/* =========================================================================
   Nova LMS — Design System
   Dark-blue, rounded-card aesthetic inspired by Coursera / Udemy / LinkedIn
   Learning. Centralized as CSS custom properties so the whole palette can
   be retuned from one place.
   ========================================================================= */

:root {
  --navy-950: #0a1128;
  --navy-900: #0f1b3d;
  --navy-800: #142452;
  --navy-700: #1b2f66;
  --navy-600: #24408a;
  --blue-500: #2f5be0;
  --blue-400: #4f7cf3;
  --accent-cyan: #22d3ee;
  --accent-amber: #f59e0b;
  --accent-green: #22c55e;
  --accent-red: #ef4444;

  --surface: #f4f6fb;
  --surface-card: #ffffff;
  --surface-muted: #eef1f8;
  --border-soft: #e3e8f4;

  --text-primary: #101a35;
  --text-secondary: #5a6584;
  --text-muted: #8992ac;

  --radius-lg: 1rem;
  --radius-md: 0.75rem;
  --radius-sm: 0.5rem;

  --shadow-soft: 0 4px 20px rgba(15, 27, 61, 0.06);
  --shadow-hover: 0 12px 32px rgba(15, 27, 61, 0.12);

  --sidebar-width: 260px;
}

* { box-sizing: border-box; }

body {
  background-color: var(--surface);
  color: var(--text-primary);
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; }

.text-muted-soft { color: var(--text-muted) !important; }
.text-secondary-soft { color: var(--text-secondary) !important; }

/* ------------------------------------------------------------------ *
 * Buttons & badges
 * ------------------------------------------------------------------ */
.btn-brand {
  background: linear-gradient(135deg, var(--blue-500), var(--navy-700));
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: transform .15s ease, box-shadow .15s ease;
}
.btn-brand:hover {
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(47, 91, 224, 0.35);
}
.btn-outline-brand {
  border: 1.5px solid var(--blue-500);
  color: var(--blue-500);
  border-radius: var(--radius-sm);
  font-weight: 600;
  background: transparent;
}
.btn-outline-brand:hover {
  background: var(--blue-500);
  color: #fff;
}

.badge-role-admin { background: #7c3aed; }
.badge-role-instructor { background: var(--blue-500); }
.badge-role-student { background: var(--accent-green); }
.badge-soft {
  color: #fff;
  font-weight: 600;
  font-size: .7rem;
  padding: .3rem .65rem;
  border-radius: 999px;
  letter-spacing: .02em;
}

.badge-difficulty-BEGINNER { background: rgba(34,197,94,.12); color: #16a34a; }
.badge-difficulty-INTERMEDIATE { background: rgba(245,158,11,.14); color: #b45309; }
.badge-difficulty-ADVANCED { background: rgba(239,68,68,.12); color: #dc2626; }
.badge-pill-soft {
  font-weight: 600;
  font-size: .72rem;
  padding: .32rem .7rem;
  border-radius: 999px;
}

/* ------------------------------------------------------------------ *
 * Top navigation
 * ------------------------------------------------------------------ */
.navbar-nova {
  background: linear-gradient(90deg, var(--navy-950), var(--navy-800));
  padding-top: .75rem;
  padding-bottom: .75rem;
  box-shadow: 0 2px 16px rgba(0,0,0,.15);
}
.navbar-nova .navbar-brand {
  color: #fff;
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}
.navbar-nova .navbar-brand span { color: var(--accent-cyan); }
.navbar-nova .nav-link {
  color: rgba(255,255,255,.82);
  font-weight: 500;
  padding: .5rem 1rem !important;
  border-radius: var(--radius-sm);
}
.navbar-nova .nav-link:hover,
.navbar-nova .nav-link.active {
  color: #fff;
  background: rgba(255,255,255,.08);
}
.navbar-nova .btn-outline-light { border-radius: var(--radius-sm); font-weight: 600; }

.avatar-circle {
  width: 38px; height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue-400), var(--accent-cyan));
  color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: .85rem;
  flex-shrink: 0;
}
.avatar-circle-lg { width: 96px; height: 96px; font-size: 1.8rem; }

/* ------------------------------------------------------------------ *
 * Hero / landing page
 * ------------------------------------------------------------------ */
.hero-nova {
  background: radial-gradient(circle at 20% 20%, var(--navy-700), var(--navy-950) 70%);
  color: #fff;
  border-radius: 0 0 2.5rem 2.5rem;
  padding: 5rem 0 6rem;
  position: relative;
  overflow: hidden;
}
.hero-nova::after {
  content: "";
  position: absolute; inset: 0;
  background-image: radial-gradient(circle, rgba(34,211,238,.15) 1px, transparent 1px);
  background-size: 22px 22px;
  opacity: .5;
}
.hero-nova .hero-content { position: relative; z-index: 1; }
.hero-nova h1 { font-weight: 800; letter-spacing: -0.03em; }
.hero-stat {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  backdrop-filter: blur(6px);
}

/* ------------------------------------------------------------------ *
 * Cards
 * ------------------------------------------------------------------ */
.card-nova {
  background: var(--surface-card);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  transition: transform .18s ease, box-shadow .18s ease;
}
.card-nova:hover { box-shadow: var(--shadow-hover); }
.card-nova.hoverable:hover { transform: translateY(-4px); }

.course-card .thumb-wrap {
  aspect-ratio: 16/9;
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  overflow: hidden;
  background: linear-gradient(135deg, var(--navy-700), var(--blue-500));
  display: flex; align-items: center; justify-content: center;
}
.course-card .thumb-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-card .thumb-wrap .placeholder-icon {
  color: rgba(255, 255, 255, 0.55);
  font-size: 2.5rem;
}

.course-card .card-body {
  padding: 1.15rem 1.25rem 1.35rem;
}

.course-card .course-title {
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--text-primary);

  display: -webkit-box;
  -webkit-box-orient: vertical;

  /* Standard property (for future compatibility) */
  line-clamp: 2;

  /* Current browser support */
  -webkit-line-clamp: 2;

  overflow: hidden;
  text-overflow: ellipsis;
}

.stat-card {
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  color: #fff;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-soft);
}
.stat-card .stat-icon {
  width: 46px; height: 46px; border-radius: var(--radius-sm);
  background: rgba(255,255,255,.18);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem;
}
.stat-card h3 { font-weight: 800; letter-spacing: -0.02em; margin-bottom: 0; }
.stat-card-navy { background: linear-gradient(135deg, var(--navy-800), var(--navy-950)); }
.stat-card-blue { background: linear-gradient(135deg, var(--blue-500), var(--navy-700)); }
.stat-card-cyan { background: linear-gradient(135deg, #0891b2, var(--navy-800)); }
.stat-card-amber { background: linear-gradient(135deg, #d97706, var(--navy-900)); }
.stat-card-green { background: linear-gradient(135deg, #16a34a, var(--navy-900)); }

/* ------------------------------------------------------------------ *
 * App shell (sidebar + content) for dashboard & learning screens
 * ------------------------------------------------------------------ */
.app-shell { display: flex; min-height: calc(100vh - 68px); }

.sidebar-nova {
  width: var(--sidebar-width);
  background: var(--navy-950);
  color: #fff;
  flex-shrink: 0;
  padding: 1.5rem 1rem;
  min-height: calc(100vh - 68px);
}
.sidebar-nova .sidebar-heading {
  text-transform: uppercase;
  font-size: .7rem;
  letter-spacing: .08em;
  color: rgba(255,255,255,.4);
  padding: 0 .75rem;
  margin: 1.25rem 0 .5rem;
}
.sidebar-nova .nav-link {
  color: rgba(255,255,255,.78);
  padding: .65rem .9rem;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: .92rem;
  margin-bottom: .15rem;
  display: flex; align-items: center; gap: .65rem;
}
.sidebar-nova .nav-link i { font-size: 1.05rem; width: 20px; text-align: center; }
.sidebar-nova .nav-link:hover { background: rgba(255,255,255,.06); color: #fff; }
.sidebar-nova .nav-link.active {
  background: linear-gradient(90deg, var(--blue-500), var(--navy-700));
  color: #fff;
  box-shadow: 0 4px 14px rgba(47,91,224,.35);
}

.content-nova { flex-grow: 1; padding: 2rem 2.25rem; max-width: 100%; }

@media (max-width: 991.98px) {
  .app-shell { flex-direction: column; }
  .sidebar-nova { width: 100%; min-height: auto; display: flex; overflow-x: auto; gap: .25rem; }
  .sidebar-nova .sidebar-heading { display: none; }
  .sidebar-nova .nav-link { white-space: nowrap; }
  .content-nova { padding: 1.5rem 1rem; }
}

/* ------------------------------------------------------------------ *
 * Progress bars
 * ------------------------------------------------------------------ */
.progress-nova {
  height: 8px;
  border-radius: 999px;
  background: var(--surface-muted);
  overflow: hidden;
}
.progress-nova .progress-bar {
  background: linear-gradient(90deg, var(--blue-400), var(--accent-cyan));
  border-radius: 999px;
}
.progress-nova.lg { height: 12px; }

/* ------------------------------------------------------------------ *
 * Tables
 * ------------------------------------------------------------------ */
.table-nova thead th {
  border-bottom: 2px solid var(--border-soft);
  color: var(--text-secondary);
  font-size: .75rem;
  text-transform: uppercase;
  letter-spacing: .04em;
  font-weight: 700;
}
.table-nova td, .table-nova th { vertical-align: middle; padding: .9rem .75rem; }
.table-nova tbody tr { border-bottom: 1px solid var(--border-soft); }
.table-nova tbody tr:hover { background: var(--surface-muted); }

/* ------------------------------------------------------------------ *
 * Auth pages
 * ------------------------------------------------------------------ */
.auth-shell {
  min-height: calc(100vh - 68px);
  display: flex; align-items: center; justify-content: center;
  background: var(--surface);
  padding: 2.5rem 1rem;
}
.auth-card {
  max-width: 460px; width: 100%;
  background: var(--surface-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-hover);
  padding: 2.5rem;
}
.auth-side-panel {
  background: radial-gradient(circle at 30% 20%, var(--navy-700), var(--navy-950) 75%);
  border-radius: var(--radius-lg);
  color: #fff;
  padding: 2.5rem;
}

/* ------------------------------------------------------------------ *
 * Lesson player
 * ------------------------------------------------------------------ */
.lesson-video-wrap {
  aspect-ratio: 16/9;
  background: #000;
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.lesson-video-wrap iframe { width: 100%; height: 100%; border: 0; }
@media (max-width: 991.98px) {
  .lesson-video-wrap.compact,
  .lesson-video-wrap.compact + .card-nova.compact-align {
    max-width: 100%;
    margin-left: 0;
  }
}
.lesson-list-item {
  border-radius: var(--radius-sm);
  padding: .7rem .85rem;
  display: flex; align-items: center; gap: .7rem;
  color: var(--text-primary);
  font-size: .88rem;
  font-weight: 500;
}
.lesson-list-item:hover { background: var(--surface-muted); }
.lesson-list-item.active { background: rgba(47,91,224,.1); color: var(--blue-500); font-weight: 700; }
.lesson-check {
  width: 22px; height: 22px; border-radius: 50%;
  border: 2px solid var(--border-soft);
  display: flex; align-items: center; justify-content: center;
  font-size: .65rem; flex-shrink: 0; color: transparent;
}
.lesson-check.done { background: var(--accent-green); border-color: var(--accent-green); color: #fff; }

/* ------------------------------------------------------------------ *
 * Misc utilities
 * ------------------------------------------------------------------ */
.rounded-nova { border-radius: var(--radius-lg) !important; }
.section-heading {
  font-weight: 800;
  letter-spacing: -0.02em;
}
.empty-state {
  text-align: center;
  padding: 3.5rem 1.5rem;
  color: var(--text-muted);
}
.empty-state i { font-size: 2.75rem; color: var(--border-soft); }
.footer-nova {
  background: var(--navy-950);
  color: rgba(255,255,255,.6);
  padding: 2rem 0;
  font-size: .88rem;
}