:root {
  --bg: #0a0a18;
  --bg-soft: #12102a;
  --surface: #17133a;
  --surface-2: #1c1c3c;
  --border: rgba(255, 255, 255, 0.08);
  --text: #f3f1ff;
  --muted: #9e9cc4;
  --violet: #7c5cff;
  --violet-soft: #a78bfa;
  --indigo: #5b3fe8;
  --azure: #3b82f6;
  --mint: #14b8a6;
  --rose: #f43f5e;
  --gold: #f59e0b;
  --radius: 18px;
  --sidebar-w: 260px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background:
    radial-gradient(900px 420px at 10% -10%, rgba(124, 92, 255, 0.22), transparent 60%),
    radial-gradient(700px 360px at 100% 0%, rgba(59, 130, 246, 0.14), transparent 55%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
}

a { color: var(--violet-soft); text-decoration: none; }
a:hover { color: #c4b5fd; }

.app-shell {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  width: var(--sidebar-w);
  background: linear-gradient(180deg, #15122e 0%, #0f0d22 100%);
  border-right: 1px solid var(--border);
  padding: 1.25rem 1rem;
  position: sticky;
  top: 0;
  height: 100vh;
  z-index: 100;
}

.sidebar-brand {
  display: flex;
  gap: .85rem;
  align-items: center;
  padding: .5rem .65rem 1.25rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1rem;
}

.sidebar-brand strong {
  display: block;
  font-size: 1.05rem;
}

.sidebar-brand small {
  color: var(--muted);
}

.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--violet), var(--indigo));
  box-shadow: 0 10px 24px rgba(124, 92, 255, 0.35);
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: .35rem;
}

.sidebar-nav a {
  display: flex;
  align-items: center;
  gap: .7rem;
  padding: .75rem .9rem;
  border-radius: 12px;
  color: var(--muted);
  font-weight: 600;
  font-size: .92rem;
}

.sidebar-nav a i { font-size: 1.05rem; }

.sidebar-nav a:hover,
.sidebar-nav a.active {
  background: rgba(124, 92, 255, 0.14);
  color: #fff;
}

.sidebar-nav a.active {
  border: 1px solid rgba(124, 92, 255, 0.35);
}

.logout-link {
  margin-top: 1rem !important;
  color: #fda4af !important;
}

.main-wrap {
  flex: 1;
  min-width: 0;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: rgba(10, 10, 24, 0.65);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 50;
}

.topbar h1 {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 700;
}

.topbar-user {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: .75rem;
  color: var(--muted);
  font-size: .9rem;
}

.avatar {
  width: 36px;
  height: 36px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: rgba(124, 92, 255, 0.2);
  color: #fff;
  font-weight: 700;
}

.content {
  padding: 1.5rem;
}

.stat-card,
.panel-card {
  background: linear-gradient(180deg, rgba(28, 28, 60, 0.95), rgba(19, 19, 43, 0.95));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.22);
}

.stat-card {
  padding: 1.2rem 1.25rem;
  height: 100%;
}

.stat-card .label {
  color: var(--muted);
  font-size: .85rem;
  font-weight: 600;
}

.stat-card .value {
  font-size: 1.9rem;
  font-weight: 800;
  margin-top: .35rem;
}

.stat-card .icon {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: rgba(124, 92, 255, 0.16);
  color: var(--violet-soft);
}

.panel-card {
  padding: 1.25rem;
}

.panel-card h2,
.panel-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.table {
  --bs-table-bg: transparent;
  --bs-table-color: var(--text);
  --bs-table-border-color: var(--border);
  --bs-table-striped-bg: rgba(255, 255, 255, 0.02);
  --bs-table-hover-bg: rgba(124, 92, 255, 0.08);
  color: var(--text);
}

.table thead th {
  color: var(--muted);
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .04em;
  font-weight: 700;
  border-bottom-width: 1px;
}

.form-control,
.form-select {
  background: #12102a;
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 12px;
  min-height: 44px;
}

.form-control:focus,
.form-select:focus {
  background: #15132e;
  border-color: rgba(124, 92, 255, 0.55);
  color: var(--text);
  box-shadow: 0 0 0 .25rem rgba(124, 92, 255, 0.18);
}

.form-label {
  color: var(--muted);
  font-weight: 600;
  font-size: .85rem;
}

.btn-primary {
  --bs-btn-bg: var(--violet);
  --bs-btn-border-color: var(--violet);
  --bs-btn-hover-bg: #6b4eff;
  --bs-btn-hover-border-color: #6b4eff;
  --bs-btn-active-bg: var(--indigo);
  --bs-btn-active-border-color: var(--indigo);
  border-radius: 12px;
  font-weight: 700;
}

.btn-outline-light {
  border-radius: 12px;
  border-color: var(--border);
  color: var(--text);
}

.btn-outline-danger {
  border-radius: 12px;
}

.badge-soft {
  border-radius: 999px;
  padding: .35rem .7rem;
  font-weight: 700;
  font-size: .75rem;
}

.badge-active { background: rgba(20, 184, 166, 0.16); color: #5eead4; }
.badge-passive { background: rgba(244, 63, 94, 0.16); color: #fda4af; }
.badge-easy { background: rgba(20, 184, 166, 0.16); color: #5eead4; }
.badge-medium { background: rgba(245, 158, 11, 0.16); color: #fcd34d; }
.badge-hard { background: rgba(244, 63, 94, 0.16); color: #fda4af; }
.badge-exam { background: rgba(124, 92, 255, 0.16); color: var(--violet-soft); }

.login-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 1.5rem;
}

.login-card {
  width: 100%;
  max-width: 440px;
  background: linear-gradient(180deg, #1a1638, #12102a);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 2rem;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
}

.login-card h1 {
  font-size: 1.5rem;
  font-weight: 800;
}

.login-card p {
  color: var(--muted);
}

.modal-content {
  background: #17133a;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.modal-header,
.modal-footer {
  border-color: var(--border);
}

.form-check-input:checked {
  background-color: var(--violet);
  border-color: var(--violet);
}

.filter-bar {
  display: grid;
  gap: .75rem;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  margin-bottom: 1rem;
}

@media (max-width: 991.98px) {
  .sidebar {
    position: fixed;
    left: 0;
    transform: translateX(-105%);
    transition: transform .2s ease;
  }
  .sidebar.open { transform: translateX(0); }
  .content { padding: 1rem; }
}