feat: 实现 Admin 首次初始化与网页登录 (#50)

admin/static/css/app.css

@@ -38,6 +38,40 @@ body {
 }
 .nav a:hover { background: #3a4552; color: #fff; }
 .nav a.active { background: #1f6feb; color: #fff; }
+.nav-user {
+  margin-left: auto;
+  color: #fff;
+  padding: 0 8px;
+}
+.nav-logout { margin: 0; }
+.nav-logout button {
+  color: #c8cdd4;
+  border-color: #56616d;
+  background: transparent;
+}
+.nav-logout button:hover { color: #fff; background: #3a4552; }
+
+/* ── 首次初始化 / 登录 ────────────────── */
+.auth-page {
+  min-height: 100vh;
+  display: grid;
+  place-items: center;
+  padding: 24px 16px;
+}
+.auth-card {
+  width: 100%;
+  max-width: 420px;
+  padding: 24px;
+  background: #fff;
+  border: 1px solid #e1e4e8;
+  border-radius: 6px;
+  box-shadow: 0 8px 24px rgba(0, 0, 0, .08);
+}
+.auth-card h1 { margin: 0 0 8px; font-size: 22px; }
+.auth-card form { display: grid; gap: 16px; margin-top: 20px; }
+.auth-card input { width: 100%; }
+.auth-card small { color: #777; }
+.auth-submit { width: 100%; min-height: 38px; }
 
 /* ── 页面主体 ─────────────────────────── */
 .page { padding: 16px; }
@@ -259,7 +293,7 @@ button.primary:hover { background: #1a5fd0; }
 /* 创建弹窗里的单个字段，标签在输入框上面 */
 .field { display: flex; flex-direction: column; gap: 6px; }
 .field label { color: #555; }
-input[type="text"] {
+input[type="text"], input[type="password"] {
   padding: 5px 8px;
   border: 1px solid #ccd1d6;
   border-radius: 3px;