-modal-body, max-h-modal-pane, and max-h-profile-history.
• Keep the legacy search strings (like text-[11px]) in regression checklists—repositories should no longer include those selectors after migrating a template or controller.

Tailwind arbitrary values lint

Run npm run lint:tailwind-brackets after touching markup or prose that embeds HTML. The lint walks .html, .njk, and .md sources and fails when Tailwind's bracket syntax introduces hard-coded measurements (text-[11px], max-w-[18rem], etc.).

• Prefer the semantic utilities shipped alongside the tokens (max-w-popover-safe, max-h-modal-shell, text-3xs).
• When you truly need an arbitrary value, drive it with a design token by referencing the CSS custom property (w-[var(--blog-layout-fluid-width)], min-h-[var(--form-textarea-min-height)]).
• Update the allowlist sparingly—every entry should correspond to a documented token so future adjustments cascade automatically.

The lint shares the same underlying script as npm run lint:tokens, so both commands stay in lockstep with the design-system guardrails.

Theming

[data-theme] contract

The default experience renders the production dark palette. Pages and embeds can opt into alternates by setting the data-theme attribute on the <html> (or any ancestor that wraps the component). data-theme="light" promotes the light tokens defined in css/tokens.css, swapping surface, panel, border, muted, and overlay colors while keeping semantic accents consistent. Omit the attribute or set it back to default to inherit the dark baseline. Reserve additional theme keys (for example, data-theme="contrast") for upcoming accessibility palettes—the same hook will activate them once their tokens land. When scoping components inside legacy templates, prefer wrapping the smallest possible container so downstream shims continue to function.

Token overrides & experiments

Tokens are sourced from css/tokens.css and consumed as CSS custom properties. To try temporary overrides—such as custom backgrounds for a partner landing page—stack a higher-specificity selector and reassign the variable without hard-coding literal colors:

.landing[data-theme="light"] {
  --color-bg-page: var(--color-bg-surface);
  --shadow-card: 0 10px 40px rgba(12, 14, 23, 0.25);
}

Limit overrides to variables defined in css/tokens.css and document any long-lived changes in this file so the design tokens remain the source of truth. Feature-flagged experiments should wrap overrides in a data-flag-<name> selector or toggle them via controller logic so the defaults remain stable when the flag is off.

Blog layout tokens

The blog embed now consumes dedicated typography and spacing tokens alongside Tailwind utilities. css/tokens.css exposes the following helpers:

• --blog-font-size-root, --blog-font-size-display, --blog-font-size-title, --blog-font-size-body, --blog-font-size-meta, and --blog-font-size-h1-mobile scale copy across the blog shell, hero headings, and metadata.
• --blog-line-height-body and --blog-line-height-tight set the rhythm for long-form text and compact headers.
• --blog-layout-fluid-width and --blog-layout-max-width define the responsive container width; pair them with Tailwind utilities (mx-auto, md:w-[var(--blog-layout-fluid-width)], md:max-w-[var(--blog-layout-max-width)]) when mounting the blog root.
• --blog-space-compact, --blog-space-snug, --blog-space-heading-stack, --blog-space-heading-gap, --blog-space-inline-lg, --blog-space-media-stack-start, --blog-space-media-stack-end, and --blog-space-stack-xxl standardise the bespoke gaps used throughout article summaries, media blocks, and footer treatments.
• --blog-avatar-size and --blog-avatar-size-compact size topic avatars responsively.

Templates should reference these tokens (directly or via Tailwind arbitrary values) instead of hard-coded measurements so the embed stays in sync with future blog refreshes.

The blog palette now resolves from the base :root scope, making color and layout tokens theme-agnostic. Neither the light nor dark theme overrides these variables, so any future blog-specific deltas should be called out explicitly in this guide if they return.

Semantic Palette

All interactive surfaces now draw from a shared semantic color map exposed through css/tokens.css and Tailwind utility aliases. The palette is grouped into text, surface, overlay, and status slots so controllers can swap state styles without reaching for raw Tailwind hues:

• Text: text-primary, text-inverse, text-muted, text-muted-strong, and text-subtle map to --text-* tokens. Use them for copy, helper text, and frosted overlays instead of text-gray-*.
• Surfaces: bg-surface, bg-surface-alt, bg-surface-raised, bg-surface-muted, and bg-overlay-* wrap cards, modals, and scrims. Pair them with border-surface, border-overlay, or border-overlay-strong when rendering shells.
• Statuses: status-* tokens expose matching text, background, and border slots. Tailwind utilities include text-status-success, bg-status-warning-surface, border-status-danger-border, and chip helpers (.pill, .badge) that accept data-variant="info" | "success" | "warning" | "critical" | "private" | "neutral".
• Overlays: .overlay-scrim and .overlay-panel helpers consume the overlay tier tokens for modals, sheets, and popovers. Adjust the strength via data-strength/data-variant rather than applying translucent grays. Blur states now ride semantic variables—reuse --blur-modal-backdrop for scrims, --blur-modal-alert for inline notices, and --blur-thumbnail-blur for frosted imagery instead of hard-coded pixel values.

Migration guidance

• Swap raw Tailwind palette utilities (for example, text-gray-400, bg-amber-500/10, border-red-700/70) for the matching semantic utilities above. The new lint (npm run lint:tailwind-colors) fails when legacy color classes appear outside deprecated directories.
• Replace ad-hoc chips (inline-flex ... border-red-700/70 bg-red-900/40) with .pill or .badge plus a data-variant. These helpers automatically pull the correct status text/border/fill tokens.
• Use text-info/hover:text-info-strong for links that previously relied on text-blue-400 so anchors adapt in both light and dark modes.
• When rendering tinted descriptions or placeholders, prefer text-muted, text-muted-strong, or text-subtle over semi-transparent whites. Token overrides keep the same classes usable across the default and light themes.

Blog carousel markup

The short-notes carousel ships as a semantic wrapper around the blog-carousel primitive defined in css/tailwind.source.css. The runtime no longer injects inline styles or Splide classes—layout is driven entirely by data attributes that map onto tokenised CSS rules.

Structure

<section class="short-notes blog-carousel" data-carousel data-per-page="3" data-index="0">
  <div class="blog-carousel__viewport" data-carousel-viewport>
    <ul class="blog-carousel__track" data-carousel-track>
      <li class="blog-carousel__slide" data-carousel-slide data-index="0" data-active="true">
        ...
      </li>
      <!-- additional slides -->
    </ul>
    <button type="button" data-carousel-prev data-carousel-control="prev">‹</button>
    <button type="button" data-carousel-next data-carousel-control="next">›</button>
  </div>
  <div class="blog-carousel__progress blog-progress" data-carousel-progress>
    <progress class="progress progress--blog" data-progress-meter aria-label="Carousel progress"></progress>
  </div>
</section>

State contract

• data-per-page controls how many columns render inside the viewport. CSS exposes variants for 1–4 slides per page; the custom property --blog-carousel-per-page updates automatically.
• data-index represents the active page (zero-indexed). The track translates by 100% for each page, so the attribute should advance in whole-number increments rather than slide indices.
• Slides expose data-index, data-active, data-inert, and data-state. The carousel controller toggles data-state="active", "idle", and "leaving" to drive scale/opacity transitions without touching inline styles.
• The root section advertises data-state="active" | "idle" plus data-transition="auto" | "instant" when short-circuiting animations (for example, during first render or programmatic jumps).
• Progress wrappers set data-state="idle" | "active" | "paused" | "complete" while the inner <progress> leverages the shared progress primitive (data-progress-meter, data-variant="blog") so theme tokens continue to drive track/fill colours.

Controllers should rely on these data hooks when orchestrating autoplay, pausing on pointer/visibility changes, or syncing the segmented progress indicator. Avoid reintroducing inline style mutations—tests enforce the contract via the inline-style guard.

Layout & spacing extensions

The core spacing scale gained intermediate stops for tighter micro-layouts and larger hero treatments. css/tokens.css now exports --space-4xs, --space-3xs, --space-xs-snug, --space-md-plus, --space-xl-compact, --space-xl-plus, and --space-2xl-plus; Tailwind surfaces matching utilities such as p-4xs, p-3xs, px-xs-snug, py-md-plus, gap-xl-compact, px-xl-plus, and gap-2xl-plus. Pair them with the new layout primitives—--menu-min-width (min-w-menu), --modal-max-width (max-w-modal), --layout-player-max-width (max-w-player), and --layout-docs-max-width (max-w-docs)—to anchor consistent breakpoints across popovers, modals, and documentation shells without reintroducing raw rem/px literals. Blog-specific chrome reuses the same additions: the theme toggle knob now references --radius-toggle-thumb, and focus affordances draw from --outline-thick-width instead of hard-coded pixel outlines.

Previewing themes

The design-system kitchen sink (docs/kitchen-sink.html) exposes a theme switcher that mirrors the production toggle contract. Use the "Theme" select menu in the header to flip between default, light, and any preview keys (for example, contrast). This control updates document.documentElement.dataset.theme at runtime, letting you verify hover/focus/disabled states without redeploying. When authoring new palettes, add them to css/tokens.css, confirm the kitchen-sink toggle picks them up, and record before/after screenshots for review so the CI snapshots have clear context.

Focus Handling

All interactive primitives mix in the shared .focus-ring helper. It removes default outlines and applies a branded ring using focus-visible only. When building bespoke components, add .focus-ring to your root interactive element or replicate its rules:

<button class="focus-ring inline-flex items-center gap-2 ...">Label</button>

The helper includes:

• focus-visible:ring-2 with ring-info and ring-opacity-70
• focus-visible:ring-offset-2 with an offset on bg-surface
• focus-visible:transition-shadow using the tokenized duration-fast easing curve

Never hide focus styles without providing an accessible alternative.

Motion Guardrails

Motion inventory

The rg "transition" audit surfaces the components that animate by default. Keep this list in sync when new motion primitives land:

• Buttons: .btn and .btn-ghost transition their backgrounds, borders, and shadows using the shared token durations. 【F:css/tailwind.source.css†L18-L55】
• Cards and watch history: .card, .watch-history-card, and their nested controls use hover/focus transitions plus optional entry animations via data-motion="enter". 【F:css/tailwind.source.css†L238-L804】
• Popovers: .popover__panel fades and scales between [data-state] values. 【F:css/tailwind.source.css†L119-L141】
• Modals: .bv-modal__panel, .video-modal__panel, and .player-modal__content animate in concert with the modal nav/header layout helpers. 【F:docs/kitchen-sink.html†L335-L391】【F:css/tailwind.source.css†L385-L640】
• Feedback & loading: .progress-bar-fill, .status-spinner--inline, and .status-banner .status-spinner communicate state changes with width transitions or spin animations. 【F:css/tailwind.source.css†L907-L948】
• Sidebar controls: .sidebar-nav-link, .sidebar-dropup-trigger, .sidebar-collapse-toggle, and related chevrons/toggles translate, fade, and resize during rail expansion. 【F:css/tailwind.source.css†L1164-L1598】

Shadow inventory

• --shadow-popover-zap keeps the zap tip elevation consistent across themes; apply it to .popover__panel[data-variant="zap"] or related toast surfaces when you need the intense popover glow. 【F:css/tokens.css†L406-L415】【F:css/tailwind.source.css†L293-L298】
• --shadow-video-modal anchors modal playback chrome so large embeds reuse the same lift as #playerModal .video-modal__video video. 【F:css/tokens.css†L406-L415】【F:css/tailwind.source.css†L1374-L1378】
• --color-shadow-intense still exposes the raw color for bespoke drop-shadow recipes—pair it with drop-shadow-intense utilities when only the hue needs to change. 【F:css/tokens.css†L93-L101】【F:tailwind.config.cjs†L28-L32】【F:tailwind.config.cjs†L147-L157】

Reduced-motion policy

• A consolidated @media (prefers-reduced-motion: reduce) block now zeroes out transition and animation durations globally, removes motion-only transforms, and leaves opacity state changes in place so surfaces still show and hide instantly. 【F:css/tailwind.source.css†L1766-L1981】
• Motion tokens also collapse to 0s inside Tailwind's component layer so the primitives (.btn, .card, .popover__panel, watch-history tiles) inherit the same behaviour without per-selector overrides. 【F:css/tailwind.source.css†L229-L270】
• Spinners fall back to static indicators when reduced motion is requested, while focus rings remain intact because the underlying styles are unaffected—only the timing curves are reset. 【F:css/tailwind.source.css†L1778-L1981】
• When adding a new animated component, register its selector in this block (or reuse the tokenised durations) so reduced-motion users never see unintended transitions. Document the addition here alongside the inventory.

Component Primitives

Buttons

Class	Description
.btn	Primary action button (bg-primary, white text). Hover lifts to bg-info-strong, focus pushes to bg-info-pressed, disabled reduces opacity.
.btn-ghost	Framed secondary action. Transparent by default with subtle border, fills with bg-panel-hover on hover/focus.

Both buttons:

• Use .focus-ring internally
• Include pointer-blocking and opacity changes on :disabled
• Are uppercase with wide tracking to match our existing CTA styling

Mix in Tailwind utilities for icon spacing (gap-3), sizing (px-lg, py-sm), or layout (w-full). Avoid overriding colors unless introducing a new semantic variant.

Variants & Toggle States

• Apply data-variant="critical" to .btn-ghost when rendering destructive affordances (for example, "Remove variant" pills inside repeater rows). The primitive swaps the border and text colors to the critical palette and deepens the fill on hover/focus.
• Toggle groups can rely on [aria-pressed="true"] or data-state="active" without extra utilities. When a .btn-ghost reports an active state it automatically promotes to the filled primary style.

<div class="inline-flex items-center rounded-full bg-panel/80 p-1" role="group">
  <button class="btn-ghost flex-1" type="button" aria-pressed="true">Custom</button>
  <button class="btn-ghost flex-1" type="button" aria-pressed="false">Cloudflare</button>
</div>

Badges

.badge renders an inline pill (bg-panel, uppercase text). Opt into semantic variants with data-variant="info", data-variant="critical", or data-variant="neutral". Layer on utilities for icon alignment or truncation.

Cards

.card is the base surface for grid items and panels:

• Rounded corners (rounded-lg) and bg-card
• Token shadows on hover
• Focus states reuse .focus-ring
• Accepts data-state="private" | "critical" | "disabled" for special treatments

Combine with padding utilities per layout. Interactive cards should maintain cursor-pointer manually (see legacy shim example below) until templates adopt dedicated controller classes.

2025-10-11 update: The legacy .video-card* shim selectors were removed. Video grids should now render plain .card elements and opt into semantic variants via data-state, data-alert, and data-motion attributes. Runtime code no longer maps the deprecated classes, so older selectors will not receive token updates.

Form Inputs

.form-control is the base primitive for text entry surfaces. It handles layout (block, w-full), rounded corners, subtle borders, muted placeholders, and the shared focus ring. Hovering deepens the border, focus highlights with border-info-strong, :invalid raises a critical border, and :disabled mutes the field while blocking pointer events.

Specialisations reuse .form-control:

• .input – Standard single-line text input.
• .textarea – Multi-line input with a minimum height (min-h-[var(--form-textarea-min-height)]) and resize-y enabled.
• .select – Native <select> element with appearance-none, an integrated arrow glyph, and consistent spacing (pr-10).

All three share hover, focus-visible, disabled, and invalid treatments. Layer on utilities (h-12, text-lg, icon padding) as needed without re-declaring tokens.

Controllers can mark read-only fields by setting data-state="locked" alongside the existing readonly attribute. The attribute shifts the background to bg-overlay-panel-soft, deepens the border (border-border-sidebar-strong), and suppresses the focus ring so locked inputs stay visually distinct without falling back to !important overrides. The same hook works on .input, .textarea, .select, and any raw .form-control element—disabled states keep the locked palette.

Arrow and checkbox adornments now lean entirely on tokens: --form-select-icon-offset, --form-select-icon-gap, --form-select-icon-hit-area, and --form-select-icon-size position the native select chevron, while --form-checkbox-checkmark-offset keeps the checkmark aligned at any scale. Textareas pull their baseline from --form-textarea-min-height, and thin scrollbars reuse the shared --scrollbar-thin-width so embedded panels feel consistent across browsers.

<form class="bv-stack bv-stack--tight" aria-labelledby="zapAmountLabel">
  <label
    id="zapAmountLabel"
    class="text-xs font-semibold uppercase tracking-wide text-muted-strong"
  >
    Zap amount (sats)
  </label>
  <input
    id="zapAmountInput"
    type="number"
    min="1"
    step="1"
    class="input"
    placeholder="Enter sats"
  />
  <button class="btn" type="submit">Send</button>
</form>

For toggles:

• .checkbox resets native appearance, applies the token border/background, and swaps to the info palette when checked. The checkmark is rendered via ::after, and disabled states lower contrast while keeping the focus ring behaviour.
• .switch renders a pill track with a translating thumb (::before). Apply [aria-checked="true"] or .is-on to move the thumb and recolor the track. Motion respects prefers-reduced-motion while maintaining the focus ring.

Modal Surface

• .bv-modal anchors fixed overlays (full-viewport flexbox centered layout).
• .bv-modal-backdrop applies the tokenized overlay color with blur.
• .bv-modal__panel hosts modal content (bg-surface, shadow-modal, focus ring).

Sizing now comes from dedicated tokens: max-w-modal and rounded-modal-xl map to --modal-max-width and --radius-modal-xl, while icon controls reuse --icon-size-lg, --icon-size-md, and --icon-button-ring-width for consistent hit targets. Progress indicators pick up --modal-progress-height, and the player modal inherits max-w-player so hero metadata never exceeds --layout-player-max-width.

Use --modal-sheet-inline-max when you need a sheet to breathe on narrow viewports without exceeding the standard modal width. The token resolves to the smaller of 90vw and --modal-max-width, so base sheet templates hug the viewport while large-screen overrides (for example, lg:max-w-4xl) can still opt into broader layouts. Reach for --modal-max-width directly when the panel should stay anchored to the canonical modal width across breakpoints.

Compose them together when mounting new modal portals. If you need a drawer or sheet, start from these primitives and adjust spacing/positioning via utilities.

Modal Actions

Action rows in login, disclaimer, and upload flows now pair .btn-ghost and .btn directly. Layer layout utilities such as w-full or gap-3 without re-adding custom focus rings.

<footer class="modal-footer flex gap-3">
  <button class="btn-ghost flex-1" type="button">Cancel</button>
  <button class="btn flex-1" type="submit">Publish</button>
</footer>

Static modal partials (login, application, feedback, etc.) should call the helpers exported from js/ui/components/staticModalAccessibility.js—prepareStaticModal, openStaticModal, and closeStaticModal—to attach focus trapping, Escape/backdrop dismissal, and the shared data-open/html.modal-open toggles without duplicating controller logic.

Headers

.ds-header replaces the legacy header { … } reset. Apply it to page chrome that should inherit the shared rhythm: flex alignment (items-center, justify-start) and tokenized vertical padding (py-md). Layer layout utilities per surface—for example, justify-between on the kitchen-sink demo or mb-8 on the app shell.

Pair .ds-header__logo with <img> or inline logo wrappers to standardize sizing (h-24, w-auto, max-w-none) without reintroducing element selectors. Compose additional utilities (h-16, responsive overrides) when a view needs alternate scale.

Logo glyphs now rely on dedicated selectors inside the SVG: apply .bv-logo__accent to the nine-block mark, .bv-logo__wordmark to the lettering, and .bv-logo__background to any surrounding tile. These hooks read from the CSS custom properties that .bv-logo seeds, so themes can flip palettes purely through attributes (data-variant, data-wordmark, etc.) without reintroducing inline fill or color overrides.

Popovers

Use .popover as the relative anchor for floating content. Nest .popover__panel for the floating surface—it’s positioned with the shared helper, inherits the shared focus ring, and animates with opacity/scale tokens. Toggle [data-state="open"] on the panel to switch between the collapsed (opacity-0 scale-95) and expanded (opacity-100 scale-100) states.

<div class="popover">
  <button class="btn" type="button">Open filters</button>
  <div class="popover__panel" role="dialog" data-state="open">
    <p class="text-sm text-muted">Fine-tune the current feed using tags and duration filters.</p>
  </div>
</div>

Use the shared positioning helper (js/ui/utils/positionFloatingPanel.js) instead of manual utility offsets. It calculates placement, flips when the surface collides with the viewport, and clamps to an optional padding gutter—all while listening for scroll/resize events and using ResizeObserver when available. Call it with the trigger and panel elements, then invoke positioner.update() once the panel is visible:

import positionFloatingPanel from "../utils/positionFloatingPanel.js";

const positioner = positionFloatingPanel(triggerEl, panelEl, {
  placement: "bottom", // top | bottom | left | right
  alignment: "end",    // start | center | end (RTL aware)
  offset: 8,
  viewportPadding: 16,
});

panelEl.hidden = false;
panelEl.dataset.state = "open";
positioner.update();

The helper tags the trigger and surface with floating metadata so CSS tokens can express transform-origins and fallback coordina tes without bespoke inline styles. Panels receive data-floating-panel="true" plus placement, alignment, strategy, and directio n hooks (data-floating-placement, data-floating-alignment, data-floating-strategy, data-floating-dir). The script updates CSS custom properties --floating-fallback-top/--floating-fallback-left on each measurement so css/tailwind.source.css can control layout purely through tokens. Browsers that support CSS anchor positioning flip data-floating-mode to anchor, but th e same fallback properties keep older engines aligned. 【F:js/ui/utils/positionFloatingPanel.js†L238-L251】【F:css/tailwind.sourc e.css†L163-L236】

Recommended container pattern:

• Wrap the trigger and panel in .popover so the markup stays discoverable and inherits spacing tokens.
• Leave the wrapper’s overflow visible; the helper defaults to position: fixed, so floating surfaces escape scroll containers without getting clipped. Opt into { strategy: "absolute" } if you intentionally want the panel constrained.
• When tearing down a component, call positioner.destroy() to drop scroll/resize listeners.

The motion helpers defer to the global motion tokens so Task 5 can adjust timing globally without revisiting individual components. Animations respect prefers-reduced-motion by collapsing to opacity-only transitions.

Sidebar shell & controls

The navigation rail pulls its rhythm from dedicated sidebar tokens in css/tokens.css. The shell, panels, and footer reuse shared spacing primitives (--space-sidebar-shell-inline, --space-sidebar-shell-block-start, --space-sidebar-shell-block-end, --space-sidebar-panel-gap, --space-sidebar-panel-padding-block, --space-sidebar-panel-padding-inline, --space-sidebar-footer-gap) alongside component-specific radii and shadows (--radius-sidebar-shell, --radius-sidebar-panel, --radius-sidebar-nav, --shadow-sidebar-shell, --shadow-sidebar-accent, --shadow-sidebar-trigger, --shadow-sidebar-dropup, --shadow-sidebar-panel, --shadow-sidebar-focus-ring). These values also size fallback classes like .sidebar-nav-link, .sidebar-dropup-trigger, and .sidebar-dropup-panel so legacy templates stay legible. 【F:css/tokens.css†L94-L138】【F:css/tailwind.source.css†L1829-L2182】

Frosted glass treatments share a blur stack as well. Reference --sidebar-backdrop-blur across the shell, nav links, and footer triggers, then pull the matching saturation tokens (--sidebar-shell-backdrop-saturation, --sidebar-nav-backdrop-saturation, --sidebar-trigger-backdrop-saturation, --sidebar-panel-backdrop-saturation) or --sidebar-panel-backdrop-blur for popovers instead of reintroducing literal blur()/saturate() values. 【F:css/tokens.css†L70-L118】【F:css/tailwind.source.css†L2059-L2402】

Tailwind now exposes matching utilities for layouts that opt into the design system directly: use px-sidebar-shell-inline, pt-sidebar-shell-block-start, pb-sidebar-shell-block-end, gap-sidebar-panel-gap, and rounded-sidebar-shell/rounded-sidebar-nav for structure, then shadow-sidebar-shell, shadow-sidebar-accent, or shadow-sidebar-dropup to match the bespoke glow states. Combine them with existing color utilities to compose new sidebar sections without reintroducing raw measurements. 【F:tailwind.config.cjs†L115-L155】

Iconography and motion helpers rely on fresh tokens as well: --icon-size-sm, --icon-size-md, and --icon-size-lg standardise glyph sizing across nav links, collapse toggles, and dropup triggers, while --space-sidebar-nav-translate powers the translate offsets used when collapsing the rail. Thin overlays inherit --scrollbar-thin-width so modal and sidebar scroll containers feel identical.

Menus

.menu normalises list-based command menus with consistent padding. Pair it with .menu__heading for optional section labels, .menu__separator for dividers, and .menu__item for actionable rows. Each item supports hover, active (data-state="active"), and critical (data-variant="critical") palettes plus disabled fallbacks through either disabled or aria-disabled="true".

<div class="popover">
  <button class="btn-ghost" type="button">Command palette</button>
  <div class="popover__panel" role="menu" data-state="open">
    <div class="menu" role="none">
      <p class="menu__heading" role="presentation">Navigation</p>
      <button class="menu__item" role="menuitem">Search videos</button>
      <button class="menu__item" role="menuitem" data-state="active">Go live dashboard</button>
      <div class="menu__separator" role="separator"></div>
      <button class="menu__item" role="menuitem" data-variant="critical">Delete current draft</button>
      <button class="menu__item" role="menuitem" disabled>Switch profile (pro only)</button>
    </div>
  </div>
</div>

The helpers rely on layout utilities (flex, gap-*) so you can safely inject icons, shortcuts, or nested badges without restyling the base tokens.

Zap Popover

Compose .popover with a zap-specific panel variant when you need to surface the tipping form inline. Toggle data-state="open" on the .popover__panel and remove its hidden attribute when the dialog is visible. The data-variant="zap" hook reuses the frosted-glass styling defined in css/tailwind.source.css.

<div class="popover">
  <button class="btn-ghost h-10 w-10 rounded-full p-0" type="button" aria-haspopup="dialog" aria-expanded="false">
    <img src="assets/svg/lightning-bolt.svg" alt="Zap" class="h-5 w-5" />
  </button>
  <div
    class="popover__panel card w-72 max-w-popover-safe space-y-4"
    role="dialog"
    aria-hidden="true"
    data-variant="zap"
    data-state="closed"
    hidden
  >
    <div class="flex items-center justify-between gap-4">
      <h3 class="text-xs font-semibold uppercase tracking-wide text-muted">Send a zap</h3>
      <button class="btn-ghost h-8 w-8 rounded-full p-0" type="button" aria-label="Close zap dialog">✕</button>
    </div>
    <form class="space-y-4">
      <label class="block text-xs font-semibold uppercase tracking-wide text-muted" for="zapAmountExample">
        Zap amount (sats)
      </label>
      <input id="zapAmountExample" class="input" type="number" min="1" step="1" inputmode="numeric" />
      <button class="btn w-full" type="submit">Send</button>
    </form>
  </div>
</div>

Grid Stack

.grid-stack offers gap tokens for dense layouts. Add data-variant="cards" for responsive card grids (grid-cols-1 → sm:grid-cols-2 → xl:grid-cols-3). Switch to data-orientation="vertical" for stacked flex columns that reuse the same spacing tokens.

Layout Helpers

• .bv-stack creates a vertical flex stack with the default large gap (var(--space-lg)). Use it for page sections such as the watch-history summary blocks.
• .bv-stack--tight reduces the gap to var(--space-md) while inheriting the .bv-stack flex behaviour. Combine the modifier when stacking smaller card fragments or form controls inside profile templates.
• .bv-grid-video centralises the responsive video grid (repeat(auto-fill, minmax(20rem, 1fr))) with the standard gutter (gap-xl) and vertical padding (py-lg). Apply it to feed, subscriptions, and channel views instead of repeating inline grid rules.

Legacy Compatibility Shims

During migration we keep existing selectors alive by layering @apply calls in css/tailwind.source.css. Notable shims:

• #profileModal .profile-switcher* → .card, .badge, .btn-ghost

2025-10-11: The .video-card shim family was removed. Templates must emit .card elements with the appropriate data-state and data-alert attributes instead of relying on the legacy class names.

We continue to expose aliases such as .profile-switcher and nested variations (for example, .profile-switcher__item) so existing profile and admin controllers stay functional while downstream templates finish their migration. These shims live under the "Legacy component compatibility" section and will be removed once templates switch to the new primitives.

Modal primitives: Always mount .bv-modal, .bv-modal-backdrop, and .bv-modal__panel together. Controllers expect this trio, so there is no compatibility layer for alternate selectors.

Shim removal checklist (Task DS-742):

• Confirm no production templates emit .profile-switcher* selectors (owners: @ui-templates, @design-systems).
• Verify the torrent beacon renders .card, .btn, .btn-ghost, and .input primitives with no fallback selectors (owner: @torrent-beacon).
• Verify staging renders with data-ds="new" across surfaces and run kitchen-sink visual snapshots to ensure no regressions.
• Delete residual @apply rules under "Legacy component compatibility" in css/tailwind.source.css.
• Announce the removal in release notes and update downstream embed documentation.

Owners: Design Systems Guild (@design-systems) with support from the Templates crew (@ui-templates) and the torrent beacon maintainers (@torrent-beacon).

Target removal release: 2025.04 mainline (aligns with the shim removal milestone tracked in DS-742). Audit usage after the Q1 2025 UI refresh and delete remaining shims no later than the April 2025 deployment window. At that point the compatibility layer will be removed once dependent feature flags confirm that no legacy selectors remain in production HTML.

Selector migration table

Legacy selector	Replacement primitive(s)	Beacon / app notes	Feature-flag strategy
.video-card, .video-card__meta, .video-card--loading	.card with data-state + utility classes	Removed in web app; ensure beacon dashboards render .card with skeleton states instead of .video-card--loading.	Deploy directly and validate in staging before rolling to beacon.
.profile-switcher, .profile-switcher__item	.card rows + .btn-ghost toggles	Keep shim until profile modal Reactors deploy; beacon does not consume this selector.	Roll out once QA signs off; no flag gating remains.
.button, .button-danger (Skeleton)	.btn, .btn-ghost[data-variant="critical"]	Critical for torrent beacon—replace the Angular templates before removing Skeleton CDN.	Coordinate a staged deploy; the design system is always on so fallbacks must ship in a separate release if required.
.u-full-width, .input-text	.input, .select, .form-control	Applies to upload forms and beacon filter controls; also update tests that target legacy classes.	Update markup globally; controllers now always run in the design system mode.
.modal-container, .modal-content	.bv-modal, .bv-modal-backdrop, .bv-modal__panel	Retired selectors—emit the primitives exactly so accessibility, animation, and controller hooks stay wired.	N/A — unified primitives only.

Migration Notes (Q4 2024)

• Modal templates across the app now mount .bv-modal, .bv-modal-backdrop, and .bv-modal__panel primitives directly. Controllers such as ProfileModalController and the upload modal orchestrator were updated to expect these primitives, so any new modal should follow the same structure for consistent accessibility and animation hooks.
• The compatibility shim keeps the .profile-switcher selector family alive temporarily so third-party embeds and cached HTML fragments continue to render while operators redeploy updated templates. Keep the aliases until the April 2025 removal window above, then delete the shim and update any last callers to the new .card/.btn-ghost structure.

Overlay layering scale

Overlay stacks now use semantic z-index tokens. Reach for these utilities instead of raw numeric values so floating surfaces remain predictable across the app:

Token	Utility class	Primary usage
--z-overlay-nav	z-overlay-nav	Mobile navigation toggles, sticky modal nav bars
--z-overlay-floating	z-overlay-floating	Popovers, floating status overlays, async progress shells
--z-overlay-toast	z-overlay-toast	Toast managers and transient notifications
--z-modal-root / --z-modal-overlay / --z-modal-content	z-[var(--z-modal-root)] primitives	Modal scaffolding (.bv-modal, .bv-modal-backdrop, .bv-modal__panel)

Backdrops share a common helper: .ds-overlay-backdrop applies the fixed positioning, tone, and blur defined by --overlay-backdrop-color / --overlay-backdrop-blur. Pair it with the appropriate z-overlay-* utility when you need to tune stacking above or below other surfaces.

Beacon client migration

The torrent beacon now shares the Tailwind bundle used across bitvid. The standalone torrent/beacon.html drops Skeleton/FoA CDNs in favour of css/tailwind.generated.css, adopts the .card, .btn, .btn-ghost, and .input primitives, and relies on .bv-stack for spacing inside Angular partials. Inline SVG icons replace FontAwesome so controls stay lightweight while inheriting tokenised focus and hover states.

Angular templates under torrent/views/ should follow the refreshed structure:

• Wrap primary sections in .card and layer Tailwind utilities for layout (grid, gap-xl, overflow-auto).
• Use .input, .select, .btn, and .btn-ghost (with data-variant="critical" for destructive actions) instead of legacy .u-full-width, .button, or .button-danger classes.
• Prefer token-backed utilities for spacing and typography (px-6, py-6, text-muted) over ad-hoc CSS.
• Reuse the fixed overlay spinner pattern (ds-overlay-backdrop z-overlay-floating plus an animate-spin text-info-strong SVG) for async states so overlays stay consistent with the new palette.

When adding new torrent affordances, mirror the existing markup: inline 24×24 SVG strokes at 2px, .focus-ring on interactive anchors, and .bv-stack for vertical rhythm. This keeps the beacon aligned with the design system without reintroducing the deprecated Skeleton grid.

When to Mix Utilities

Use the primitives for foundation and lean on Tailwind utilities for:

• Layout (flex, grid, gap-*, justify-*)
• Sizing (w-*, h-*, min-w-*)
• Typography tweaks (text-left, font-light)
• State variations not yet encoded as tokens (e.g., success/neutral buttons)

Avoid re-declaring token values manually. If a new pattern repeats, promote it into a primitive or request new tokens to keep styling consistent.

Visual snapshot review workflow

Continuous integration captures Playwright-powered screenshots of docs/kitchen-sink.html (tests/visual/kitchen-sink.spec.ts) on every pull request. When a snapshot job fails:

1. Read the diff produced by Playwright (attached as an artifact) and compare it with your local preview. The harness highlights per-pixel changes so reviewers can distinguish deliberate theme updates from regressions.
2. Reproduce locally with npm run test:visual -- --update-snapshots to refresh the expected images after verifying the change in the kitchen sink.
3. Document the intent in the PR description (include before/after screenshots or reference the kitchen-sink toggle state) so reviewers and QA know the snapshot change is expected.

The design system doc is the single source of truth for reviewing these failures—if a diff contradicts the guidance above, treat it as a regression, request updates, and block the merge until the visual snapshot stabilises.