:root {
  --bg: #f5f6fa; --card: #fff; --primary: #4f6ef7; --primary-dark: #3a57d4;
  --text: #2c3e50; --text-light: #7f8c8d; --border: #e8e9ef; --danger: #e74c3c; --success: #27ae60; --warn: #f39c12;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; background: var(--bg); color: var(--text); font-size: 14px; }
a { color: var(--primary); text-decoration: none; }

/* Layout */
.app { display: flex; min-height: 100vh; }
.sidebar { width: 220px; background: #1e2a3a; color: #cbd5e1; display: flex; flex-direction: column; position: fixed; height: 100vh; }
.logo { padding: 20px; font-size: 18px; font-weight: 700; color: #fff; border-bottom: 1px solid #2d3a4f; }
.sidebar nav { flex: 1; padding: 12px 0; }
.nav-item { display: flex; align-items: center; gap: 10px; padding: 12px 20px; color: #cbd5e1; transition: all .15s; }
.nav-item:hover { background: #2d3a4f; color: #fff; }
.nav-item.active { background: var(--primary); color: #fff; }
.nav-item .icon { font-size: 16px; }
.sidebar-footer { padding: 16px 20px; border-top: 1px solid #2d3a4f; font-size: 12px; display: flex; justify-content: space-between; align-items: center; }
.logout { color: #e74c3c; }

.main { flex: 1; margin-left: 220px; }
.topbar { background: var(--card); padding: 16px 24px; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; position: sticky; top: 0; z-index: 10; }
.topbar h1 { font-size: 18px; }
.user-info { color: var(--text-light); font-size: 13px; }
.content { padding: 24px; }

/* Cards */
.card { background: var(--card); border-radius: 8px; padding: 20px; margin-bottom: 16px; box-shadow: 0 1px 3px rgba(0,0,0,.05); }
.card-title { font-size: 16px; font-weight: 600; margin-bottom: 16px; padding-bottom: 12px; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }

/* Stat grid */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 16px; }
.stat-card { background: var(--card); border-radius: 8px; padding: 20px; box-shadow: 0 1px 3px rgba(0,0,0,.05); }
.stat-card .label { color: var(--text-light); font-size: 13px; margin-bottom: 8px; }
.stat-card .value { font-size: 28px; font-weight: 700; }
.stat-card .trend { font-size: 12px; margin-top: 6px; }
.stat-card .trend.up { color: var(--success); }
.stat-card .trend.down { color: var(--danger); }

/* Table */
table { width: 100%; border-collapse: collapse; font-size: 13px; }
th, td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--border); }
th { background: #f8f9fc; color: var(--text-light); font-weight: 600; font-size: 12px; text-transform: uppercase; letter-spacing: .5px; }
tr:hover { background: #f8f9fc; }
.tag { display: inline-block; padding: 2px 8px; border-radius: 4px; font-size: 12px; font-weight: 500; }
.tag-green { background: #d4edda; color: #155724; }
.tag-red { background: #f8d7da; color: #721c24; }
.tag-yellow { background: #fff3cd; color: #856404; }
.tag-blue { background: #d1ecf1; color: #0c5460; }
.tag-gray { background: #e2e3e5; color: #383d41; }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 6px; padding: 8px 16px; border: none; border-radius: 6px; cursor: pointer; font-size: 13px; font-weight: 500; transition: all .15s; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-warn { background: var(--warn); color: #fff; }
.btn-outline { background: #fff; color: var(--primary); border: 1px solid var(--primary); }
.btn-sm { padding: 4px 10px; font-size: 12px; }

/* Forms */
.form-row { margin-bottom: 14px; }
.form-row label { display: block; margin-bottom: 6px; color: var(--text-light); font-size: 13px; }
.form-row input, .form-row select, .form-row textarea { width: 100%; padding: 8px 12px; border: 1px solid var(--border); border-radius: 6px; font-size: 14px; font-family: inherit; }
.form-row input:focus, .form-row select:focus, .form-row textarea:focus { outline: none; border-color: var(--primary); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* Login */
.login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #1e2a3a 0%, #3a57d4 100%); }
.login-box { background: #fff; border-radius: 12px; padding: 40px; width: 380px; box-shadow: 0 20px 60px rgba(0,0,0,.3); }
.login-box h1 { text-align: center; margin-bottom: 8px; color: var(--text); }
.login-box .sub { text-align: center; color: var(--text-light); margin-bottom: 28px; font-size: 13px; }
.login-box .btn { width: 100%; justify-content: center; padding: 12px; }
.login-err { background: #f8d7da; color: #721c24; padding: 10px; border-radius: 6px; margin-bottom: 16px; font-size: 13px; text-align: center; }

/* Tabs */
.tabs { display: flex; gap: 4px; margin-bottom: 16px; border-bottom: 2px solid var(--border); }
.tab { padding: 10px 18px; cursor: pointer; border-bottom: 2px solid transparent; margin-bottom: -2px; color: var(--text-light); }
.tab.active { color: var(--primary); border-bottom-color: var(--primary); font-weight: 600; }
.tab:hover { color: var(--primary); }

/* Modal */
.modal-mask { position: fixed; inset: 0; background: rgba(0,0,0,.5); display: none; align-items: center; justify-content: center; z-index: 100; }
.modal-mask.show { display: flex; }
.modal { background: #fff; border-radius: 10px; padding: 24px; width: 560px; max-width: 90vw; max-height: 85vh; overflow-y: auto; }
.modal h3 { margin-bottom: 16px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 20px; }

/* Alert */
.alert { padding: 12px 16px; border-radius: 6px; margin-bottom: 16px; font-size: 13px; }
.alert-success { background: #d4edda; color: #155724; }
.alert-danger { background: #f8d7da; color: #721c24; }

/* Utility */
.text-right { text-align: right; }
.text-center { text-align: center; }
.mt-1 { margin-top: 8px; } .mt-2 { margin-top: 16px; }
.mb-1 { margin-bottom: 8px; } .mb-2 { margin-bottom: 16px; }
.flex { display: flex; } .flex-between { display: flex; justify-content: space-between; align-items: center; }
.gap-2 { gap: 12px; }
.mono { font-family: monospace; }

/* Badge counts */
.badge { background: var(--danger); color: #fff; border-radius: 10px; padding: 1px 6px; font-size: 11px; margin-left: 6px; }