优化中控科技风界面：登录居中、浮盈配色、默认打开首个客户端。

总览改名期权持仓总览，内容区 1800 居中，去掉左上角仓库名。

Co-authored-by: Cursor <cursoragent@cursor.com>

templates/login.html

@@ -1,13 +1,19 @@
 {% extends "base.html" %}
 {% block title %}登录 · 期权中控{% endblock %}
 {% block body %}
-<section class="login-card">
-  <h1>期权中控登录</h1>
-  <p class="muted">关联客户端仓库 crypto_okx · 本仓不下单</p>
-  <form method="post" class="stack">
-    <label>用户名 <input name="username" autocomplete="username" required></label>
-    <label>密码 <input type="password" name="password" autocomplete="current-password" required></label>
-    <button type="submit">登录</button>
-  </form>
-</section>
+<div class="login-wrap">
+  <section class="login-card">
+    <h1>期权中控</h1>
+    <p class="login-sub">多机期权持仓总览 · 内嵌打开客户端 · 本仓不下单</p>
+    <form method="post" class="stack" autocomplete="on">
+      <label>用户名
+        <input name="username" autocomplete="username" required placeholder="admin">
+      </label>
+      <label>密码
+        <input type="password" name="password" autocomplete="current-password" required placeholder="••••••••">
+      </label>
+      <button type="submit">登 录</button>
+    </form>
+  </section>
+</div>
 {% endblock %}