:root {
  --primary: #0b3d3a;
  --primary-light: #125e5a;
  --accent: #0284c7;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --success: #16a34a;
  --warning: #eab308;
  --danger: #dc2626;
  --radius: 8px;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }

body { background: var(--bg); color: var(--text); display: flex; min-height: 100vh; }

.sidebar { width: 260px; background: var(--primary); color: #fff; display: flex; flex-direction: column; flex-shrink: 0; }
.sidebar-head { padding: 20px; border-bottom: 1px solid rgba(255,255,255,0.1); }
.sidebar-head h2 { font-size: 16px; letter-spacing: 0.5px; }
.sidebar-head p { font-size: 12px; color: #94a3b8; margin-top: 4px; }

.nav-links { list-style: none; padding: 12px 0; flex: 1; overflow-y: auto; }
.nav-links li a { display: flex; align-items: center; gap: 12px; padding: 12px 20px; color: #cbd5e1; text-decoration: none; font-size: 14px; transition: background 0.2s; }
.nav-links li a:hover, .nav-links li.active a { background: var(--primary-light); color: #fff; font-weight: 600; }

.sidebar-foot { padding: 16px 20px; border-top: 1px solid rgba(255,255,255,0.1); font-size: 13px; color: #94a3b8; }
.sidebar-foot a { color: #f87171; text-decoration: none; display: block; margin-top: 6px; }

.main-content { flex: 1; display: flex; flex-direction: column; overflow-x: hidden; }

.topbar { height: 60px; background: #fff; border-bottom: 1px solid var(--border); display: flex; align-items: center; justify-content: space-between; padding: 0 24px; }
.topbar h1 { font-size: 18px; font-weight: 600; color: var(--primary); }
.user-badge { display: flex; align-items: center; gap: 10px; font-size: 14px; }
.avatar { width: 34px; height: 34px; border-radius: 50%; background: var(--primary-light); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: bold; }

.page-body { padding: 24px; flex: 1; }

.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 24px; }
.stat-card { background: #fff; padding: 20px; border-radius: var(--radius); border: 1px solid var(--border); box-shadow: 0 1px 3px rgba(0,0,0,0.05); }
.stat-card .label { font-size: 12px; font-weight: 600; text-transform: uppercase; color: var(--text-muted); }
.stat-card .val { font-size: 26px; font-weight: bold; color: var(--primary); margin-top: 6px; }

.card { background: #fff; border-radius: var(--radius); border: 1px solid var(--border); box-shadow: 0 1px 3px rgba(0,0,0,0.05); margin-bottom: 24px; }
.card-header { padding: 16px 20px; border-bottom: 1px solid var(--border); display: flex; align-items: center; justify-content: space-between; }
.card-header h2 { font-size: 16px; font-weight: 600; }
.card-body { padding: 20px; }

.table-responsive { width: 100%; overflow-x: auto; }
table { width: 100%; border-collapse: collapse; text-align: left; font-size: 14px; }
th, td { padding: 12px 16px; border-bottom: 1px solid var(--border); }
th { background: #f8fafc; font-weight: 600; color: var(--text-muted); font-size: 12px; text-transform: uppercase; }
tr:hover { background: #f1f5f9; }

.btn { display: inline-flex; align-items: center; gap: 6px; padding: 8px 16px; border-radius: 6px; font-size: 14px; font-weight: 500; text-decoration: none; border: none; cursor: pointer; transition: 0.2s; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-light); }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { background: #f8fafc; }
.btn-sm { padding: 4px 8px; font-size: 12px; }

.badge { display: inline-block; padding: 3px 8px; border-radius: 9999px; font-size: 12px; font-weight: 600; }
.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef9c3; color: #854d0e; }
.badge-danger { background: #fee2e2; color: #991b1b; }
.badge-info { background: #e0f2fe; color: #075985; }

.login-page { min-height: 100vh; width: 100%; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #0b3d3a 0%, #1e293b 100%); }
.login-box { width: 400px; background: #fff; padding: 36px; border-radius: 12px; box-shadow: 0 10px 25px rgba(0,0,0,0.2); }
.login-box h2 { color: var(--primary); margin-bottom: 6px; font-size: 22px; }
.login-box p { color: var(--text-muted); font-size: 14px; margin-bottom: 24px; }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 6px; color: var(--text); }
.form-control { width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 6px; font-size: 14px; }
.form-control:focus { outline: none; border-color: var(--primary); }

.alert { padding: 12px 16px; border-radius: 6px; margin-bottom: 16px; font-size: 14px; }
.alert-danger { background: #fee2e2; color: #991b1b; border: 1px solid #fecaca; }
.alert-warning { background: #fef9c3; color: #854d0e; border: 1px solid #fef08a; }
.alert-success { background: #dcfce7; color: #166534; border: 1px solid #bbf7d0; }