Stacks Design Taste

Stacks Design Taste: Anti-Slop Frontend Skill

Related skills: stacks-stx (templating, directives, signals, SSR/hydration), stacks-composables (full composable reference), stacks-crosswind (utilities, dark mode, theming), stacks-ui (Craft native + headless components, Transition). Companions: stacks-design-soft, stacks-design-minimalist, stacks-design-brutalist, stacks-redesign, stacks-design-output.

Landing pages, portfolios, and redesigns in Stacks. Not dashboards, not data tables, not multi-step product UI (see Section 13). Every rule below is contextual. None of it fires automatically. First read the brief, then pull only what fits. Everything is built with stx templates + Crosswind utilities + stx composables. No JSX, no external motion library.

0. BRIEF INFERENCE (Read the Room Before Anything Else)

Before touching code or tweaking dials, infer what the user actually wants. Most LLM design output is bad because the model jumps to a default aesthetic instead of reading the room.

0.A Read these signals first

1. Page kind - landing (SaaS / consumer / agency / event), portfolio (dev / designer / creative studio), redesign (preserve vs overhaul), editorial / blog.
2. Vibe words the user used - "minimalist", "calm", "Linear-style", "Awwwards", "brutalist", "premium consumer", "Apple-y", "playful", "serious B2B", "editorial", "agency-y", "glassy", "dark tech".
3. Reference signals - URLs they linked, screenshots they pasted, products they named, brands they're competing with.
4. Audience - B2B procurement panel vs. design-conscious consumer vs. recruiter scanning a portfolio. The audience picks the aesthetic, not your taste.
5. Brand assets that already exist - logo, color, type, photography. For redesigns, these are starting material, not optional input (see Section 11).
6. Quiet constraints - accessibility-first audiences, public-sector, regulated industries, trust-first commerce, kids' products. These constraints OVERRIDE aesthetic preference.

0.B Output a one-line "Design Read" before generating

Before any code, state in one line: "Reading this as: <page kind> for <audience>, with a <vibe> language, leaning toward <aesthetic family> built on the Stacks stack."

Example reads:

• "Reading this as: B2B SaaS landing for technical buyers, with a Linear-style minimalist language, leaning toward Crosswind utilities + Geist + restrained CSS motion."
• "Reading this as: solo designer portfolio for hiring managers, with an editorial / kinetic-type language, leaning toward Crosswind + scroll-driven CSS animation + custom typography."
• "Reading this as: redesign of a trust-first service site, leaning toward high-contrast neutral system, accessibility-first, minimal motion."

0.C If the brief is ambiguous, ask one question, do not guess

Ask exactly one clarifying question - never a multi-question dump - and only when the design read genuinely diverges. Example: "Should this feel closer to Linear-clean or Awwwards-experimental?"

If you can confidently infer from context, do not ask. Just declare the design read and proceed.

0.D Anti-Default Discipline

Do not default to: AI-purple gradients, centered hero over dark mesh, three equal feature cards, generic glassmorphism on everything, infinite-loop micro-animations everywhere, Inter + slate-900. These are the LLM defaults. Reach past them deliberately based on the design read.

1. THE THREE DIALS (Core Configuration)

After the design read, set three dials. Every layout, motion, and density decision below is gated by these.

• DESIGN_VARIANCE: 8 - 1 = Perfect Symmetry, 10 = Artsy Chaos
• MOTION_INTENSITY: 6 - 1 = Static, 10 = Cinematic / Physics
• VISUAL_DENSITY: 4 - 1 = Art Gallery / Airy, 10 = Cockpit / Packed Data

Baseline: 8 / 6 / 4. Use these unless the design read overrides them. Do not ask the user to edit this file - overrides happen conversationally.

1.A Dial Inference (design read -> dial values)

1.B Use-Case Presets

1.C How the Dials Drive Output

Use these (or user-overridden values) as global variables. Cross-references throughout this document refer to these exact variable names - never invent aliases like LAYOUT_VARIANCE or ANIM_LEVEL.

2. BRIEF -> FOUNDATION MAP

Once you have the design read (Section 0) and dials (Section 1), pick the right foundation. Do not invent CSS for things Stacks already ships. Do not pretend an aesthetic trend is an official system.

2.A The Stacks foundation (default for every Stacks app)

The React skill's "reach for Fluent / Carbon / Material / shadcn" advice does not apply in a Stacks app. Your foundation is always:

Honesty rule (retargeted): use the real official thing, do not hand-recreate tokens. In Stacks, the real official thing is Stacks UI + Crosswind + Iconify. Do NOT tell the user to npm install Fluent, Carbon, Material, Radix, or shadcn into a Stacks app. Do NOT hand-recreate a component that already exists in Stacks UI.

One system per project = the Stacks stack. External design systems are out of scope unless the user explicitly runs a separate non-Stacks frontend.

2.B When the brief is an aesthetic, not a system

Aesthetic directions have no package. Build them with native CSS + Crosswind. Be honest in code comments about what is borrowed inspiration vs. real material.

3. DEFAULT ARCHITECTURE & CONVENTIONS

Unless the design read pulls in an aesthetic-specific companion, these are the defaults.

3.A Stack

• Templating: stx SFC files (.stx) with three optional blocks: <script>, <template> (or bare markup), <style>. Pages/views in resources/views/*.stx, components in resources/components/*.stx, layouts in resources/layouts/*.stx.
  • SERVER vs CLIENT split (the stx equivalent of RSC): put data fetching, DB access, and secrets in <script server> (stripped from the client bundle). Put browser-only behavior (motion, pointer, scroll observers) in <script client>. A plain <script> runs on both. There is no 'use client' directive - the block type IS the boundary.
  • INTERACTIVITY ISOLATION: any component that observes scroll, tracks the pointer, or runs CSS-driven motion keeps its interactive logic in a <script client> block. Server rendering stays static.
• Styling: Crosswind (Tailwind-compatible utilities). Scoped rules go in the .stx <style> block; tokens go in CSS custom properties. See stacks-crosswind.
• Motion: CSS + composables ONLY. Stacks ships no animation library (Section 5). Never import motion/react, framer-motion, or gsap.
• Fonts: Stacks fonts config plus <link rel="preconnect"> + stylesheet (or self-hosted @font-face) in the layout .stx <head>, always font-display: swap. There is no next/font. See Section 4.1.

HARD BANS inside every stx <script> block: never var, never document.*, never window.*. Use signals, composables, and directives instead (this is a CLAUDE.md rule, not a preference).

3.B State & Reactivity

• Local reactive state uses signals: state(initial) (read count(), write count.set(v) / count.update(n => n + 1)), derived(() => ...) for computed, effect(() => ...) for side effects. Element refs use useRef('name').
• Translation from React if you are porting: useState -> state, useMemo -> derived, useEffect -> effect, useRef -> useRef.
• NEVER drive continuous values (mouse position, scroll progress, pointer physics, magnetic hover) through a signal you re-read every frame. Writing signal state on every pointer or scroll frame re-runs reactive effects and collapses on mobile. Instead drive a CSS custom property from inside an effect (Section 5.D) or let CSS scroll-driven animations do the work with no script at all.

3.C Icons

• Use Iconify utility classes. stx ships 200K+ Iconify icons as classes: <i class="i-hugeicons-{name}"></i>, or any collection i-{collection}-{name} (i-ph-arrow-right, i-tabler-check). Size and color with Crosswind: class="i-hugeicons-book-open h-6 w-6 text-gray-500".
• Default collection: hugeicons. Keep one collection per project. Standardize stroke weight.
• NEVER hand-roll SVG icon paths. NEVER npm install lucide-react / @phosphor-icons/* / any icon package. The Iconify classes replace all of that. If a glyph is missing, pull it from another Iconify collection - do not draw paths from scratch.

3.D Emoji Policy

Discouraged by default in code, markup, and visible text. Replace symbols with Iconify glyphs. Override: allow emojis only when the user explicitly asks for a playful / chat-style / social-native vibe, and even then use them sparingly with intent.

3.E Responsiveness & Layout Mechanics

• Standardize breakpoints (sm 640, md 768, lg 1024, xl 1280, 2xl 1536).
• Contain page layouts using max-w-[1400px] mx-auto or max-w-7xl.
• Viewport Stability: NEVER use h-screen for full-height hero sections. ALWAYS use min-h-[100dvh] to prevent layout jumping on mobile (iOS Safari address bar).
• Grid over Flex-Math: NEVER use complex flexbox percentage math (w-[calc(33%-1rem)]). ALWAYS use CSS Grid (grid grid-cols-1 md:grid-cols-3 gap-6).

3.F Dependency Verification (mandatory)

Before importing ANY 3rd-party library, check package.json. Most of what you need is already in the Stacks stack (Stacks UI, Crosswind, Iconify, composables) and needs no install. If you genuinely need a missing package, output the install command first. Never assume a library exists.

4. DESIGN ENGINEERING DIRECTIVES (Bias Correction)

LLMs default to cliches. Override these defaults proactively. Each rule has a context-aware override path.

4.1 Typography

• Display / Headlines: Default text-4xl md:text-6xl tracking-tighter leading-none.

• Body / Paragraphs: Default text-base text-gray-600 leading-relaxed max-w-[65ch].

• Loading mechanism (Stacks): declare font metadata in the Stacks fonts config, then load in the layout .stx <head> with <link rel="preconnect"> + stylesheet, or self-host with @font-face. Always font-display: swap. There is no next/font. Never block render on a webfont.

• Sans font choice:

  • Discouraged as default: Inter. Pick Geist, Outfit, Cabinet Grotesk, Satoshi, or a brand-appropriate serif first.
  • Override: Inter is acceptable when the user explicitly asks for a neutral / standard / Linear-style feel, or when the brief is a public-sector / accessibility-first site.

• Pairings to know: Geist + Geist Mono, Satoshi + JetBrains Mono, Cabinet Grotesk + Inter Tight, GT America + IBM Plex Mono.

• SERIF DISCIPLINE (VERY DISCOURAGED AS DEFAULT):

  • Serif is very discouraged as the default font for any project. "It feels creative / premium / editorial" is NOT a reason to reach for serif. The agent's default mental model that "creative brief = serif" is the single most-tested AI tell in production rounds.
  • Serif is only acceptable when ONE of these is explicitly true:
    • The brand brief literally names a serif font, OR
    • The aesthetic family is genuinely editorial / luxury / publication / manuscript / heritage / vintage AND you can articulate why this specific serif fits this specific brand
  • For everything else (creative agency, design studio, modern brand, premium consumer, portfolio, lifestyle), default sans-serif display (Geist Display, ABC Diatype, Sohne Breit, Cabinet Grotesk Display, Migra Sans, GT Walsheim, Inter Display, PP Neue Montreal). Sans display fonts are not "boring", they are the default for the same reason black is the default in fashion.
  • EMPHASIS RULE (related): When you want to emphasize a word within a headline, use italic or bold of the SAME font. Do NOT inject a random serif word into a sans headline (or vice versa) just to add visual interest. Mixed-family emphasis is amateur. Italic/bold emphasis in the same family is the right move.
  • Specifically BANNED as defaults: Fraunces and Instrument_Serif (the two LLM-favorite display serifs).
  • If a serif is justified (rare, per the above), rotate from this pool, do NOT reuse the same serif across consecutive projects: PP Editorial New, GT Sectra Display, Cardinal Grotesque, Reckless Neue, Tiempos Headline, Recoleta, Cormorant Garamond, Playfair Display, EB Garamond, IvyPresto, Migra, Editorial Old, Saol Display, Domaine Display, Canela, Schnyder, Tobias, NB Architekt, ITC Galliard.

• ITALIC DESCENDER CLEARANCE (mandatory): When italic is used in display type and the word contains a descender letter (y g j p q), leading-[1] or leading-none will clip the descender. Use leading-[1.1] minimum and add pb-1 or mb-1 reserve on the wrapping element. Audit every italic word in display headlines before shipping.

4.2 Color Calibration

• Max 1 accent color. Saturation < 80% by default.

• THE LILA RULE: The "AI Purple / Blue glow" aesthetic is discouraged as a default. No automatic purple button glows, no random neon gradients. Use neutral bases (Zinc / Slate / Stone) with high-contrast singular accents (Emerald, Electric Blue, Deep Rose, Burnt Orange, etc.).

• Override: if the brand or brief explicitly asks for purple / violet / lila, embrace it. But execute with intent: consistent palette, harmonised neutrals, restrained gradients. Not generic AI gradient slop.

• One palette per project. Do not fluctuate between warm and cool grays within the same project.

• COLOR CONSISTENCY LOCK (mandatory): Once an accent color is chosen for a page, it is used on the WHOLE page. A warm-grey site does not suddenly get a blue CTA in section 7. A rose-accented site does not get a teal status badge in the footer. Pick one accent, lock it, audit every component before shipping.

• PREMIUM-CONSUMER PALETTE BAN (mandatory, second-most-recurring AI-tell):

  • For premium-consumer briefs (cookware, wellness, artisan, luxury, heritage craft, DTC home goods, etc.) the LLM default is warm beige/cream + brass/clay/oxblood/ochre + espresso/ink dark text. Concretely banned hex families as default backgrounds and accents:
    • Backgrounds: #f5f1ea, #f7f5f1, #fbf8f1, #efeae0, #ece6db, #faf7f1, #e8dfcb (all "warm paper / cream / chalk / bone")
    • Accents: #b08947, #b6553a, #9a2436, #9c6e2a, #bc7c3a, #7d5621 (all "brass / clay / oxblood / ochre")
    • Text: #1a1714, #1a1814, #1b1814 (all "espresso / warm near-black")
  • This palette is BANNED as the default reach for premium-consumer briefs. Every premium-consumer site you have ever shipped uses this exact palette. The brand becomes invisible.
  • Default alternatives (rotate, do not reuse):
    • Cold Luxury: silver-grey + chrome + smoke
    • Forest: deep green + bone + amber accent
    • Black and Tan: true off-black + warm tan, sharp contrast, no beige
    • Cobalt + Cream: saturated blue against a single neutral, no brass
    • Terracotta + Slate: warm rust against cool grey, no brass
    • Olive + Brick + Paper: muted olive plus brick-red accent
    • Pure monochrome + single saturated pop: off-white + off-black + one bright accent (electric blue, emerald, hot pink, etc.)
  • Palette-rotation rule: if the previous premium-consumer project you generated used the beige+brass family, this one MUST use a different family. Do not ship the same warm-craft palette twice in a row.
  • Override: the beige+brass+espresso palette is acceptable ONLY when the brand brief explicitly names those colors, or when the brand identity is genuinely vintage / artisan / warm-craft AND you can articulate why this specific palette fits this specific brand. Default-reaching for it because "this is a cookware brief" is banned.

4.3 Layout Diversification

• ANTI-CENTER BIAS: Centered hero / H1 sections are avoided when DESIGN_VARIANCE > 4. Force "Split Screen" (50/50), "Left-aligned content / right-aligned asset", "Asymmetric white-space", or scroll-pinned structures.
• Override: centered hero is OK for editorial / manifesto / launch-announcement briefs where the message itself is the design.

4.4 Materiality, Shadows, Cards

• Use cards ONLY when elevation communicates real hierarchy. Otherwise group with border-t, divide-y, or negative space.
• When a shadow is used, tint it to the background hue. No pure-black drop shadows on light backgrounds.
• For VISUAL_DENSITY > 7: generic card containers are banned. Data metrics breathe in plain layout.
• SHAPE CONSISTENCY LOCK (mandatory): Pick ONE corner-radius scale for the page and stick to it. Options: all-sharp (radius 0), all-soft (radius 12-16px), all-pill (full radius for interactive). Mixed systems are allowed only when there is a documented rule (e.g. "buttons are full-pill, cards are 16px, inputs are 8px") and that rule is followed everywhere. Round buttons in a square layout, or square cards on a pill-button page, is broken design.

4.5 Interactive UI States

LLMs default to "static successful state only." Always implement full cycles:

• Loading: Skeletal loaders matching the final layout's shape. Avoid generic circular spinners.
• Empty States: Beautifully composed; indicate how to populate.
• Error States: Clear, inline (forms), or contextual (use Stacks UI Transition for toasts, transient only).
• Tactile Feedback: On :active, use active:-translate-y-[1px] or active:scale-[0.98] to simulate a physical push.
• BUTTON CONTRAST CHECK (mandatory, a11y): Before shipping any button, verify the button text is readable against the button background. White button + white text, bg-white CTA with text-white label, transparent button against the page background with no border -> all banned. Audit every CTA: contrast ratio WCAG AA min (4.5:1 for body, 3:1 for large text 18px+). Same rule applies to ghost buttons over photographic backgrounds (use a backdrop, scrim, or stroke).
• CTA BUTTON WRAP BAN (mandatory): Button text MUST fit on one line at desktop. If a label like "VIEW SELECTED WORK" wraps to 2 or 3 lines, the button is broken. Fix by EITHER shortening the label (3 words max for primary CTAs, ideally 1-2) OR widening the button. Wrapped CTAs at desktop are a Pre-Flight Fail.
• NO DUPLICATE CTA INTENT (mandatory): Two CTAs with the same intent on one page is a Pre-Flight Fail. "Get in touch" + "Contact us" + "Let's talk" + "Start a project" = all "contact" intent -> pick ONE label and use it everywhere (nav, hero, footer). Same for "Try free" + "Get started" + "Sign up free" (all "signup"), and "View work" + "See selected work" + "Browse projects" (all "portfolio"). One label per intent.
• FORM CONTRAST CHECK (mandatory, a11y): Form inputs, placeholder text, focus rings, helper text, and error text all pass WCAG AA contrast against the section background. Light placeholders on a near-white form, white form on white page section, labels grayer than 4.5:1 -> all banned. Audit every form before shipping. (Prefer Craft craft-text-input / craft-textarea / craft-select from Stacks UI so states come styled.)

4.6 Data & Form Patterns

• Label ABOVE input. Helper text optional but present in markup. Error text BELOW input. Standard gap-2 for input blocks.
• No placeholder-as-label. Ever.
• Reach for Stacks UI Craft form components (craft-text-input, craft-checkbox, craft-select) before hand-rolling inputs.

4.7 Layout Discipline (Hard Rules. Failing any of these is shipping broken work)

• Hero MUST fit in the initial viewport. Headline max 2 lines on desktop, subtext max 20 words AND max 3-4 lines, CTAs visible without scroll. If the copy is too long: reduce font scale OR cut copy. If you cannot describe the value-prop in 20 words of subtext, the value-prop is unclear, not the rule too tight. Never let the hero overflow and force scroll to find the CTA.
• Hero font-scale discipline. Plan font size and image size together. If the hero asset is large and the headline is more than 6 words, do not start at text-7xl/text-8xl. Default sensible range: text-4xl md:text-5xl lg:text-6xl for most heroes; text-6xl md:text-7xl only when the headline is 3-5 words. A 4-line hero headline is always a font-size error, never a copy-length error.
• HERO TOP PADDING CAP (mandatory): Hero top padding max pt-24 (about 6rem) at desktop. More than that means the hero content floats halfway down the viewport and reads as a layout bug, not intentional space. If your hero needs more breathing room, increase font scale or asset size, not top padding.
• HERO STACK DISCIPLINE (max 4 text elements). The hero is a single moment, not a feature list. Allowed text elements, max 4 in total:
  1. Eyebrow (small uppercase label) OR brand strip OR neither - pick zero or one
  2. Headline (max 2 lines, see above)
  3. Subtext (max 20 words, max 4 lines)
  4. CTAs (1 primary + max 1 secondary)
  • BANNED in the hero: tiny tagline below CTAs ("Works with GitHub, GitLab, and self-hosted Git"), trust micro-strip ("Used by engineering teams at..."), pricing teaser, feature bullet list, social-proof avatar row. All of those move to dedicated sections directly below the hero.
  • If you have an eyebrow AND a tagline below CTAs in the same hero, drop the tagline. One small text element per hero, max.
• "Used by" / "Trusted by" logo wall belongs UNDER the hero, never inside it. The hero is for the value prop and primary CTA. The logo wall is a separate section directly below.
• Navigation MUST render on a single line on desktop. If items don't fit at lg (1024px), condense labels, drop secondary items, or move to a hamburger (Stacks UI Disclosure / Menu). A two-line nav at desktop is broken design.
• Navigation height cap: 80px max desktop, default 64-72px. No huge "agency" nav bars that eat 15% of the viewport.
• Bento grids MUST have rhythm, not one-sided repetition. Do not stack 6 left-image / right-text rows. Vary the composition: alternate full-width feature rows, asymmetric tile sizes, vertical breaks.
• BENTO CELL COUNT RULE (mandatory): A bento grid has EXACTLY as many cells as you have content for. 3 items -> 3 cells. 5 items -> 5 cells. If your grid has an empty cell in the middle or at the end, you planned wrong. Re-shape the grid; do not paste a blank tile.
• Section-Layout-Repetition Ban. Once you use a layout family for a section (e.g. 3-column-image-cards, full-width-quote, split-text-image), that family can appear at most ONCE on the page. A landing page with 8 sections must use at least 4 different layout families.
• ZIGZAG ALTERNATION CAP (mandatory). Alternating "left-image + right-text" then "left-text + right-image" zigzag = banal. Max 2 sections in a row with this image+text-split pattern. The 3rd consecutive image+text split is a Pre-Flight Fail. Break the pattern with a full-width section, a vertical-stack section, a bento grid, a marquee, or a different layout family.
• EYEBROW RESTRAINT (mandatory, the #1 violated rule in production tests). An "eyebrow" is the small uppercase wide-tracking label sitting above a section headline (e.g. FOUR COLORWAYS, SELECTED WORK, THE HARDWARE). Typical CSS signature: text-[11px] uppercase tracking-[0.18em], font-mono text-[10.5px] uppercase tracking-[0.22em]. Every AI-built site puts an eyebrow above EVERY section header, producing the same templated rhythm. Hard rule:
  • Maximum 1 eyebrow per 3 sections. Hero counts as 1. So a page with 9 sections may use at most 3 eyebrows total.
  • If section A has an eyebrow, the next 2 sections cannot have one.
  • Pre-Flight Check is mechanical: count instances of uppercase tracking (or similar small-caps mono labels above headlines) across all section components. If count > ceil(sectionCount / 3), the output fails.
  • What to do instead of an eyebrow: drop it entirely. The headline alone is enough. The section's location on the page already categorizes it.
• SPLIT-HEADER BAN (mandatory). The pattern "left big headline + right small explainer paragraph" as a section header (left col-span-7/8, right col-span-4/5 with a small body paragraph floating in the right column) is banned as default. Sections should have ONE focused message. If you genuinely need both a headline and an explainer, stack them vertically (headline on top, body below, max-width 65ch). Reach for the split-header pattern only when the right column carries a real visual or interactive element, not just filler text.
• Bento Background Diversity (mandatory). Bento and feature-grid sections cannot be 6 white-on-white cards with text inside. At least 2-3 cells in any multi-cell grid need real visual variation: a real image, a brand-appropriate gradient (not AI-purple), a pattern, a tinted background.
• Mobile collapse must be explicit per section. For every multi-column layout, declare the < 768px fallback in the same component. No "it'll work, Crosswind handles it" assumptions.

4.8 Image & Visual Asset Strategy

Landing pages and portfolios are visual products. Text-only pages with fake-screenshot divs are slop.

Priority order for visual assets:

1. Image-generation tool first. If ANY image-gen tool is available in the environment you MUST use it to create section-specific assets: hero photography, product shots, texture backgrounds, mood images. Generate at the right aspect ratio for the section. Do not skip this step because hand-rolled CSS feels faster.
2. Real web images second. When no gen tool is available, use real photography sources. Acceptable defaults:
   • https://picsum.photos/seed/{descriptive-seed}/{w}/{h} for placeholder photography (seed should describe the section, e.g. marrow-cookware-kitchen)
   • Actual stock or brand URLs when the brief provides them
   • Open-license sources (Unsplash via direct URL, Pexels) if explicitly allowed
3. Last resort: tell the user. If neither is possible, do NOT fill the page with hand-rolled SVG illustrations or div-based "fake screenshots." Leave clearly-labeled placeholder slots (<!-- TODO: hero product photo, 1600x1200 -->) and at the end of the response say: "This page needs real images at: [list of placements]. Please generate or provide them."

Serve images correctly (Stacks): use standard <img> with explicit width/height to reserve space (avoid CLS). stx has an asset pipeline with image optimization; heavy asset handling goes through @stacksjs/storage. There is no next/image.

Even minimalist sites need real images. A pure-text page is not minimalism, it is incomplete work. Even an editorial Linear-style site needs at least 2-3 real images (hero, one product/lifestyle shot, one supporting image). Generate B&W minimalist photography if the brief is restrained; do not skip images because the dial is low.

Real company logos for social proof. When the brief calls for a "Trusted by / Used by / Customers" logo wall, do NOT default to plain text wordmarks. Use real SVG logos:

• Source: Simple Icons (https://cdn.simpleicons.org/{slug}/{color} for any color). Covers most known brands.
• Alternative: an Iconify brand collection (i-logos-*, i-simple-icons-*) rendered as a class.
• Made-up brand name? Then make-up an SVG mark too. Generate a simple monogram (one letter in a circle, two-letter ligature, abstract glyph) as an inline <svg> matching the page style. Plain text wordmarks for invented brands look generic.
• Always ensure logos render in both light and dark mode (white-on-dark, black-on-light, or a single-color theme variable).
• LOGO-ONLY rule (mandatory): logo wall = logos and nothing else. Do NOT print industry / category labels below each logo. The logo is the credibility. Optional: brand name as alt-text, optional link to the brand's site. That is it.

Hand-rolled illustrations:

• Iconify glyphs: fine (Section 3.C).
• Hand-rolled decorative SVGs (custom illustrations, logos, marks): strongly discouraged, never as default. Acceptable only when the brief explicitly calls for it, or it is a single simple geometric mark, and you are confident in the output quality.

Div-based fake screenshots are banned. A "hand-built product preview" rendered with <div> rectangles, fake task lists, fake dashboards, fake terminal windows is a Tell. To show a product: use a real screenshot URL, generate one, render a real mini-version of the actual UI, or skip the preview and use editorial photography.

Hero needs a real visual. Text + gradient blob is not a hero, it is a placeholder.

4.9 Content Density

Landing pages live on the first impression, not the full read. Cut ruthlessly.

• Default content shape per section: short headline (<= 8 words) + short sub-paragraph (<= 25 words) + one visual asset OR one CTA. Anything more must be justified by the section's job.

• No data-dump sections. A 20-row publication table, a 30-row award list, a giant pricing matrix on a marketing page = wrong layout. Use top 3-5 highlights + "View full list" link, a marquee/carousel for breadth, or a different page entirely if the data is the product.

• Long lists need a different UI component, not a longer list. Default <ul> with bullets / divide-y rows is the lazy choice. If you have > 5 items, reach for: a 2-column split with grouped items, a card grid with image + label, Tabs / Disclosure (Stacks UI) if items are categorisable, horizontal scroll-snap pills, a carousel, or a marquee. A spec sheet with 10 rows + a hairline under every row is the WORST default.

• Spec sheets specifically. A long product spec table with border-b on every row is the AI default for cookware / hardware / apparel / artisan briefs. Banned. Alternatives: a 2-col card grid (spec name + large display value + one-line "why it matters"), scroll-snap horizontal pills, grouped chunks (3 logical clusters, one soft divider each), or featured-vs-rest (3-4 hero specs as display tiles, the rest under a Stacks UI Disclosure).

• COPY SELF-AUDIT (mandatory before ship): Before declaring any task done, re-read every visible string (headlines, subheads, eyebrows, button labels, body copy, captions, alt text, footer text, error messages, including any {{ ... }} interpolations resolved). Flag any string that is:

  • Grammatically broken ("free on its past", "two plans but one is honest")
  • Has unclear referents ("we plan to stay that way" without prior context)
  • Sounds like AI hallucination (cute-but-wrong wordplay, forced metaphors, "elegant nothing" phrases)
  • Reads like an LLM trying to sound thoughtful (passive-aggressive humility, fake-craftsman labels, mock-poetic micro-meta) Rewrite every flagged string. If unsure whether a string makes sense, replace it with a plain functional sentence. AI-generated cute copy is worse than boring copy.

• Fake-precise numbers are flagged. Numbers like 92%, 4.1x, 48k, 5.8 mm, 13.4 lb either come from real data (fine), are explicitly labeled as mock (<!-- mock -->, fine), or are AI-invented spec aesthetics (banned). Don't fake engineering precision the brand doesn't claim.

• One copy register per page. Don't mix technical mono, editorial prose, and marketing punch in the same composition unless the brand voice explicitly calls for it.

4.10 Quotes & Testimonials

• Max 3 lines of quote body. Never 6. If the original quote is longer, cut it. A landing-page quote is a snippet, not the full review.
• For very small font sizes (footer-style testimonials) the line cap can stretch slightly. Spirit: "fits in a glance."
• No em-dashes inside the quote text as design flourish. See Section 9.G - em-dash is completely banned.
• Attribution: name + role + (optionally) company. Never name only ("- Sarah").
• Quote marks: use real typographic quotes ( " " ) or none at all. Not straight ASCII.

4.11 Page Theme Lock (Light / Dark Mode Consistency)

The page has ONE theme. Sections do not invert.

• If the page is dark mode, ALL sections are dark mode. No light-mode-warm-paper section sandwiched between dark sections (or vice versa). The user must not feel they walked into a different website mid-scroll.
• The exception: if the brief explicitly calls for a "Color Block Story" or "Theme Switch on Scroll" device AND that is a deliberate composition (one full theme switch with a strong transition, not random alternation), it is allowed once per page.
• Default behaviour: pick light, dark, or auto (prefers-color-scheme) at the page level and lock it. Section-level background tints within the same theme family are fine (bg-zinc-950 next to bg-zinc-900); flipping to bg-amber-50 in the middle of a bg-zinc-950 page is broken.
• Drive dark mode with the Crosswind dark: variant. If you offer a runtime toggle, set it ONCE at the layout/root level via useColorMode() / useDark() (see stacks-crosswind). Do not let individual sections override the theme.

5. CONTEXT-AWARE PROACTIVITY (Motion in Stacks)

These are tools, not defaults. Use them when the design read calls for them. None of these fire automatically.

Stacks ships NO motion library. There is no motion/react, no framer-motion, no gsap. All motion is built from three sources only:

1. Crosswind transitions + CSS keyframes in a <style> block (hover, micro-interactions, load-ins). Animate ONLY transform and opacity.
2. stx composables for observing state (useIntersectionObserver, useElementVisibility, useMouse, useMediaQuery, useResizeObserver, useWindow, useDeviceOrientation) - toggle a Crosswind class or set a CSS custom property.
3. CSS scroll-driven animations (animation-timeline: view() / scroll()) for pinned, stacked, and horizontal-pan effects - no script needed.

• Glassmorphism: Appropriate for premium consumer, Apple-adjacent, luxury, or media-overlay vibes. Inappropriate for dashboards, public-sector, "boring B2B." When used, go beyond backdrop-blur: add a 1px inner border (border-white/10) and a subtle inner shadow for physical edge refraction. Provide a solid-fill fallback under prefers-reduced-transparency (Appendix C).
• Magnetic Micro-physics: Use when MOTION_INTENSITY > 5 AND the brief reads premium / playful / agency. Implement by driving a CSS custom property from useMouse() inside an effect (Section 5.D). Never through per-frame signal state. See Section 3.B.
• Perpetual Micro-Interactions (Pulse, Typewriter, Float, Shimmer, Carousel): Use when MOTION_INTENSITY > 5 AND the section actively benefits from motion (status indicators, live feeds). Not every card needs an infinite loop. If a section is informational, leave it still. Prefer spring-like cubic-bezier easing over linear.
• "Motion claimed, motion shown." If MOTION_INTENSITY > 4, the page must actually move: entry transitions on hero, scroll-reveal on key sections, hover feedback on CTAs, at minimum. A static page that claims MOTION_INTENSITY: 7 is broken. Conversely, if you cannot ship working motion in scope, drop the dial to 3 and ship a clean static page. Never half-build motion that breaks (jumpy enters, missing observer cleanups).
• MOTION MUST BE MOTIVATED (mandatory). Before adding any animation, ask: "what does this communicate?" Valid answers: hierarchy, storytelling (sequenced reveal matching a narrative), feedback (acknowledging an action), state transition. Invalid answer: "it looked cool." Each scroll-driven section, each marquee, each pinned section needs a reason. If you cannot articulate it in one sentence, drop the animation.
• MARQUEE MAX-ONE-PER-PAGE (mandatory). Horizontal scrolling text marquees are appropriate at most ONCE per page. Two or more reads as lazy filler. Pick the one section where the marquee serves the content; the others get a different layout.
• Sticky-Stack Pattern (when scroll-stack is used). A "card stack on scroll" must be a REAL sticky-stack, not a sequential reveal list. See Section 5.A. Common failure: the reveal fires halfway through scroll instead of pinning at viewport top. Fix: pin with position: sticky; top: 0 so each card holds at the top of the viewport.
• Horizontal-Pan Pattern (when horizontal scroll is used). See Section 5.B. Common failure: the pan starts before the section is pinned so the user sees half a slide. Fix: pin the wrapper (`p

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