feat(frontend): Align admin and user API integration

frontend/video-frontend-admin/src/views/login/index.vue

@@ -4,6 +4,7 @@
       <div class="login-header">
         <h1 class="logo">HAOVP</h1>
         <p class="title">管理后台</p>
+        <p class="subtitle">统一管理平台用户、内容审核、评论治理与运营数据</p>
       </div>
 
       <el-form ref="loginFormRef" :model="loginForm" :rules="loginRules" class="login-form">
@@ -73,6 +74,12 @@
           </el-button>
         </el-form-item>
       </el-form>
+
+      <div class="demo-tips">
+        <span>管理员账号：admin</span>
+        <span>登录密码：不少于 6 位</span>
+        <span>验证码请按图形输入</span>
+      </div>
     </div>
   </div>
 </template>
@@ -160,15 +167,19 @@ onMounted(() => {
   display: flex;
   align-items: center;
   justify-content: center;
-  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+  background:
+    radial-gradient(circle at top left, rgba(19, 110, 255, 0.22), transparent 28%),
+    radial-gradient(circle at bottom right, rgba(26, 188, 156, 0.2), transparent 32%),
+    linear-gradient(135deg, #081224 0%, #11284a 48%, #0f766e 100%);
 }
 
 .login-box {
-  width: 400px;
-  padding: 40px;
-  background: #fff;
-  border-radius: 8px;
-  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
+  width: 440px;
+  padding: 42px 40px 28px;
+  background: rgba(255, 255, 255, 0.96);
+  border-radius: 24px;
+  box-shadow: 0 24px 80px rgba(5, 18, 39, 0.36);
+  backdrop-filter: blur(20px);
 }
 
 .login-header {
@@ -186,10 +197,17 @@ onMounted(() => {
   }
 
   .title {
-    color: #666;
+    color: #355070;
     font-size: 16px;
     margin-top: 8px;
   }
+
+  .subtitle {
+    margin-top: 10px;
+    color: #6b7280;
+    font-size: 13px;
+    line-height: 1.7;
+  }
 }
 
 .captcha-wrapper {
@@ -225,4 +243,16 @@ onMounted(() => {
     width: 100%;
   }
 }
+
+.demo-tips {
+  margin-top: 18px;
+  padding: 14px 16px;
+  border-radius: 16px;
+  background: linear-gradient(135deg, #eff6ff, #ecfeff);
+  color: #355070;
+  display: grid;
+  gap: 6px;
+  font-size: 12px;
+  border: 1px solid rgba(59, 130, 246, 0.12);
+}
 </style>