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 - **定位代码先用 `docs/code_index/index.md`**：按业务域渐进披露到具体文件；新增/删除/重命名文件时**必须同步更新对应域的索引文件**。
 - 总体架构 `docs/architecture.md`；后端规范 `docs/backend-guidelines.md`；前端规范 `docs/frontend-guidelines.md`；领域设计 `docs/domains/`；开发/部署排障 `docs/development.md`。
+- 视觉/交互规范 `docs/design-guidelines.md`（色彩 token、accent 预设、布局、卡片/表格/表单组件用法、加载/错误/409 交互态）——改 UI 前必读。
 - 规范性的行为契约仍以 `openspec/specs/` 为准；docs 是实现地图，不是需求来源。
 
 ## 布局与所有权
diff --git a/docs/design-guidelines.md b/docs/design-guidelines.md
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+# Design Guidelines
+
+Visual and interaction conventions for all three frontends. Everything here is
+enforced by `packages/shared/src/theme.css` tokens and `packages/ui`
+components — if you need a value that does not exist, extend the theme or the
+kit instead of improvising locally. No `<style scoped>`, no hex literals in
+app code.
+
+## Color
+
+Semantic tokens only (Tailwind classes: `bg-bg`, `text-text`, …):
+
+| Token | Value | Use |
+|---|---|---|
+| `bg` | `#f5f5f5` | page background |
+| `surface` | `#ffffff` | cards, panels, nav, inputs |
+| `border` | `#e2e5ea` | all borders/dividers |
+| `text` | `#1c2330` | primary text |
+| `muted` | `#66707f` | secondary text, placeholders |
+| `primary` | accent | actions, links, active states |
+| `danger` | `#d64545` | errors, destructive actions |
+| `success` | `#1f9d63` | success feedback, positive states |
+| `warning` | `#c77d0a` | pending/attention states |
+
+**Accent presets** (`red` default, `blue`, `teal`, `violet`) swap
+`--primary*` at runtime via `html[data-accent]`; users pick one with
+`VAccentSwatch`. Derivatives: `primary-hover`, `primary-soft` (subtle tint for
+selected/hover fills). Never reference a preset's hex directly.
+
+Opacity modifiers for tinted feedback: `bg-danger/10 text-danger` etc. (see
+`VBadge` tones).
+
+## Typography
+
+- Font: system stack (`--font-sans`, includes PingFang SC / Microsoft YaHei).
+- Page title: `text-xl font-bold` (`VPage` provides it).
+- Section heading: `text-base font-semibold` (consoles) /
+  `text-lg font-semibold` (mall content sections).
+- Body: `text-sm`; secondary/meta: `text-xs text-muted` (or `text-[13px]` in
+  dense console sidebars).
+- Bilingual copy renders through locale fallbacks, never side-by-side.
+
+## Radius, borders, elevation
+
+- Radius: `rounded-md` (8px) for cards/inputs/buttons; `rounded` (4px) for
+  chips/badges; `rounded-full` for avatars and progress bars.
+- Cards: `rounded-lg border border-border bg-surface shadow-sm` — this is
+  exactly `VCard`; use it instead of re-deriving.
+- Elevation: one level only (`shadow-sm` on cards). No stacked shadows.
+
+## Layout
+
+- Mall content max width: `max-w-mall` (1200px), centered, `px-4`.
+- Consoles: sidebar (`md:w-60`) + fluid `<main class="min-w-0 flex-1">`;
+  page content in `mx-auto w-full max-w-7xl px-4 md:px-6` (admin) or the
+  shop-admin equivalent. Content columns must be `w-full min-w-0` — auto
+  margins on grid items silently shrink them to fit-content.
+- Buyer center (`apps/mall/pages/user.vue`): `234px` sidebar + fluid content
+  in a `max-w-mall` grid.
+
+## Components and when to use them
+
+| Need | Use | Notes |
+|---|---|---|
+| Page shell | `VPage` (`:title`, `#actions`) | consoles |
+| Card/section | `VCard` (`:padded="false"` for edge-to-edge tables) | one card per logical section |
+| Button | `VBtn` (`variant`: default/primary/danger, `size`: md/sm) | primary = the one forward action; danger only for destructive |
+| Badge/status | `VBadge` (`tone`: green/blue/orange/red/gray) | map domain status → tone once per page |
+| Form field | `VField` (`:label`, `:error`) + `VInput` | errors inline, never alert() |
+| Table | `VTable` in `overflow-x-auto` wrapper | dense console data |
+| Empty state | `UiEmptyState` (mall) / muted text (consoles) | always provide one |
+| Pagination | `UiPagination` (mall) / prev-next block (consoles) | server-driven totals |
+
+## Interaction states (every async surface)
+
+1. **Loading**: muted text/skeleton region; never a blank card.
+2. **Error**: `role="alert"` + `text-danger`, keep user input intact.
+3. **Success**: transient `role="status"` text near the action
+   (`text-success`), not a toast system.
+4. **Conflict (409)**: show the message and refresh from server state —
+   the UI must converge to truth, not stack retries.
+5. **Destructive actions**: `confirm()` + `VBtn variant="danger"`.
+
+## Imagery and icons
+
+- Product/content images: `object-cover` in fixed-ratio boxes
+  (`h-12 w-20` thumbnails, `w-full` heroes).
+- Icons: inline SVG path data (storefront quick links carry glyphs in the
+  API). No icon font, no emoji as UI icons.
+- Avatars: `rounded-full`, fallback `/mock/avatar.svg`.
+
+## Accessibility floor
+
+- All controls keyboard-reachable; visible focus via
+  `focus:border-primary focus:outline-2 focus:outline-primary/30` (built into
+  `VInput`).
+- Icon-only buttons need an accessible name; star ratings use
+  `role="img"` + `aria-label`.
+- Respect locale switching without layout overflow (`min-w-0`, `truncate`).
+
+## What stays out of scope
+
+Charts, drag-and-drop builders, dark mode, and print styles have no tokens
+yet. Propose them as a design extension (new tokens in `theme.css` + kit
+components) instead of local one-offs.