:root {
  --sidebar-width: 240px;
  --primary: #4e73df;
  --bg: #f5f7fb;
}
* { box-sizing: border-box; }
body { font-family: 'Segoe UI', system-ui, -apple-system, sans-serif; background: var(--bg); font-size: 14px; color: #333; }
#wrapper { min-height: 100vh; }
#sidebar {
  width: var(--sidebar-width);
  min-height: 100vh;
  background: linear-gradient(180deg, #2c3e50 0%, #1a252f 100%);
  color: #fff;
  transition: margin .25s ease;
  flex-shrink: 0;
}
#sidebar .sidebar-header { background: rgba(0,0,0,.15); }
#sidebar .nav-link {
  color: rgba(255,255,255,.85) !important;
  padding: .6rem .9rem;
  border-radius: .4rem;
  margin-bottom: 2px;
  font-size: .9rem;
  transition: all .15s;
}
#sidebar .nav-link:hover { background: rgba(255,255,255,.08); color: #fff !important; }
#sidebar .nav-link i { width: 22px; display: inline-block; }
#page-content { min-width: 0; flex: 1; display: flex; flex-direction: column; }
main { flex: 1; }
.card { border: 0; box-shadow: 0 1px 3px rgba(0,0,0,.06); border-radius: .5rem; }
.card-header { background: #fff; font-weight: 600; border-bottom: 1px solid #eee; padding: .85rem 1.1rem; }
.table thead th { font-size: .75rem; text-transform: uppercase; letter-spacing: .4px; color: #6c757d; background: #fafbfc; border-bottom: 2px solid #eee; }
.table td { vertical-align: middle; }
.badge { font-weight: 500; letter-spacing: .3px; }
.border-start.border-4 { border-width: 4px !important; }
h3 { font-weight: 600; color: #2c3e50; }
a { color: var(--primary); }
.btn { border-radius: .35rem; font-weight: 500; }
.form-control, .form-select { border-radius: .35rem; }
.dropdown-menu { border: 0; box-shadow: 0 4px 12px rgba(0,0,0,.1); border-radius: .5rem; }
@media (max-width: 767px) {
  #sidebar { position: fixed; z-index: 1030; margin-left: calc(-1 * var(--sidebar-width)); }
  #sidebar.show { margin-left: 0; box-shadow: 2px 0 10px rgba(0,0,0,.2); }
}
@media print {
  #sidebar, header.navbar, footer, .btn { display: none !important; }
  #page-content { margin: 0 !important; }
  .card { box-shadow: none; border: 1px solid #ddd; }
}