fix(ui): keep mobile onboarding and login usable

Hide the dead composer during birth-time intake, replace internal
copy with user-facing hints, and keep short-screen login, location
search, and session history reachable on phones.

frontend/src/app/globals.css

@@ -274,8 +274,9 @@ button:disabled { cursor: default; opacity: .45; }
 @media (max-width: 767px) {
   .brand-row { padding: 0 4px; }
   .brand-mark { width: 26px; height: 26px; }
-  .session-nav { overflow: hidden; }
+  .session-nav { overflow: visible; }
   .session-list { overflow-x: clip; }
+  [data-sidebar="content"] { -webkit-overflow-scrolling: touch; }
   .chat-header > div { min-width: 0; flex: 1; }
   .chat-header strong { max-width: 100%; }
   .onboarding-card { padding: 16px; }
@@ -294,8 +295,7 @@ button:disabled { cursor: default; opacity: .45; }
   .profile-grid, .location-grid, .code-form { grid-template-columns: 1fr; }
   .code-form .note-field { grid-column: auto; }
   .code-form .button-primary { width: 100%; }
-  .auth-page { padding: 16px; }
-  .auth-brand { margin-bottom: 32px; }
+  .auth-brand { margin-bottom: var(--space-6); }
 }
 
 @media (prefers-reduced-motion: reduce) {
@@ -825,8 +825,8 @@ button:disabled { cursor: default; opacity: .45; }
 .synastry-history-item { display: grid; gap: 3px; padding: var(--space-3); border: 1px solid var(--color-border); border-radius: var(--radius-md); background: var(--color-canvas); color: var(--color-ink); text-align: left; }
 .synastry-history-item small { color: var(--color-ink-secondary); font-size: var(--type-caption); }
 
-input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input), select:not([class^="ant-"]):not([class*=" ant-"]) { width: 100%; min-height: 44px; padding: 0 12px; border: 1px solid var(--color-border-strong); color: var(--color-ink); border-color: var(--color-border-strong); border-radius: var(--radius-md); background: var(--color-canvas); font-size: 14px; }
-input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled, select:not([class^="ant-"]):not([class*=" ant-"]):disabled { color: var(--color-ink-tertiary); background: var(--color-canvas-muted); }
+input:not([type="radio"]):not([type="checkbox"]):not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input), select:not([class^="ant-"]):not([class*=" ant-"]) { width: 100%; min-height: 44px; padding: 0 12px; border: 1px solid var(--color-border-strong); color: var(--color-ink); border-color: var(--color-border-strong); border-radius: var(--radius-md); background: var(--color-canvas); font-size: 14px; }
+input:not([type="radio"]):not([type="checkbox"]):not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled, select:not([class^="ant-"]):not([class*=" ant-"]):disabled { color: var(--color-ink-tertiary); background: var(--color-canvas-muted); }
 .button-primary, .button-secondary { min-height: 44px; display: inline-flex; align-items: center; justify-content: center; padding: 0 15px; border: 1px solid var(--color-action); cursor: pointer; text-decoration: none; transition: background-color 120ms ease-out, color 120ms ease-out, transform 120ms ease-out; border-radius: var(--radius-md); font-size: 14px; font-weight: 500; }
 .button-primary { border-color: var(--color-action); background: var(--color-action); color: var(--color-on-dark); }
 .button-secondary { border-color: var(--color-border-strong); background: var(--color-canvas); color: var(--color-ink); }
@@ -925,17 +925,19 @@ input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled
   .message-list { width: 100%; padding: var(--space-5) var(--space-4) var(--space-12); }
   .message-content { max-width: 88%; }
   .composer-wrap { padding: var(--space-2) var(--space-3) max(var(--space-3), env(safe-area-inset-bottom)); }
+  :root { --composer-reserve: 116px; }
+  .location-combobox-results { position: static; top: auto; max-height: min(240px, 42dvh); margin-top: var(--space-2); box-shadow: none; }
   .account-modal { max-height: calc(100dvh - var(--space-8)); padding: var(--space-6); }
   .profile-modal .account-modal-header { margin: calc(var(--space-6) * -1) calc(var(--space-6) * -1) var(--space-4); padding: var(--space-6) var(--space-6) var(--space-4); }
   .avatar-editor { grid-template-columns: 72px minmax(0, 1fr); gap: var(--space-4); }
   .avatar-editor > .user-avatar { width: 72px !important; height: 72px !important; }
   .avatar-palette-list { grid-template-columns: repeat(2, minmax(64px, 1fr)); }
-  .auth-page { padding: 0; }
-  .auth-shell { min-height: 100dvh; grid-template-columns: 1fr; grid-template-rows: auto 1fr; border-radius: 0; box-shadow: none; }
-  .auth-story { min-height: 248px; padding: var(--space-8) var(--space-6); }
+  .auth-page { height: 100dvh; overflow-x: hidden; overflow-y: auto; -webkit-overflow-scrolling: touch; padding: 0; }
+  .auth-shell { min-height: 100%; overflow: visible; align-content: start; grid-template-columns: 1fr; grid-template-rows: auto auto; border-radius: 0; box-shadow: none; }
+  .auth-story { min-height: 0; justify-content: flex-start; gap: var(--space-3); padding: var(--space-6) var(--space-6) var(--space-5); }
   .auth-story h2 { max-width: 560px; margin: var(--space-3) 0 0; font-size: var(--type-display-sm); }
   .auth-story > div > p, .auth-footnote { display: none; }
-  .auth-panel { padding: var(--space-8) var(--space-6); }
+  .auth-panel { justify-content: flex-start; padding: var(--space-8) var(--space-6) max(var(--space-8), env(safe-area-inset-bottom)); }
   .auth-panel h1 { font-size: var(--type-display-md); }
   .admin-header { padding: 0 var(--space-4); }
   .admin-scroll { padding: var(--space-6) var(--space-4) var(--space-12); }
@@ -959,15 +961,20 @@ input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled
   .paywall-footer > a, .paywall-footer > button { width: 100%; }
   .dialog-actions { flex-direction: column-reverse; }
   .dialog-actions > button { width: 100%; }
-  .auth-story { min-height: 220px; padding: var(--space-6) var(--space-5); }
-  .auth-story h2 { font-size: var(--type-display-sm); }
-  .auth-panel { padding: var(--space-8) var(--space-5); }
+  .auth-story { min-height: 0; padding: var(--space-5); }
+  .auth-story h2 { font-size: var(--type-title-lg); }
+  .auth-panel { padding: var(--space-6) var(--space-5) max(var(--space-6), env(safe-area-inset-bottom)); }
   .auth-panel h1 { font-size: var(--type-display-sm); }
   .admin-section { padding: var(--space-5); }
 }
 .session-delete-overlay { z-index: 100; }
 .session-delete-confirmation p { margin: 0; color: var(--color-ink-secondary); }
 
+@media (max-width: 767px) and (max-height: 640px) {
+  .auth-story { display: none; }
+  .auth-brand { display: flex; margin-bottom: var(--space-6); }
+}
+
 @media (max-width: 430px) {
   [data-sonner-toaster] { right: var(--space-4) !important; left: var(--space-4) !important; width: auto !important; }
   .conversational-rectification { width: 100%; max-width: 100%; gap: var(--space-4); overflow-x: clip; }
@@ -1571,18 +1578,36 @@ input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled
 .onboarding-card-heading b { font-size: clamp(22px, 2.6vw, 30px); letter-spacing: -.03em; }
 .onboarding-card-heading small { max-width: 260px; color: var(--color-ink-secondary); line-height: 1.55; font-size: var(--type-caption); text-wrap: pretty; }
 .birth-time-intake { gap: var(--space-6); }
+.conversation.is-onboarding-form { align-content: start; padding-bottom: var(--space-8); }
+.conversation.is-onboarding-form .welcome { padding-top: var(--space-6); padding-bottom: var(--space-8); }
+.conversation.is-onboarding-form .welcome > .onboarding-message:first-child { padding-bottom: var(--space-3); }
+.conversation.is-onboarding-form .welcome > .onboarding-message:first-child .message-bubble p {
+  max-width: 680px;
+  font-size: var(--type-title-md);
+  letter-spacing: -.2px;
+  line-height: 1.4;
+}
 .birth-time-source-fieldset { padding-top: var(--space-5); border-top: 1px solid var(--color-border); }
-.birth-time-source-fieldset legend { margin-bottom: 5px; color: var(--color-ink); font-size: var(--type-title-sm); font-weight: 700; }
+.birth-time-source-fieldset legend {
+  display: block;
+  float: none;
+  width: 100%;
+  margin: 0 0 5px;
+  padding: 0;
+  color: var(--color-ink);
+  font-size: var(--type-title-sm);
+  font-weight: 700;
+}
 .birth-time-source-intro { margin: 0 0 var(--space-3); color: var(--color-ink-secondary); font-size: var(--type-caption); line-height: 1.55; }
-.birth-time-source-list { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-3); }
-.birth-time-source-option { min-height: 118px; grid-template-columns: 20px minmax(0, 1fr); align-items: start; gap: var(--space-3); padding: 18px; border-color: var(--color-border); border-radius: var(--radius-md); background: var(--color-canvas-soft); transition: border-color 160ms ease-out, background-color 160ms ease-out; }
+.birth-time-source-list { grid-template-columns: 1fr; gap: var(--space-2); }
+.birth-time-source-option { min-height: 64px; grid-template-columns: 18px minmax(0, 1fr); align-items: center; gap: var(--space-3); padding: var(--space-3) var(--space-4); border-color: var(--color-border); border-radius: var(--radius-md); background: var(--color-canvas); transition: border-color 160ms ease-out, background-color 160ms ease-out; }
 .birth-time-source-option:hover { border-color: color-mix(in srgb, var(--color-action) 44%, var(--color-border)); }
 .birth-time-source-option.is-selected { border-color: var(--color-action); background: var(--color-action-soft); box-shadow: inset 0 0 0 1px var(--color-action); }
-.birth-time-source-option input { appearance: none; position: relative; width: 16px; min-width: 16px; height: 16px; min-height: 16px; margin: 3px 0 0; border: 1.5px solid var(--color-border-strong); border-radius: 50%; background: var(--color-canvas); }
+.birth-time-source-option input { appearance: none; align-self: center; justify-self: center; position: static; box-sizing: border-box; width: 16px; min-width: 16px; max-width: 16px; height: 16px; min-height: 16px; max-height: 16px; margin: 0; overflow: visible; clip: auto; clip-path: none; border: 1.5px solid var(--color-border-strong); border-radius: 50%; background: var(--color-canvas); }
 .birth-time-source-option input:checked { border-color: var(--color-action); background: var(--color-action); box-shadow: inset 0 0 0 4px var(--color-action-soft); }
-.birth-time-source-option > span { gap: 7px; }
-.birth-time-source-option b { font-size: var(--type-title-sm); line-height: 1.3; }
-.birth-time-source-option small { font-size: var(--type-body-sm); line-height: 1.55; }
+.birth-time-source-option > span { gap: 4px; }
+.birth-time-source-option b { font-size: var(--type-body-sm); line-height: 1.35; }
+.birth-time-source-option small { font-size: var(--type-caption); line-height: 1.5; }
 .birth-time-detail-grid { grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: var(--space-3); padding: var(--space-4); border: 1px solid var(--color-border); border-radius: var(--radius-lg); background: var(--color-canvas-soft); }
 .birth-time-period-details { align-items: start; }
 .birth-time-period-details > label { align-self: start; }
@@ -1650,8 +1675,7 @@ input:not([class^="ant-"]):not([class*=" ant-"]):not(.ant-picker input):disabled
 .select-item-indicator { display: inline-flex; flex: 0 0 auto; color: var(--color-action); }
 @keyframes select-content-in { from { opacity: 0; transform: translateY(-3px) scale(.98); } to { opacity: 1; transform: translateY(0) scale(1); } }
 
-.birth-time-source-option { grid-template-columns: minmax(0, 1fr); }
-.birth-time-source-option input { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap; }
+.birth-time-source-option { grid-template-columns: 18px minmax(0, 1fr); }
 .birth-time-source-option:focus-within { border-color: var(--color-action); outline: none; box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-action) 16%, transparent); }
 .birth-time-source-option.is-selected:focus-within { box-shadow: inset 0 0 0 1px var(--color-action), 0 0 0 3px color-mix(in srgb, var(--color-action) 16%, transparent); }
 .birth-time-source-option > span { min-width: 0; }

frontend/src/app/layout.tsx

@@ -1,4 +1,4 @@
-import type { Metadata } from "next";
+import type { Metadata, Viewport } from "next";
 import Script from "next/script";
 import { Toaster } from "@/components/ui/sonner";
 import "./globals.css";
@@ -9,6 +9,13 @@ export const metadata: Metadata = {
   description: "与 Mastra Agent 对话，基于星盘证据讨论事业、关系与时间窗口。",
 };
 
+export const viewport: Viewport = {
+  width: "device-width",
+  initialScale: 1,
+  viewportFit: "cover",
+  interactiveWidget: "resizes-content",
+};
+
 export default function RootLayout({ children }: Readonly<{ children: React.ReactNode }>) {
   const enableReactDevTools = process.env.NODE_ENV === "development"
     && process.env.NEXT_PUBLIC_ENABLE_REACT_DEVTOOLS === "1";

frontend/src/app/page.tsx

@@ -52,6 +52,7 @@ import {
   describeBirthTimeDraft,
   isDeclaredBirthProfileComplete,
   isBirthTimeDraftReady,
+  birthTimeDraftReadyHint,
   normalizePersistedBirthDate,
   type BirthTimeDraft,
   type BirthTimeSource,
@@ -1255,6 +1256,8 @@ export default function Home() {
     && !onboardingPending
     && !rectificationSurfaceOpen
     && !activeSession?.messages.length;
+  const onboardingFormActive = !profileComplete && onboardingStep !== "name";
+  const birthTimeContinueHint = onboardingStep === "birth" ? birthTimeDraftReadyHint(profileDraft) : "";
   const daypartGreeting = greetingForHour(new Date().getHours());
 
   function restoreConsultationRecovery(session: ChatSession, requestId: string) {
@@ -3257,7 +3260,7 @@ export default function Home() {
           </header>
 
         {!rectificationSurfaceOpen && (
-          <div ref={conversation} className={`conversation ${activeSession?.messages.length ? "" : "is-empty"}`}>
+          <div ref={conversation} className={`conversation ${!activeSession?.messages.length && !onboardingFormActive ? "is-empty" : ""} ${onboardingFormActive ? "is-onboarding-form" : ""}`}>
             {!activeSession?.messages.length ? (
             <div className="welcome">
               {!profileComplete ? (
@@ -3287,6 +3290,7 @@ export default function Home() {
                         <BirthTimeIntakeFields value={profileDraft} onPatch={(patch) => setProfileDraft((current) => applyBirthTimeDraftPatch(current, patch))} />
                         {accountError && <p className="form-error" role="alert">{accountError}</p>}
                         <div className="onboarding-card-actions">
+                          {birthTimeContinueHint ? <p className="onboarding-card-action-hint">{birthTimeContinueHint}</p> : <span />}
                           <button className="button-primary" type="submit" disabled={profileSaving || !isBirthTimeDraftReady(profileDraft)}>{profileSaving ? "保存中" : "继续"}</button>
                         </div>
                       </fieldset>
@@ -3460,7 +3464,7 @@ export default function Home() {
           />
         )}
 
-        {!rectificationSurfaceOpen && <div className={`composer-wrap ${starterHomeVisible ? "composer-wrap-starter" : ""}`}>
+        {!rectificationSurfaceOpen && !onboardingFormActive && <div className={`composer-wrap ${starterHomeVisible ? "composer-wrap-starter" : ""}`}>
           {activeSuggestions.length > 0 && (
             <div className="composer-suggestions" aria-label="推荐继续提问">
               {activeSuggestions.map((question) => (

frontend/src/components/birth-time-intake.tsx

@@ -85,7 +85,7 @@ export function BirthTimeIntakeFields({ value, onPatch }: BirthTimeIntakeProps)
         <section className="birth-time-profile-result" aria-label="生时校正结果">
           <div className="birth-time-profile-result-heading">
             <span>出生时间记录</span>
-            <strong>{displayState.kind === "candidate" ? "候选时间" : displayState.kind === "accepted" ? "校正采用" : "引擎确认"}</strong>
+            <strong>{displayState.kind === "candidate" ? "候选时间" : displayState.kind === "accepted" ? "校正采用" : "已记录时间"}</strong>
           </div>
           <dl>
             <div>
@@ -101,7 +101,7 @@ export function BirthTimeIntakeFields({ value, onPatch }: BirthTimeIntakeProps)
             <p>这仍是未确认候选，不会自动成为出生分钟；{birthTimeConsultationOptionsCopy(value)}</p>
           )}
           {displayState.kind === "accepted" && (
-            <p>这是你从候选中选择的校正采用时间，并非引擎唯一确认分钟；后续排盘会使用它。</p>
+            <p>这是你从候选中选择的校正采用时间，不是外部档案确认的出生时间；后续排盘会使用它。</p>
           )}
         </section>
       )}

frontend/src/lib/birth-time-intake-model.ts

@@ -83,8 +83,8 @@ export function formatBirthDate(value: Date): string {
 }
 
 export const birthTimeSourceOptions = [
-  { value: "family_exact", label: "我知道准确出生时间", hint: "保存为初始化填报时间，不会自动标记为引擎确认" },
-  { value: "period_only", label: "我不确定准确时间", hint: "告诉我们大致时段；完全不清楚也可以直接跳过" },
+  { value: "family_exact", label: "我知道准确出生时间", hint: "按医院记录或家人记得的时间填写，精确到分钟" },
+  { value: "period_only", label: "我不确定准确时间", hint: "只知道大概几点、上午下午，或完全不清楚" },
 ] as const;
 
 export const birthTimeSourceDefaults = {
@@ -223,6 +223,15 @@ export function isBirthTimeDraftReady(draft: BirthTimeDraft) {
   }
 }
 
+export function birthTimeDraftReadyHint(draft: BirthTimeDraft) {
+  if (!parseBirthDate(draft.date)) return "请先选择出生日期";
+  if (!draft.birthTimeSource) return "请选择你对出生时间了解多少";
+  if (isBirthTimeDraftReady(draft)) return "";
+  if (draft.birthTimeSource === "period_only") return "请选择一个大致时段";
+  if (draft.birthTimeSource === "unknown") return "";
+  return "请填写时和分";
+}
+
 /**
  * Whether the user has finished declaring what they actually know about birth time.
  * This is an onboarding condition, not a claim that an exact chart minute is ready.