diff --git a/ai_knowledge_base_v2/apps/user-client/package-lock.json b/ai_knowledge_base_v2/apps/user-client/package-lock.json
index 05c4a63..3f33c1f 100644
--- a/ai_knowledge_base_v2/apps/user-client/package-lock.json
+++ b/ai_knowledge_base_v2/apps/user-client/package-lock.json
@@ -8,6 +8,7 @@
       "name": "ai-kb-user-client",
       "version": "0.1.0",
       "dependencies": {
+        "@lucide/vue": "^1.24.0",
         "@types/markdown-it": "^14.1.2",
         "@vitejs/plugin-vue": "^6.0.1",
         "markdown-it": "^14.3.0",
@@ -487,6 +488,15 @@
       "integrity": "sha512-cYQ9310grqxueWbl+WuIUIaiUaDcj7WOq5fVhEljNVgRfOUhY9fy2zTvfoqWsnebh8Sl70VScFbICvJnLKB0Og==",
       "license": "MIT"
     },
+    "node_modules/@lucide/vue": {
+      "version": "1.24.0",
+      "resolved": "https://registry.npmjs.org/@lucide/vue/-/vue-1.24.0.tgz",
+      "integrity": "sha512-5bNPX0G2YEWdUlBYk7pE8SgDg/f1mkIFpJ9vtE44pW/cwRz7Ioc0tOTESoVJAPvxIELSmYekX+XXIJMjsswNIg==",
+      "license": "ISC",
+      "peerDependencies": {
+        "vue": ">=3.0.1"
+      }
+    },
     "node_modules/@rolldown/pluginutils": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/@rolldown/pluginutils/-/pluginutils-1.0.1.tgz",
diff --git a/ai_knowledge_base_v2/apps/user-client/package.json b/ai_knowledge_base_v2/apps/user-client/package.json
index ac54eb3..b31500d 100644
--- a/ai_knowledge_base_v2/apps/user-client/package.json
+++ b/ai_knowledge_base_v2/apps/user-client/package.json
@@ -9,6 +9,7 @@
     "preview": "vite preview --host 127.0.0.1"
   },
   "dependencies": {
+    "@lucide/vue": "^1.24.0",
     "@types/markdown-it": "^14.1.2",
     "@vitejs/plugin-vue": "^6.0.1",
     "markdown-it": "^14.3.0",
diff --git a/ai_knowledge_base_v2/apps/user-client/src/App.vue b/ai_knowledge_base_v2/apps/user-client/src/App.vue
index 690f5e2..83464ca 100644
--- a/ai_knowledge_base_v2/apps/user-client/src/App.vue
+++ b/ai_knowledge_base_v2/apps/user-client/src/App.vue
@@ -178,7 +178,7 @@ async function scrollToBottom() {
 
 <template>
   <main class="app-shell">
-    <section class="phone-frame">
+    <section class="phone-frame" :class="{ 'login-mode': !user && !booting }">
       <div v-if="booting" class="booting">正在启动...</div>
       <LoginPanel v-else-if="!user" @logged-in="onLoggedIn" />
       <template v-else>
diff --git a/ai_knowledge_base_v2/apps/user-client/src/components/AppDialog.vue b/ai_knowledge_base_v2/apps/user-client/src/components/AppDialog.vue
new file mode 100644
index 0000000..a6de0b0
--- /dev/null
+++ b/ai_knowledge_base_v2/apps/user-client/src/components/AppDialog.vue
@@ -0,0 +1,25 @@
+<script setup lang="ts">
+import { X } from "@lucide/vue";
+
+defineProps<{
+  title: string;
+  labelledBy: string;
+}>();
+
+defineEmits<{ close: [] }>();
+</script>
+
+<template>
+  <div class="modal-backdrop" role="presentation" @click.self="$emit('close')">
+    <section class="app-dialog" role="dialog" aria-modal="true" :aria-labelledby="labelledBy">
+      <header class="dialog-header">
+        <h2 :id="labelledBy">{{ title }}</h2>
+        <button type="button" class="dialog-close" aria-label="关闭" @click="$emit('close')">
+          <X :size="20" aria-hidden="true" />
+        </button>
+      </header>
+      <div class="dialog-content"><slot /></div>
+      <footer v-if="$slots.footer" class="dialog-footer"><slot name="footer" /></footer>
+    </section>
+  </div>
+</template>
diff --git a/ai_knowledge_base_v2/apps/user-client/src/components/HelpDialog.vue b/ai_knowledge_base_v2/apps/user-client/src/components/HelpDialog.vue
new file mode 100644
index 0000000..e881bdf
--- /dev/null
+++ b/ai_knowledge_base_v2/apps/user-client/src/components/HelpDialog.vue
@@ -0,0 +1,31 @@
+<script setup lang="ts">
+import { CircleCheck } from "@lucide/vue";
+import AppDialog from "./AppDialog.vue";
+
+defineProps<{
+  mode: "sms" | "login";
+  contact?: string;
+}>();
+
+defineEmits<{ close: [] }>();
+</script>
+
+<template>
+  <AppDialog
+    :title="mode === 'sms' ? '收不到验证码？' : '登录遇到问题'"
+    :labelled-by="mode === 'sms' ? 'sms-help-title' : 'login-help-title'"
+    @close="$emit('close')"
+  >
+    <ul class="help-list">
+      <li><CircleCheck :size="18" aria-hidden="true" /><span>确认输入的是后台登记的本人手机号。</span></li>
+      <li v-if="mode === 'sms'"><CircleCheck :size="18" aria-hidden="true" /><span>检查短信拦截、骚扰信息和手机信号。</span></li>
+      <li><CircleCheck :size="18" aria-hidden="true" /><span>等待倒计时结束后再重新发送，避免频繁操作。</span></li>
+      <li><CircleCheck :size="18" aria-hidden="true" /><span>网络异常时切换稳定网络后重试。</span></li>
+    </ul>
+    <p v-if="contact" class="support-contact">仍未解决，请联系工作人员：{{ contact }}</p>
+    <p v-else class="support-contact">仍未解决，请联系大本营工作人员核对学员信息。</p>
+    <template #footer>
+      <button type="button" class="dialog-confirm" @click="$emit('close')">知道了</button>
+    </template>
+  </AppDialog>
+</template>
diff --git a/ai_knowledge_base_v2/apps/user-client/src/components/LoginPanel.vue b/ai_knowledge_base_v2/apps/user-client/src/components/LoginPanel.vue
index 47c9eec..886ced8 100644
--- a/ai_knowledge_base_v2/apps/user-client/src/components/LoginPanel.vue
+++ b/ai_knowledge_base_v2/apps/user-client/src/components/LoginPanel.vue
@@ -1,145 +1,355 @@
 <script setup lang="ts">
-import { onMounted, onUnmounted, ref } from "vue";
-import { api, saveToken } from "../services/api";
+import {
+  CircleHelp,
+  GraduationCap,
+  RefreshCw,
+  ShieldCheck,
+  Smartphone,
+  X,
+} from "@lucide/vue";
+import { computed, nextTick, onMounted, onUnmounted, ref, watch } from "vue";
+
+import { api, ApiError, saveToken } from "../services/api";
 import type { UserProfile } from "../types/api";
+import AppDialog from "./AppDialog.vue";
+import HelpDialog from "./HelpDialog.vue";
+import PolicyDialog from "./PolicyDialog.vue";
 
 const emit = defineEmits<{
   loggedIn: [user: UserProfile];
 }>();
 
+const COUNTDOWN_SECONDS = 60;
+const COUNTDOWN_PREFIX = "ai-kb-sms-countdown:";
+const PHONE_PATTERN = /^1[3-9]\d{9}$/;
+
 const phone = ref("");
 const code = ref("");
+const phoneTouched = ref(false);
+const sending = ref(false);
+const loggingIn = ref(false);
+const countdown = ref(0);
+const agreed = ref(false);
+const agreementAttention = ref(false);
+const activePolicy = ref<"agreement" | "privacy" | null>(null);
+const helpMode = ref<"sms" | "login" | null>(null);
+const toast = ref("");
+
+const captchaOpen = ref(false);
 const captchaId = ref("");
 const captchaCode = ref("");
 const captchaImage = ref("");
-const loading = ref(false);
 const captchaLoading = ref(false);
-const message = ref("请先完成图形验证码，再获取短信验证码。");
-const errorDialog = ref("");
-const countdown = ref(0);
-let countdownTimer: ReturnType<typeof setInterval> | null = null;
+const captchaSubmitting = ref(false);
+const captchaError = ref("");
 
-function startCountdown(seconds = 60) {
-  countdown.value = seconds;
-  if (countdownTimer) clearInterval(countdownTimer);
-  countdownTimer = setInterval(() => {
-    countdown.value--;
-    if (countdown.value <= 0 && countdownTimer) {
-      clearInterval(countdownTimer);
-      countdownTimer = null;
-    }
-  }, 1000);
+const supportContact = import.meta.env.VITE_SUPPORT_CONTACT?.trim() ?? "";
+const phoneValid = computed(() => PHONE_PATTERN.test(phone.value));
+const phoneError = computed(() => phoneTouched.value && phone.value.length > 0 && !phoneValid.value);
+const loginFieldsValid = computed(() => phoneValid.value && code.value.length >= 4);
+const sendButtonText = computed(() => {
+  if (sending.value) return "发送中...";
+  if (countdown.value > 0) return `${countdown.value}s 后重发`;
+  return "发送验证码";
+});
+
+let countdownTimer: ReturnType<typeof setInterval> | null = null;
+let toastTimer: ReturnType<typeof setTimeout> | null = null;
+
+onMounted(() => restoreCountdown());
+onUnmounted(() => {
+  stopCountdownTimer();
+  if (toastTimer) clearTimeout(toastTimer);
+});
+
+watch(phone, () => {
+  code.value = sanitizeDigits(code.value, 6);
+  restoreCountdown();
+});
+
+function onPhoneInput(event: Event) {
+  phone.value = sanitizeDigits((event.target as HTMLInputElement).value, 11);
 }
 
-onUnmounted(() => {
-  if (countdownTimer) clearInterval(countdownTimer);
-});
+function onCodeInput(event: Event) {
+  code.value = sanitizeDigits((event.target as HTMLInputElement).value, 6);
+}
 
-onMounted(() => {
-  void loadCaptcha();
-});
+function sanitizeDigits(value: string, maxLength: number) {
+  return value.replace(/\D/g, "").slice(0, maxLength);
+}
+
+function clearPhone() {
+  phone.value = "";
+  phoneTouched.value = false;
+}
+
+async function sendCode() {
+  if (sending.value || countdown.value > 0) return;
+  phoneTouched.value = true;
+  if (!phoneValid.value) {
+    showToast("请输入正确的手机号码");
+    return;
+  }
+
+  sending.value = true;
+  try {
+    await api.sendSms(phone.value);
+    completeSmsSend();
+  } catch (error) {
+    if (error instanceof ApiError && error.status === 428) {
+      await openCaptcha();
+    } else {
+      showToast(errorMessage(error, "验证码发送失败，请稍后重试"));
+    }
+  } finally {
+    sending.value = false;
+  }
+}
+
+async function openCaptcha() {
+  captchaOpen.value = true;
+  captchaError.value = "";
+  await loadCaptcha();
+}
 
 async function loadCaptcha() {
+  if (captchaLoading.value) return;
   captchaLoading.value = true;
+  captchaError.value = "";
   try {
     const result = await api.captcha();
     captchaId.value = result.captchaId;
     captchaImage.value = result.imageBase64;
     captchaCode.value = "";
   } catch (error) {
-    message.value = error instanceof Error ? error.message : "图形验证码加载失败";
+    captchaError.value = errorMessage(error, "图形验证码加载失败，请重试");
   } finally {
     captchaLoading.value = false;
   }
 }
 
-async function sendCode() {
-  if (!captchaId.value || captchaCode.value.length < 4) {
-    showError("请先输入图形验证码");
+async function submitCaptcha() {
+  if (captchaSubmitting.value) return;
+  const normalizedCode = captchaCode.value.trim();
+  if (normalizedCode.length < 4) {
+    captchaError.value = "请输入图形验证码";
     return;
   }
-  loading.value = true;
-  message.value = "";
+
+  captchaSubmitting.value = true;
+  captchaError.value = "";
   try {
-    await api.sendSms(phone.value, captchaId.value, captchaCode.value);
-    message.value = "短信验证码已发送，请查收。";
-    startCountdown(60);
-    await loadCaptcha();
+    await api.sendSms(phone.value, captchaId.value, normalizedCode);
+    captchaOpen.value = false;
+    completeSmsSend();
   } catch (error) {
-    showError(error instanceof Error ? error.message : "发送失败");
-    await loadCaptcha();
+    captchaError.value = errorMessage(error, "图形验证失败，请重试");
+    if (/图形验证码|过期/.test(captchaError.value)) await loadCaptcha();
   } finally {
-    loading.value = false;
+    captchaSubmitting.value = false;
   }
 }
 
+function completeSmsSend() {
+  persistCountdown(phone.value, Date.now() + COUNTDOWN_SECONDS * 1000);
+  restoreCountdown();
+  showToast("验证码已发送，请注意查收");
+}
+
 async function login() {
-  loading.value = true;
-  message.value = "";
+  if (loggingIn.value || !loginFieldsValid.value) return;
+  if (!agreed.value) {
+    agreementAttention.value = true;
+    showToast("请先阅读并同意用户协议和隐私政策");
+    window.setTimeout(() => (agreementAttention.value = false), 1800);
+    return;
+  }
+
+  loggingIn.value = true;
   try {
     const result = await api.login(phone.value, code.value);
     saveToken(result.token);
+    showToast("登录成功");
     emit("loggedIn", result.user);
   } catch (error) {
-    message.value = error instanceof Error ? error.message : "登录失败";
+    showToast(errorMessage(error, "登录失败，请稍后重试"));
   } finally {
-    loading.value = false;
+    loggingIn.value = false;
   }
 }
 
-function showError(text: string) {
-  message.value = text;
-  errorDialog.value = text;
+function countdownKey(value = phone.value) {
+  return `${COUNTDOWN_PREFIX}${value}`;
+}
+
+function persistCountdown(value: string, expiresAt: number) {
+  window.localStorage.setItem(countdownKey(value), String(expiresAt));
+}
+
+function restoreCountdown() {
+  stopCountdownTimer();
+  if (!phoneValid.value) {
+    countdown.value = 0;
+    return;
+  }
+  updateCountdown();
+  if (countdown.value > 0) countdownTimer = setInterval(updateCountdown, 1000);
+}
+
+function updateCountdown() {
+  const stored = Number(window.localStorage.getItem(countdownKey()) ?? 0);
+  const remaining = Math.max(0, Math.ceil((stored - Date.now()) / 1000));
+  countdown.value = remaining;
+  if (remaining <= 0) {
+    window.localStorage.removeItem(countdownKey());
+    stopCountdownTimer();
+  }
+}
+
+function stopCountdownTimer() {
+  if (countdownTimer) clearInterval(countdownTimer);
+  countdownTimer = null;
+}
+
+function showToast(text: string) {
+  toast.value = text;
+  if (toastTimer) clearTimeout(toastTimer);
+  toastTimer = setTimeout(() => (toast.value = ""), 3000);
+}
+
+function errorMessage(error: unknown, fallback: string) {
+  return error instanceof Error ? error.message : fallback;
+}
+
+async function keepFieldVisible(event: FocusEvent) {
+  await nextTick();
+  (event.target as HTMLElement).scrollIntoView({ block: "center", behavior: "smooth" });
 }
 </script>
 
 <template>
-  <section class="login-panel">
-    <h1>大本营答疑助手</h1>
-    <p>有问题随时问，帮你快速找到答案。</p>
+  <section class="login-page">
+    <div class="login-content">
+      <header class="login-brand-area">
+        <div class="brand-heading">
+          <span class="brand-icon" aria-hidden="true"><GraduationCap :size="30" stroke-width="2.2" /></span>
+          <h1>大本营答疑助手</h1>
+        </div>
+        <p>登录后即可开始提问，快速找到你需要的答案</p>
+        <ShieldCheck class="brand-watermark" :size="150" stroke-width="1.2" aria-hidden="true" />
+      </header>
 
-    <label>
-      手机号
-      <input v-model="phone" inputmode="numeric" maxlength="11" placeholder="请输入手机号" />
-    </label>
+      <form class="login-card" novalidate @submit.prevent="login">
+        <div class="form-field">
+          <label for="login-phone">手机号</label>
+          <div class="input-shell" :class="{ invalid: phoneError }">
+            <Smartphone :size="20" aria-hidden="true" />
+            <input
+              id="login-phone"
+              :value="phone"
+              type="tel"
+              inputmode="numeric"
+              autocomplete="tel"
+              maxlength="11"
+              placeholder="请输入手机号"
+              @input="onPhoneInput"
+              @blur="phoneTouched = true"
+              @focus="keepFieldVisible"
+            />
+            <button v-if="phone" type="button" class="input-clear" aria-label="清空手机号" @click="clearPhone">
+              <X :size="17" aria-hidden="true" />
+            </button>
+          </div>
+          <p v-if="phoneError" class="field-error">请输入正确的手机号码</p>
+        </div>
 
-    <label>
-      图形验证码
-      <div class="captcha-row">
-        <input v-model="captchaCode" inputmode="text" maxlength="8" placeholder="请输入图形验证码" />
-        <button type="button" class="captcha-image" :disabled="captchaLoading" @click="loadCaptcha">
-          <img v-if="captchaImage" :src="captchaImage" alt="图形验证码" />
-          <span v-else>{{ captchaLoading ? "加载中" : "刷新" }}</span>
+        <div class="form-field">
+          <label for="login-code">短信验证码</label>
+          <div class="input-shell code-input-shell">
+            <ShieldCheck :size="20" aria-hidden="true" />
+            <input
+              id="login-code"
+              :value="code"
+              type="text"
+              inputmode="numeric"
+              autocomplete="one-time-code"
+              maxlength="6"
+              placeholder="请输入短信验证码"
+              @input="onCodeInput"
+              @focus="keepFieldVisible"
+            />
+            <span class="input-divider" aria-hidden="true"></span>
+            <button
+              type="button"
+              class="send-code-button"
+              :disabled="!phoneValid || sending || countdown > 0"
+              @click="sendCode"
+            >
+              {{ sendButtonText }}
+            </button>
+          </div>
+          <p class="security-hint"><ShieldCheck :size="16" aria-hidden="true" />为保障账号安全，必要时将进行图形验证</p>
+        </div>
+
+        <div class="agreement-row" :class="{ attention: agreementAttention }">
+          <label class="agreement-toggle">
+            <input v-model="agreed" type="checkbox" />
+            <span>我已阅读并同意</span>
+          </label>
+          <button type="button" class="policy-link" @click="activePolicy = 'agreement'">《用户协议》</button>
+          <span aria-hidden="true">和</span>
+          <button type="button" class="policy-link" @click="activePolicy = 'privacy'">《隐私政策》</button>
+        </div>
+
+        <button type="submit" class="login-submit" :disabled="!loginFieldsValid || loggingIn">
+          {{ loggingIn ? "正在进入..." : "立即进入" }}
         </button>
-      </div>
-    </label>
 
-    <label>
-      短信验证码
-      <div class="code-row">
-        <input v-model="code" inputmode="numeric" maxlength="8" placeholder="请输入短信验证码" />
-        <button
-          type="button"
-          class="secondary"
-          :disabled="loading || countdown > 0 || phone.length < 11 || captchaCode.length < 4"
-          @click="sendCode"
-        >
-          {{ countdown > 0 ? `${countdown} 秒后重发` : "发送" }}
-        </button>
-      </div>
-    </label>
+        <div class="login-help-links">
+          <button type="button" @click="helpMode = 'sms'">收不到验证码？</button>
+          <span aria-hidden="true"></span>
+          <button type="button" @click="helpMode = 'login'">登录遇到问题</button>
+        </div>
+      </form>
 
-    <button type="button" class="primary" :disabled="loading || phone.length < 11 || code.length < 4" @click="login">
-      {{ loading ? "处理中..." : "立即进入" }}
-    </button>
-    <div class="form-tip">{{ message }}</div>
-
-    <div v-if="errorDialog" class="dialog-mask" role="alertdialog" aria-modal="true" aria-labelledby="login-error-title">
-      <div class="dialog-box">
-        <strong id="login-error-title">无法发送验证码</strong>
-        <p>{{ errorDialog }}</p>
-        <button type="button" class="primary" @click="errorDialog = ''">知道了</button>
-      </div>
+      <footer class="login-security-footer">
+        <span></span><ShieldCheck :size="20" aria-hidden="true" /><span></span>
+        <p>仅用于身份验证与账号登录，不会泄露你的信息</p>
+      </footer>
     </div>
+
+    <div v-if="toast" class="login-toast" role="status" aria-live="polite">{{ toast }}</div>
+
+    <AppDialog v-if="captchaOpen" title="安全验证" labelled-by="captcha-dialog-title" @close="captchaOpen = false">
+      <div class="captcha-dialog-copy">
+        <p>请完成图形验证后继续发送短信验证码。</p>
+        <div class="captcha-entry">
+          <input
+            v-model.trim="captchaCode"
+            type="text"
+            inputmode="text"
+            autocomplete="off"
+            maxlength="8"
+            placeholder="请输入图形验证码"
+            @keyup.enter="submitCaptcha"
+          />
+          <button type="button" :disabled="captchaLoading" aria-label="刷新图形验证码" @click="loadCaptcha">
+            <img v-if="captchaImage" :src="captchaImage" alt="图形验证码，点击刷新" />
+            <RefreshCw v-else :size="20" :class="{ spinning: captchaLoading }" aria-hidden="true" />
+          </button>
+        </div>
+        <p class="captcha-refresh-tip"><CircleHelp :size="15" aria-hidden="true" />看不清？点击图片刷新</p>
+        <p v-if="captchaError" class="field-error">{{ captchaError }}</p>
+      </div>
+      <template #footer>
+        <button type="button" class="dialog-confirm" :disabled="captchaSubmitting" @click="submitCaptcha">
+          {{ captchaSubmitting ? "验证中..." : "确认并发送" }}
+        </button>
+      </template>
+    </AppDialog>
+
+    <PolicyDialog v-if="activePolicy" :policy="activePolicy" @close="activePolicy = null" />
+    <HelpDialog v-if="helpMode" :mode="helpMode" :contact="supportContact" @close="helpMode = null" />
   </section>
 </template>
diff --git a/ai_knowledge_base_v2/apps/user-client/src/components/PolicyDialog.vue b/ai_knowledge_base_v2/apps/user-client/src/components/PolicyDialog.vue
new file mode 100644
index 0000000..9a8cca4
--- /dev/null
+++ b/ai_knowledge_base_v2/apps/user-client/src/components/PolicyDialog.vue
@@ -0,0 +1,40 @@
+<script setup lang="ts">
+import AppDialog from "./AppDialog.vue";
+
+defineProps<{ policy: "agreement" | "privacy" }>();
+defineEmits<{ close: [] }>();
+</script>
+
+<template>
+  <AppDialog
+    :title="policy === 'agreement' ? '用户协议' : '隐私政策'"
+    :labelled-by="policy === 'agreement' ? 'user-agreement-title' : 'privacy-policy-title'"
+    @close="$emit('close')"
+  >
+    <div v-if="policy === 'agreement'" class="policy-copy">
+      <p>欢迎使用大本营答疑助手。登录并使用本服务前，请阅读并理解本协议。</p>
+      <h3>一、服务说明</h3>
+      <p>本服务面向已登记学员提供知识问答。回答内容用于学习和信息参考，不替代专业意见。</p>
+      <h3>二、账号使用</h3>
+      <p>请使用本人登记手机号登录，不得转让账号、冒用他人身份或利用本服务进行违法违规活动。</p>
+      <h3>三、使用规范</h3>
+      <p>请勿提交违法、有害或侵犯他人权益的内容。为保障服务安全，系统可能记录必要的登录和问答日志。</p>
+      <h3>四、服务变更</h3>
+      <p>因维护、升级或不可抗力可能暂时中断服务，我们会在合理范围内尽快恢复。</p>
+    </div>
+    <div v-else class="policy-copy">
+      <p>我们重视你的个人信息安全，并按照最小必要原则处理登录和服务数据。</p>
+      <h3>一、收集的信息</h3>
+      <p>登录时处理手机号和验证码；使用过程中记录必要的会话、问答和安全审计信息。</p>
+      <h3>二、使用目的</h3>
+      <p>上述信息仅用于身份验证、账号登录、提供答疑服务、保障系统安全和排查服务问题。</p>
+      <h3>三、信息保护</h3>
+      <p>我们采取访问控制、传输保护、日志审计等措施保护信息，不会将验证码或登录凭证用于无关用途。</p>
+      <h3>四、你的权利</h3>
+      <p>如需查询、更正或处理账号信息，请通过工作人员提供的正式渠道联系我们。</p>
+    </div>
+    <template #footer>
+      <button type="button" class="dialog-confirm" @click="$emit('close')">我知道了</button>
+    </template>
+  </AppDialog>
+</template>
diff --git a/ai_knowledge_base_v2/apps/user-client/src/services/api.ts b/ai_knowledge_base_v2/apps/user-client/src/services/api.ts
index 7583734..73029c3 100644
--- a/ai_knowledge_base_v2/apps/user-client/src/services/api.ts
+++ b/ai_knowledge_base_v2/apps/user-client/src/services/api.ts
@@ -2,6 +2,18 @@ import type { ApiResponse, CaptchaResult, ChatMessage, ChatSession, LoginResult,
 
 const API_BASE = import.meta.env.VITE_API_BASE_URL ?? "/api";
 const TOKEN_KEY = "ai-kb-user-token";
+const REQUEST_TIMEOUT_MS = 15_000;
+
+export class ApiError extends Error {
+  constructor(
+    message: string,
+    readonly status: number,
+    readonly requestId = "",
+  ) {
+    super(message);
+    this.name = "ApiError";
+  }
+}
 
 export function getToken() {
   return window.localStorage.getItem(TOKEN_KEY);
@@ -22,18 +34,38 @@ async function request<T>(path: string, init: RequestInit = {}): Promise<T> {
   if (token) {
     headers.set("Authorization", `Bearer ${token}`);
   }
-  const response = await fetch(`${API_BASE}${path}`, { ...init, headers });
-  const body = (await response.json()) as ApiResponse<T>;
+  const controller = new AbortController();
+  const timeout = window.setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
+  let response: Response;
+  try {
+    response = await fetch(`${API_BASE}${path}`, { ...init, headers, signal: controller.signal });
+  } catch (error) {
+    if (error instanceof DOMException && error.name === "AbortError") {
+      throw new ApiError("请求超时，请检查网络后重试", 408);
+    }
+    throw new ApiError("网络连接失败，请稍后重试", 0);
+  } finally {
+    window.clearTimeout(timeout);
+  }
+
+  const body = (await response.json().catch(() => ({ code: response.status, message: "服务响应异常", data: null }))) as ApiResponse<T>;
   if (!response.ok || body.code !== 0) {
-    throw new Error(body.message || `${response.status} ${response.statusText}`);
+    throw new ApiError(
+      body.message || `${response.status} ${response.statusText}`,
+      response.status,
+      response.headers.get("X-Request-ID") ?? "",
+    );
   }
   return body.data;
 }
 
 export const api = {
   captcha: () => request<CaptchaResult>("/auth/captcha"),
-  sendSms: (phone: string, captchaId: string, captchaCode: string) =>
-    request<null>("/auth/sms/send", { method: "POST", body: JSON.stringify({ phone, captchaId, captchaCode }) }),
+  sendSms: (phone: string, captchaId?: string, captchaCode?: string) =>
+    request<null>("/auth/sms/send", {
+      method: "POST",
+      body: JSON.stringify({ phone, ...(captchaId && captchaCode ? { captchaId, captchaCode } : {}) }),
+    }),
   login: (phone: string, code: string) =>
     request<LoginResult>("/auth/login", { method: "POST", body: JSON.stringify({ phone, code }) }),
   logout: () => request<null>("/auth/logout", { method: "POST", body: JSON.stringify({}) }),
diff --git a/ai_knowledge_base_v2/apps/user-client/src/styles.css b/ai_knowledge_base_v2/apps/user-client/src/styles.css
index 39c2054..f2307bc 100644
--- a/ai_knowledge_base_v2/apps/user-client/src/styles.css
+++ b/ai_knowledge_base_v2/apps/user-client/src/styles.css
@@ -1,18 +1,36 @@
 :root {
-  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
-  color: #17211d;
-  background: #e9efed;
+  font-family: "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
+  color: #14221d;
+  background: #f6faf8;
   font-synthesis: none;
   text-rendering: optimizeLegibility;
+  --login-bg: #f6faf8;
+  --login-surface: #ffffff;
+  --login-text: #14221d;
+  --login-muted: #66756f;
+  --login-weak: #98a39f;
+  --login-brand: #42a982;
+  --login-brand-dark: #2f8f6d;
+  --login-border: #dce6e2;
+  --login-error: #d85b5b;
+  --login-disabled: #e8f0ed;
+  --login-radius-card: 22px;
+  --login-radius-control: 15px;
+  --login-shadow: 0 18px 54px rgba(35, 79, 63, 0.09);
 }
 
 * {
   box-sizing: border-box;
 }
 
+html {
+  background: var(--login-bg);
+}
+
 body {
   margin: 0;
   min-width: 320px;
+  overflow-x: hidden;
 }
 
 button,
@@ -25,16 +43,23 @@ button {
   cursor: pointer;
 }
 
+button:focus-visible,
+input:focus-visible,
+textarea:focus-visible {
+  outline: 3px solid rgba(66, 169, 130, 0.2);
+  outline-offset: 2px;
+}
+
 .app-shell {
   min-height: 100vh;
+  min-height: 100dvh;
   display: grid;
   place-items: center;
-  padding: 24px;
 }
 
 .phone-frame {
   position: relative;
-  width: min(100%, 430px);
+  width: min(calc(100% - 48px), 430px);
   height: min(860px, calc(100vh - 48px));
   min-height: 640px;
   overflow: hidden;
@@ -44,6 +69,19 @@ button {
   box-shadow: 0 28px 80px rgba(15, 31, 26, 0.18);
 }
 
+.phone-frame.login-mode {
+  width: 100%;
+  max-width: none;
+  height: auto;
+  min-height: 100vh;
+  min-height: 100dvh;
+  overflow: visible;
+  border: 0;
+  border-radius: 0;
+  background: var(--login-bg);
+  box-shadow: none;
+}
+
 .booting {
   height: 100%;
   display: grid;
@@ -51,167 +89,562 @@ button {
   color: #557066;
 }
 
-.login-panel {
-  height: 100%;
-  padding: 72px 24px 24px;
-  display: flex;
-  flex-direction: column;
-  gap: 18px;
-  background: linear-gradient(180deg, #ffffff 0%, #f3faf7 100%);
+.login-page {
+  min-height: 100vh;
+  min-height: 100dvh;
+  padding:
+    max(30px, env(safe-area-inset-top))
+    22px
+    max(24px, env(safe-area-inset-bottom));
+  background: var(--login-bg);
 }
 
-.brand-mark {
-  width: 56px;
-  height: 56px;
+.login-content {
+  width: min(100%, 460px);
+  min-height: calc(100vh - 54px);
+  min-height: calc(100dvh - 54px);
+  margin: 0 auto;
+  display: flex;
+  flex-direction: column;
+}
+
+.login-brand-area {
+  position: relative;
+  overflow: hidden;
+  padding: 28px 16px 26px;
+}
+
+.brand-heading {
+  position: relative;
+  z-index: 1;
+  display: flex;
+  align-items: center;
+  gap: 14px;
+}
+
+.brand-icon {
+  flex: 0 0 auto;
+  width: 54px;
+  height: 54px;
   display: grid;
   place-items: center;
   border-radius: 16px;
-  background: #0f8b6f;
+  background: var(--login-brand);
   color: #ffffff;
-  font-weight: 800;
+  box-shadow: 0 10px 24px rgba(47, 143, 109, 0.2);
+}
+
+.brand-heading h1 {
+  margin: 0;
+  color: var(--login-text);
+  font-size: 29px;
+  line-height: 1.25;
+  font-weight: 750;
   letter-spacing: 0;
 }
 
-.login-panel h1 {
-  margin: 10px 0 0;
-  font-size: 28px;
-  line-height: 1.2;
+.login-brand-area > p {
+  position: relative;
+  z-index: 1;
+  margin: 20px 0 0;
+  color: var(--login-muted);
+  font-size: 15px;
+  line-height: 1.7;
 }
 
-.login-panel p {
-  margin: 0 0 18px;
-  color: #5f746c;
+.brand-watermark {
+  position: absolute;
+  top: -28px;
+  right: -18px;
+  color: var(--login-brand);
+  opacity: 0.07;
+  pointer-events: none;
 }
 
-.login-panel label {
+.login-card {
   display: grid;
+  gap: 22px;
+  padding: 26px 24px 24px;
+  border: 1px solid rgba(220, 230, 226, 0.9);
+  border-radius: var(--login-radius-card);
+  background: rgba(255, 255, 255, 0.97);
+  box-shadow: var(--login-shadow);
+}
+
+.form-field {
+  display: grid;
+  gap: 10px;
+}
+
+.form-field > label {
+  color: var(--login-text);
+  font-size: 16px;
+  line-height: 1.4;
+  font-weight: 650;
+}
+
+.input-shell {
+  min-height: 54px;
+  display: flex;
+  align-items: center;
+  gap: 11px;
+  padding: 0 15px;
+  border: 1px solid var(--login-border);
+  border-radius: var(--login-radius-control);
+  background: var(--login-surface);
+  color: #a5b0ac;
+  transition: border-color 0.18s ease, box-shadow 0.18s ease;
+}
+
+.input-shell:focus-within {
+  border-color: var(--login-brand);
+  box-shadow: 0 0 0 3px rgba(66, 169, 130, 0.11);
+  color: var(--login-brand-dark);
+}
+
+.input-shell.invalid {
+  border-color: var(--login-error);
+}
+
+.input-shell input {
+  min-width: 0;
+  flex: 1;
+  height: 52px;
+  padding: 0;
+  border: 0;
+  outline: 0;
+  background: transparent;
+  color: var(--login-text);
+  font-size: 16px;
+  letter-spacing: 0;
+}
+
+.input-shell input::placeholder {
+  color: var(--login-weak);
+}
+
+.input-clear {
+  width: 44px;
+  height: 44px;
+  display: grid;
+  place-items: center;
+  margin-right: -12px;
+  border: 0;
+  background: transparent;
+  color: var(--login-weak);
+}
+
+.code-input-shell {
+  gap: 10px;
+  padding-right: 7px;
+}
+
+.input-divider {
+  width: 1px;
+  height: 26px;
+  background: var(--login-border);
+}
+
+.send-code-button {
+  min-width: 108px;
+  min-height: 44px;
+  padding: 0 8px;
+  border: 0;
+  background: transparent;
+  color: var(--login-brand-dark);
+  font-size: 15px;
+  font-weight: 650;
+  white-space: nowrap;
+}
+
+.send-code-button:disabled {
+  cursor: not-allowed;
+  color: var(--login-weak);
+}
+
+.security-hint {
+  min-height: 22px;
+  display: flex;
+  align-items: center;
+  gap: 7px;
+  margin: 0;
+  color: var(--login-weak);
+  font-size: 13px;
+  line-height: 1.6;
+}
+
+.field-error {
+  margin: -3px 0 0;
+  color: var(--login-error);
+  font-size: 13px;
+  line-height: 1.5;
+}
+
+.agreement-row {
+  min-height: 44px;
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 2px;
+  margin-top: 1px;
+  padding: 5px 4px;
+  border-radius: 10px;
+  color: var(--login-muted);
+  font-size: 13px;
+  line-height: 1.7;
+  transition: background 0.18s ease, color 0.18s ease;
+}
+
+.agreement-row.attention {
+  background: rgba(216, 91, 91, 0.08);
+  color: var(--login-error);
+}
+
+.agreement-toggle {
+  min-height: 34px;
+  display: inline-flex;
+  align-items: center;
   gap: 8px;
-  color: #40524b;
+  cursor: pointer;
+}
+
+.agreement-toggle input {
+  width: 20px;
+  height: 20px;
+  margin: 0;
+  accent-color: var(--login-brand-dark);
+  cursor: pointer;
+}
+
+.policy-link {
+  min-height: 34px;
+  padding: 0 2px;
+  border: 0;
+  background: transparent;
+  color: var(--login-brand-dark);
+  font-weight: 600;
+}
+
+.login-submit {
+  width: 100%;
+  height: 54px;
+  border: 0;
+  border-radius: 15px;
+  background: var(--login-brand-dark);
+  color: #ffffff;
+  font-size: 17px;
+  font-weight: 700;
+  letter-spacing: 0;
+  box-shadow: 0 11px 24px rgba(47, 143, 109, 0.2);
+  transition: transform 0.15s ease, background 0.15s ease;
+}
+
+.login-submit:not(:disabled):active {
+  transform: translateY(1px);
+  background: #287d60;
+}
+
+.login-submit:disabled,
+.dialog-confirm:disabled {
+  cursor: not-allowed;
+  background: var(--login-disabled);
+  color: var(--login-weak);
+  box-shadow: none;
+}
+
+.login-help-links {
+  min-height: 44px;
+  display: grid;
+  grid-template-columns: 1fr 1px 1fr;
+  align-items: center;
+  gap: 12px;
+}
+
+.login-help-links span {
+  width: 1px;
+  height: 18px;
+  background: var(--login-border);
+}
+
+.login-help-links button {
+  min-height: 44px;
+  padding: 0;
+  border: 0;
+  background: transparent;
+  color: var(--login-muted);
   font-size: 14px;
 }
 
-.login-panel input,
-.composer textarea {
-  width: 100%;
-  border: 1px solid #cad8d2;
-  border-radius: 14px;
-  background: #ffffff;
-  color: #17211d;
-  outline: none;
+.login-security-footer {
+  margin-top: auto;
+  padding: 34px 10px 6px;
+  color: #a3afaa;
+  text-align: center;
 }
 
-.login-panel input {
-  height: 48px;
-  padding: 0 14px;
+.login-security-footer > span {
+  display: inline-block;
+  width: calc(50% - 28px);
+  height: 1px;
+  margin: 0 8px 5px;
+  background: var(--login-border);
 }
 
-.login-panel input:focus,
-.composer textarea:focus {
-  border-color: #0f8b6f;
-  box-shadow: 0 0 0 3px rgba(15, 139, 111, 0.12);
+.login-security-footer p {
+  margin: 10px 0 0;
+  font-size: 12px;
+  line-height: 1.6;
 }
 
-.code-row {
+.login-toast {
+  position: fixed;
+  z-index: 80;
+  left: 50%;
+  bottom: max(28px, calc(env(safe-area-inset-bottom) + 18px));
+  max-width: calc(100vw - 40px);
+  padding: 11px 16px;
+  border-radius: 10px;
+  background: rgba(20, 34, 29, 0.92);
+  color: #ffffff;
+  font-size: 14px;
+  line-height: 1.5;
+  text-align: center;
+  transform: translateX(-50%);
+  box-shadow: 0 10px 30px rgba(20, 34, 29, 0.18);
+}
+
+.modal-backdrop {
+  position: fixed;
+  inset: 0;
+  z-index: 70;
   display: grid;
-  grid-template-columns: minmax(0, 1fr) 92px;
-  gap: 10px;
+  place-items: center;
+  padding: 22px;
+  background: rgba(20, 34, 29, 0.38);
 }
 
-.captcha-row {
-  display: grid;
-  grid-template-columns: minmax(0, 1fr) 128px;
-  gap: 10px;
-}
-
-.captcha-image {
-  height: 48px;
-  padding: 0;
+.app-dialog {
+  width: min(100%, 390px);
+  max-height: min(78vh, 650px);
+  display: flex;
+  flex-direction: column;
   overflow: hidden;
-  border: 1px solid #cad8d2;
-  border-radius: 14px;
+  border: 1px solid rgba(220, 230, 226, 0.95);
+  border-radius: 20px;
   background: #ffffff;
+  box-shadow: 0 24px 70px rgba(20, 34, 29, 0.2);
 }
 
-.captcha-image img {
+.dialog-header {
+  min-height: 64px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 12px;
+  padding: 16px 18px 12px 22px;
+  border-bottom: 1px solid #edf2f0;
+}
+
+.dialog-header h2 {
+  margin: 0;
+  color: var(--login-text);
+  font-size: 19px;
+  line-height: 1.4;
+}
+
+.dialog-close {
+  width: 44px;
+  height: 44px;
+  display: grid;
+  place-items: center;
+  border: 0;
+  border-radius: 50%;
+  background: transparent;
+  color: var(--login-muted);
+}
+
+.dialog-content {
+  overflow-y: auto;
+  padding: 20px 22px;
+  overscroll-behavior: contain;
+}
+
+.dialog-footer {
+  padding: 12px 22px max(18px, env(safe-area-inset-bottom));
+  border-top: 1px solid #edf2f0;
+}
+
+.dialog-confirm {
+  width: 100%;
+  min-height: 48px;
+  border: 0;
+  border-radius: 13px;
+  background: var(--login-brand-dark);
+  color: #ffffff;
+  font-size: 16px;
+  font-weight: 650;
+}
+
+.policy-copy p {
+  margin: 0 0 16px;
+  color: var(--login-muted);
+  font-size: 14px;
+  line-height: 1.8;
+}
+
+.policy-copy h3 {
+  margin: 20px 0 8px;
+  color: var(--login-text);
+  font-size: 15px;
+}
+
+.help-list {
+  display: grid;
+  gap: 15px;
+  margin: 0;
+  padding: 0;
+  list-style: none;
+}
+
+.help-list li {
+  display: grid;
+  grid-template-columns: 20px minmax(0, 1fr);
+  gap: 9px;
+  color: var(--login-muted);
+  font-size: 14px;
+  line-height: 1.7;
+}
+
+.help-list svg {
+  margin-top: 3px;
+  color: var(--login-brand-dark);
+}
+
+.support-contact {
+  margin: 20px 0 0;
+  padding: 12px 14px;
+  border-radius: 10px;
+  background: #f3f8f6;
+  color: #50645c;
+  font-size: 13px;
+  line-height: 1.7;
+}
+
+.captcha-dialog-copy > p:first-child {
+  margin: 0 0 15px;
+  color: var(--login-muted);
+  font-size: 14px;
+  line-height: 1.7;
+}
+
+.captcha-entry {
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) 132px;
+  gap: 10px;
+}
+
+.captcha-entry input {
+  min-width: 0;
+  height: 50px;
+  padding: 0 13px;
+  border: 1px solid var(--login-border);
+  border-radius: 13px;
+  outline: 0;
+  color: var(--login-text);
+  font-size: 16px;
+}
+
+.captcha-entry input:focus {
+  border-color: var(--login-brand);
+  box-shadow: 0 0 0 3px rgba(66, 169, 130, 0.11);
+}
+
+.captcha-entry button {
+  height: 50px;
+  display: grid;
+  place-items: center;
+  overflow: hidden;
+  padding: 0;
+  border: 1px solid var(--login-border);
+  border-radius: 13px;
+  background: #f8fbfa;
+  color: var(--login-brand-dark);
+}
+
+.captcha-entry img {
   width: 100%;
   height: 100%;
   display: block;
   object-fit: cover;
 }
 
-.captcha-image span {
-  color: #5f746c;
-  font-size: 13px;
+.captcha-refresh-tip {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  margin: 9px 0 0;
+  color: var(--login-weak);
+  font-size: 12px;
 }
 
-.primary,
-.secondary,
-.send-btn,
-.stop-btn,
-.new-session-btn {
-  border: 0;
-  border-radius: 14px;
-  font-weight: 700;
+.spinning {
+  animation: spin 0.8s linear infinite;
 }
 
-.primary {
-  height: 50px;
-  margin-top: 8px;
-  background: #0f8b6f;
-  color: #ffffff;
+@keyframes spin {
+  to { transform: rotate(360deg); }
 }
 
-.secondary {
-  background: #e5f3ef;
-  color: #0f735d;
+@media (max-width: 380px) {
+  .login-page {
+    padding-right: 18px;
+    padding-left: 18px;
+  }
+
+  .login-brand-area {
+    padding-right: 8px;
+    padding-left: 8px;
+  }
+
+  .brand-heading h1 {
+    font-size: 26px;
+  }
+
+  .login-card {
+    padding-right: 18px;
+    padding-left: 18px;
+  }
+
+  .send-code-button {
+    min-width: 96px;
+    font-size: 14px;
+  }
 }
 
-button:disabled {
-  cursor: not-allowed;
-  opacity: 0.52;
+@media (max-height: 700px) {
+  .login-page {
+    padding-top: max(16px, env(safe-area-inset-top));
+  }
+
+  .login-brand-area {
+    padding-top: 12px;
+    padding-bottom: 18px;
+  }
+
+  .login-card {
+    gap: 17px;
+  }
+
+  .login-security-footer {
+    padding-top: 22px;
+  }
 }
 
-.form-tip {
-  min-height: 20px;
-  color: #657970;
-  font-size: 13px;
-}
-
-.dialog-mask {
-  position: absolute;
-  inset: 0;
-  z-index: 20;
-  display: grid;
-  place-items: center;
-  padding: 24px;
-  background: rgba(12, 24, 20, 0.42);
-}
-
-.dialog-box {
-  width: min(100%, 320px);
-  padding: 22px;
-  border-radius: 18px;
-  background: #ffffff;
-  box-shadow: 0 18px 48px rgba(15, 31, 26, 0.22);
-}
-
-.dialog-box strong {
-  display: block;
-  color: #17211d;
-  font-size: 18px;
-  line-height: 1.35;
-}
-
-.dialog-box p {
-  margin: 10px 0 18px;
-  color: #51655d;
-  font-size: 14px;
-  line-height: 1.7;
-}
-
-.dialog-box .primary {
-  width: 100%;
-  margin-top: 0;
+@media (min-width: 700px) {
+  .login-page {
+    padding-top: 58px;
+    padding-bottom: 40px;
+  }
 }
 
 .topbar {