/* ============================================================
   后台样式：科技蓝色板（与 CORE_SPEC 第9节一致）
   ============================================================ */
:root{
  --primary:#1668FF;
  --primary-dark:#0A5CFF;
  --primary-deep:#0B4FD8;
  --primary-light:#E8F0FF;
  --primary-lighter:#F5F8FF;
  --nav-bg:#0B1F3A;
  --nav-text:#FFFFFF;
  --bg:#FFFFFF;
  --bg-gray:#F5F8FF;
  --gradient:linear-gradient(135deg,#1668FF 0%,#4D9FFF 100%);
  --text:#1F2937;
  --text-2:#64748B;
  --border:#E2E8F0;
  --success:#10B981;
  --warning:#F59E0B;
  --danger:#EF4444;
  --radius:8px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:"Microsoft YaHei","PingFang SC",sans-serif;background:var(--bg-gray);color:var(--text);font-size:14px;line-height:1.6}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--primary-deep)}

/* 顶部 header */
.admin-header{
  height:56px;background:var(--nav-bg);color:var(--nav-text);
  display:flex;align-items:center;justify-content:space-between;padding:0 20px;
  position:sticky;top:0;z-index:100;
}
.logo{display:flex;align-items:center;gap:10px}
.logo-mark{background:var(--gradient);padding:4px 10px;border-radius:4px;font-weight:700;letter-spacing:1px}
.logo-text{font-size:15px}
.top-nav{display:flex;align-items:center;gap:14px}
.user-info{color:#cbd5e1;font-size:13px}
.user-info strong{color:#fff}

/* 主体布局 */
.admin-body{display:flex;min-height:calc(100vh - 56px - 36px)}
.admin-sidebar{
  width:220px;background:var(--nav-bg);color:#cbd5e1;
  padding:16px 0;overflow-y:auto;flex-shrink:0;
}
.side-group{margin-bottom:8px}
.side-group-title{
  font-size:12px;color:#7e8aa3;padding:8px 18px;letter-spacing:1px;
  text-transform:uppercase;
}
.side-menu{list-style:none}
.side-menu a{
  display:block;padding:8px 18px;color:#cbd5e1;font-size:13px;
  border-left:3px solid transparent;
}
.side-menu a:hover{background:rgba(22,104,255,.15);color:#fff;border-left-color:var(--primary)}
.admin-main{flex:1;padding:20px;background:var(--bg);overflow-x:auto}

/* 卡片 / 表格 / 按钮 */
.card{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:16px;margin-bottom:16px}
.card h2{font-size:16px;margin-bottom:12px;color:var(--text)}
table.grid{width:100%;border-collapse:collapse}
table.grid th,table.grid td{padding:8px 10px;border-bottom:1px solid var(--border);text-align:left;font-size:13px}
table.grid th{background:var(--primary-lighter);color:var(--text-2);font-weight:600}
.btn{
  display:inline-block;padding:6px 14px;border-radius:var(--radius);
  background:var(--gradient);color:#fff;border:none;cursor:pointer;font-size:13px;
}
.btn:hover{opacity:.9;color:#fff}
.btn-ghost{background:transparent;border:1px solid #3b4a6b;color:#cbd5e1}
.btn-ghost:hover{background:rgba(255,255,255,.1);color:#fff}
.btn-danger{background:var(--danger)}
.btn-sm{padding:3px 10px;font-size:12px}
.form-row{margin-bottom:12px}
.form-row label{display:block;margin-bottom:4px;color:var(--text-2);font-size:13px}
.form-row input,.form-row select,.form-row textarea{
  width:100%;padding:8px 10px;border:1px solid var(--border);border-radius:var(--radius);font-size:13px;
}
.form-row input:focus,.form-row select:focus{outline:none;border-color:var(--primary)}

/* 分页 */
.paging{margin-top:14px;display:flex;gap:6px;flex-wrap:wrap;align-items:center}
.paging a,.paging span{
  padding:4px 10px;border:1px solid var(--border);border-radius:4px;font-size:12px;
}
.paging .current{background:var(--primary);color:#fff;border-color:var(--primary)}
.paging .disabled{color:var(--text-2);background:var(--bg-gray)}
.paging .total{margin-left:10px;color:var(--text-2)}

/* 统计卡片 */
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-bottom:16px}
.stat-card{background:var(--gradient);color:#fff;padding:16px;border-radius:var(--radius)}
.stat-card .num{font-size:24px;font-weight:700}
.stat-card .label{opacity:.85;font-size:12px}

/* 登录页 */
.login-body{
  background:linear-gradient(135deg,#0B1F3A 0%,#1668FF 100%);
  min-height:100vh;display:flex;align-items:center;justify-content:center;
}
.login-box{
  background:#fff;padding:36px 40px;border-radius:var(--radius);
  width:380px;box-shadow:0 20px 60px rgba(0,0,0,.3);
}
.login-box h1{font-size:20px;margin-bottom:6px;color:var(--nav-bg)}
.login-box .sub{color:var(--text-2);margin-bottom:20px;font-size:13px}
.login-box .captcha-row{display:flex;gap:10px;align-items:center}
.login-box .captcha-box{
  background:var(--primary-lighter);padding:8px 14px;border-radius:var(--radius);
  font-weight:700;color:var(--primary-deep);letter-spacing:2px;min-width:80px;text-align:center;
}
.login-box .error{background:#fef2f2;color:var(--danger);padding:8px 12px;border-radius:var(--radius);margin-bottom:12px;font-size:13px}
.admin-footer{
  height:36px;text-align:center;color:var(--text-2);font-size:12px;
  background:#fff;border-top:1px solid var(--border);line-height:36px;
}

/* 响应式 */
@media (max-width:900px){
  .admin-body{flex-direction:column}
  .admin-sidebar{width:100%;display:flex;flex-wrap:wrap;padding:8px}
  .side-group{margin-right:10px}
  .stat-grid{grid-template-columns:repeat(2,1fr)}
}