:root {
  --bg-body: #f8fafc;
  --bg-card: #ffffff;
  --bg-input: #ffffff;
  --border-color: #e2e8f0;
  --border-focus: #3b82f6;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --success: #10b981;
  --success-bg: #ecfdf5;
  --warning: #f59e0b;
  --warning-bg: #fffbeb;
  --danger: #ef4444;
  --danger-bg: #fef2f2;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --card-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.06), 0 1px 2px 0 rgba(0, 0, 0, 0.04);
  --header-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background-color: var(--bg-body);
  color: var(--text-main);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* Master Navigation Bar */
.admin-navbar {
  background: #ffffff;
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--header-shadow);
  padding: 12px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 1000;
}
.brand-logo {
  font-size: 17px;
  font-weight: 800;
  color: #0f172a;
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}
.brand-badge {
  background: #eff6ff;
  color: var(--primary);
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 6px;
  border: 1px solid #dbeafe;
}

.nav-menu { display: flex; align-items: center; gap: 8px; }
.nav-link {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  padding: 8px 14px;
  border-radius: 8px;
  transition: all 0.2s;
}
.nav-link:hover { color: var(--primary); background: #f1f5f9; }
.nav-link.active { color: var(--primary); background: #eff6ff; font-weight: 700; }
.nav-link.logout { color: var(--danger); background: var(--danger-bg); margin-left: 4px; }
.nav-link.logout:hover { background: #fee2e2; }

.mobile-menu-btn {
  display: none;
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 18px;
  cursor: pointer;
  color: #334155;
}

/* Layout Container */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 24px;
}

.page-header {
  margin-bottom: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.page-title { font-size: 22px; font-weight: 800; color: #0f172a; }
.page-subtitle { font-size: 13px; color: var(--text-muted); margin-top: 2px; }

/* Cards & Grids */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  padding: 24px;
  margin-bottom: 24px;
}

.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 24px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }

/* Stat Metric Cards */
.stat-card {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.stat-title { font-size: 12px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.5px; }
.stat-value { font-size: 26px; font-weight: 800; color: #0f172a; margin-top: 8px; }
.stat-sub { font-size: 12px; color: var(--text-muted); margin-top: 6px; }

/* Form Elements */
.form-group { margin-bottom: 18px; }
label { display: block; font-size: 13px; font-weight: 600; color: #334155; margin-bottom: 6px; }
input[type="text"], input[type="number"], select, textarea {
  width: 100%;
  padding: 11px 14px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: #0f172a;
  font-size: 14px;
  transition: border-color 0.15s, box-shadow 0.15s;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.file-input-wrapper {
  background: #f8fafc;
  border: 1px dashed #cbd5e1;
  border-radius: 8px;
  padding: 10px 14px;
}
.file-input-wrapper input[type="file"] { font-size: 12px; color: #475569; width: 100%; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s;
}
.btn-primary { background: var(--primary); color: #ffffff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-success { background: var(--success); color: #ffffff; }
.btn-danger { background: var(--danger); color: #ffffff; }
.btn-outline { background: #ffffff; border-color: var(--border-color); color: #334155; }
.btn-outline:hover { background: #f1f5f9; }

/* Tables */
.table-responsive { width: 100%; overflow-x: auto; }
table { width: 100%; border-collapse: collapse; text-align: left; font-size: 13px; }
th { background: #f8fafc; color: #475569; font-weight: 700; padding: 12px 16px; border-bottom: 1px solid var(--border-color); }
td { padding: 14px 16px; border-bottom: 1px solid var(--border-color); color: #1e293b; }
tr:hover { background: #f8fafc; }

/* Badges */
.badge { display: inline-block; padding: 3px 8px; border-radius: 6px; font-size: 11px; font-weight: 700; text-transform: uppercase; }
.badge-pending { background: var(--warning-bg); color: #b45309; border: 1px solid #fde68a; }
.badge-active { background: var(--success-bg); color: #065f46; border: 1px solid #a7f3d0; }
.badge-danger { background: var(--danger-bg); color: #991b1b; border: 1px solid #fecaca; }

/* Mobile View Adjustments */
@media (max-width: 768px) {
  .mobile-menu-btn { display: block; }
  .nav-menu {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 59px;
    left: 0;
    width: 100%;
    background: #ffffff;
    border-bottom: 1px solid var(--border-color);
    padding: 16px 20px;
    box-shadow: 0 10px 15px -3px rgba(0,0,0,0.05);
    gap: 8px;
  }
  .nav-menu.show { display: flex; }
  .nav-link { width: 100%; text-align: left; padding: 10px 14px; }
  
  .grid-4 { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .grid-2 { grid-template-columns: 1fr; gap: 16px; }
  .container { padding: 16px; }
  .card { padding: 16px; }
}