fix(client): register semantic font-size tokens in tailwind-merge (cn)

extendTailwindMerge teaches cn() the custom text-caption/body/h1... tokens as a font-size group (v1.x config shape) so a size + a color in the same cn() call no longer drop the size; gallery Modal/ConfirmDialog sections + kit updates.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/frontend/client/src/pages/_gallery/GalleryApp.tsx

@@ -77,7 +77,7 @@ export default function GalleryApp() {
                   key={p.id}
                   onClick={() => setActiveId(p.id)}
                   className={cn(
-                    'flex w-full items-center gap-2 rounded-lg px-3 py-2 text-left text-body-sm transition-colors',
+                    'flex w-full items-center gap-2 rounded-lg px-3 py-2 text-left text-body transition-colors',
                     activeId === p.id
                       ? 'bg-blue-500/[0.08] font-medium text-text-primary'
                       : 'text-muted-foreground hover:bg-muted/60',

src/frontend/client/src/pages/_gallery/components/kit.tsx

@@ -49,7 +49,7 @@ export function ComponentPage({
           <h2 className="mb-3 text-h3 text-text-primary">何时使用 / 规则</h2>
           <ul className="space-y-2 rounded-xl border border-border-light bg-muted/20 p-5">
             {whenToUse.map((item, i) => (
-              <li key={i} className="flex gap-2 text-body-sm text-text-primary">
+              <li key={i} className="flex gap-2 text-body text-text-primary">
                 <span className="mt-2 size-1.5 shrink-0 rounded-full bg-blue-500" />
                 <span>{item}</span>
               </li>
@@ -168,9 +168,9 @@ export function CompareTable({
 }
 
 /* ------------------------------------------------------------------ *
- * Legacy aliases — kept so not-yet-migrated sections still compile.
- * New pages should use ComponentPage / ExampleGroup / ExampleCard / ExampleGrid.
- * TODO(gallery): migrate Modal / ConfirmDialog sections to the new template.
+ * Legacy aliases — Demo / DemoGrid are still used by migrated pages
+ * (they now forward to ExampleCard / ExampleGrid). Section is unused by
+ * gallery pages (all migrated to ComponentPage) but kept as a safety net.
  * ------------------------------------------------------------------ */
 
 /** @deprecated use ExampleGroup inside a ComponentPage. */

src/frontend/client/src/pages/_gallery/sections/ConfirmDialogSection.tsx

@@ -12,7 +12,7 @@ import { OGDialog, OGDialogTrigger } from '~/components/ui/OriginalDialog';
 import OGDialogTemplate from '~/components/ui/OGDialogTemplate';
 import { Label } from '~/components/ui/Label';
 import { useConfirm } from '~/Providers';
-import { Section, Demo, DemoGrid, CompareTable } from '../components/kit';
+import { ComponentPage, ExampleGroup, Demo, DemoGrid, CompareTable } from '../components/kit';
 
 /** Demos for the app-wide `useConfirm()` service (ConfirmContext, AlertDialog-based). */
 function UseConfirmDemos() {
@@ -87,7 +87,7 @@ function ConfirmDemo({
           title={title}
           className="max-w-[450px]"
           main={
-            <Label className="text-left text-sm font-medium">{body}</Label>
+            <Label className="text-left text-body font-medium">{body}</Label>
           }
           selection={{
             selectHandler: () => undefined,
@@ -103,10 +103,10 @@ function ConfirmDemo({
 
 export function ConfirmDialogSection() {
   return (
-    <Section
-      id="confirm"
+    <ComponentPage
       title="二次确认弹窗"
-      subtitle={
+      eng="Confirm Dialog"
+      description={
         <>
           删除/危险操作时的「确认 / 取消」小弹窗。两套体系：旧页面走{' '}
           <code>OGDialogTemplate selection</code>（剩 13 文件：7 处死 UI 确认 + 6 处表单弹窗），新页面走{' '}
@@ -116,9 +116,14 @@ export function ConfirmDialogSection() {
           （另有 9 个文件手拼 <code>AlertDialog</code> —— 属于普通弹窗，归 Modal 改造范围，本期不动。）
         </>
       }
+      whenToUse={[
+        <>危险操作（删除等）用 <code>useConfirm()</code>：<code>variant: destructive</code>（红）/ <code>default</code>（橙色警示）。</>,
+        <>确认按钮只两档：danger <code>#f53f3f</code> / primary 主色（<code>selectVariant</code> 指定）；特例走 <code>selectClasses</code> 口子。</>,
+        <>壳：圆角 16 / p-5 / 灰底毛玻璃；取消按钮白底描边。B 套已对齐 C 套基准。</>,
+      ]}
     >
-      {/* The three coexisting confirm-dialog systems */}
-      <div className="mb-6">
+      {/* The two coexisting confirm-dialog systems */}
+      <ExampleGroup title="现状：两套确认体系">
         <CompareTable
           head={['体系', '实现', '业务文件数', '用在哪', '样式一致性']}
           rows={[
@@ -142,10 +147,10 @@ export function ConfirmDialogSection() {
             ],
           ]}
         />
-      </div>
+      </ExampleGroup>
 
       {/* Inventory table: every selectClasses variant found in business code */}
-      <div className="mb-6">
+      <ExampleGroup title="确认按钮 selectClasses 清单（9 种历史写法）">
         <CompareTable
           head={['#', '确认按钮 selectClasses（原文）', '用处', '文件数']}
           rows={[
@@ -209,10 +214,10 @@ export function ConfirmDialogSection() {
             ],
           ]}
         />
-      </div>
+      </ExampleGroup>
 
       {/* Anatomy after step-1 convergence — B shell/buttons now mirror the C look */}
-      <div className="mb-6">
+      <ExampleGroup title="对齐后的规格（B 套 = C 套）">
         <CompareTable
           head={['部位', '对齐后的值（B 套 = C 套）', '备注']}
           rows={[
@@ -251,9 +256,10 @@ export function ConfirmDialogSection() {
             ],
           ]}
         />
-      </div>
+      </ExampleGroup>
 
-      <DemoGrid cols={3}>
+      <ExampleGroup title="逐个打开对比（旧写法现应呈现统一外观）">
+        <DemoGrid cols={3}>
         <UseConfirmDemos />
         <ConfirmDemo
           label="① red-700 系（6 处，原 8）"
@@ -317,6 +323,7 @@ export function ConfirmDialogSection() {
           selectClasses="btn btn-primary"
         />
       </DemoGrid>
-    </Section>
+      </ExampleGroup>
+    </ComponentPage>
   );
 }

src/frontend/client/src/pages/_gallery/sections/ModalSection.tsx

@@ -34,12 +34,12 @@ import {
 import DialogTemplate from '~/components/ui/DialogTemplate';
 import OGDialogTemplate from '~/components/ui/OGDialogTemplate';
 import { useConfirm } from '~/Providers';
-import { Section, Demo, DemoGrid, CompareTable } from '../components/kit';
+import { ComponentPage, ExampleGroup, Demo, DemoGrid, CompareTable } from '../components/kit';
 
 /** Identical body for every shell so only the shell itself differs. */
 const demoBody = (
   <div className="flex flex-col gap-3">
-    <p className="text-sm text-text-primary">
+    <p className="text-body text-text-primary">
       这里是弹窗正文示例。观察内边距、行距与正文和标题/按钮的间距。
     </p>
     <Input placeholder="示例输入框" />
@@ -68,22 +68,24 @@ function ConfirmReferenceDemo() {
 
 export function ModalSection() {
   return (
-    <Section
-      id="modal"
+    <ComponentPage
       title="Modal 弹窗"
-      subtitle={
+      eng="Modal"
+      description={
         <>
           2026-07-09 重新盘点：全站普通弹窗共 <b>5 个并行体系、约 64 个业务文件</b>
           。二次确认期已把 B 套壳对齐 C 套视觉，但 A 套（原语直接拼 22 处 + 模板 3
           处）与手拼 AlertDialog（7 处）仍是另外两种壳。逐个打开对比，定统一标准。
         </>
       }
+      whenToUse={[
+        <>本页是<b>现状盘点</b>，统一标准尚未定稿（见文末"④ 待设计师定夺"）。</>,
+        <>已定：二次确认（C 套）壳为基准候选——圆角 16 / p-5 / 灰底毛玻璃；B 套已对齐。</>,
+        <>待定：A 套（最大人群 22 处）的遮罩 / 圆角 / 标题字重是否并入基准。</>,
+      ]}
     >
       {/* ① Population overview */}
-      <h3 className="mb-3 mt-2 text-base font-semibold text-text-primary">
-        ① 用量盘子（当前精确扫描，排除 ui/ 与画廊）
-      </h3>
-      <div className="mb-8">
+      <ExampleGroup title="① 用量盘子（当前精确扫描，排除 ui/ 与画廊）">
         <CompareTable
           head={['体系', '实现', '业务文件数', '用在哪 / 备注']}
           rows={[
@@ -125,13 +127,10 @@ export function ModalSection() {
             ],
           ]}
         />
-      </div>
+      </ExampleGroup>
 
       {/* ② Shell anatomy */}
-      <h3 className="mb-3 text-base font-semibold text-text-primary">
-        ② 壳样式解剖（源码当前真实值）
-      </h3>
-      <div className="mb-8">
+      <ExampleGroup title="② 壳样式解剖（源码当前真实值）">
         <CompareTable
           head={['维度', 'A 套 Dialog', 'B 套 OriginalDialog（已对齐 C 套）', 'AlertDialog（手拼底座）']}
           rows={[
@@ -182,13 +181,10 @@ export function ModalSection() {
             ],
           ]}
         />
-      </div>
+      </ExampleGroup>
 
       {/* ③ Side-by-side demos — identical content, different shells */}
-      <h3 className="mb-3 text-base font-semibold text-text-primary">
-        ③ 同一内容装进各个壳（逐个打开对比）
-      </h3>
-      <div className="mb-8">
+      <ExampleGroup title="③ 同一内容装进各个壳（逐个打开对比）">
         <DemoGrid cols={3}>
           {/* A-set raw primitives — the largest population */}
           <Demo label="A 套 · 原语直接拼（22 处）" note="ui/Dialog.tsx · 浅黑毛玻璃 · 圆角8 · p-5">
@@ -278,7 +274,7 @@ export function ModalSection() {
               </AlertDialogTrigger>
               <AlertDialogContent className="max-w-md">
                 {/* Business pages hand-roll header/footer like this (ChannelMemberDialog etc.) */}
-                <h3 className="text-base font-medium text-text-primary">弹窗标题</h3>
+                <h3 className="text-h4 text-text-primary">弹窗标题</h3>
                 {demoBody}
                 <div className="flex justify-end gap-2">
                   <Button variant="outline">取消</Button>
@@ -296,11 +292,11 @@ export function ModalSection() {
             <ConfirmReferenceDemo />
           </Demo>
         </DemoGrid>
-      </div>
+      </ExampleGroup>
 
       {/* ④ Decision checklist */}
-      <h3 className="mb-3 text-base font-semibold text-text-primary">④ 待设计师定夺</h3>
-      <div className="rounded-xl border border-border-light bg-muted/20 p-5 text-sm leading-7 text-text-primary">
+      <ExampleGroup title="④ 待设计师定夺">
+      <div className="rounded-xl border border-border-light bg-muted/20 p-5 text-body text-text-primary">
         <ol className="list-decimal space-y-1 pl-5">
           <li>
             <b>遮罩</b>：A 套浅黑毛玻璃（black/40+blur） vs B/C 套灰白毛玻璃（gray-500/90+blur）？
@@ -330,6 +326,7 @@ export function ModalSection() {
           </li>
         </ol>
       </div>
-    </Section>
+      </ExampleGroup>
+    </ComponentPage>
   );
 }

src/frontend/client/src/utils/cn.ts

@@ -1,6 +1,29 @@
-import { twMerge } from 'tailwind-merge';
+import { extendTailwindMerge } from 'tailwind-merge';
 import { type ClassValue, clsx } from 'clsx';
 
+/**
+ * twMerge taught about the project's custom semantic font-size tokens
+ * (see docs 基础-字体规范.md §7 / theme.extend.fontSize in tailwind.config.cjs).
+ *
+ * Why this is required: tailwind-merge's `text-*` handling treats any UNKNOWN
+ * `text-X` as a text COLOR (catch-all). So `text-body` / `text-h1` / `text-caption`
+ * … are mis-grouped as colors, and when a real color (e.g. `text-text-primary`)
+ * appears in the SAME cn() call, the font size is silently dropped → element
+ * falls back to the inherited 16px. Registering them in the `font-size` group
+ * makes cn() preserve size + color together, and collapse size-vs-size correctly.
+ *
+ * NOTE: this uses the tailwind-merge **v1.x** config shape (`classGroups` at the
+ * top level). v2+ nests it under `extend` — do not copy a v2 snippet here while
+ * the dependency is pinned to ^1.14.0.
+ */
+const twMerge = extendTailwindMerge({
+  classGroups: {
+    'font-size': [
+      { text: ['caption', 'body-sm', 'body', 'h1', 'h2', 'h3', 'h4', 'display', 'metric'] },
+    ],
+  },
+});
+
 /**
  * Merges the tailwind clases (using twMerge). Conditionally removes false values
  * @param inputs The tailwind classes to merge