:root {
  --bg: #07111d;
  --panel: rgba(17, 24, 39, 0.92);
  --panel-2: rgba(12, 18, 30, 0.92);
  --border: rgba(255,255,255,0.08);
  --text: #eef4ff;
  --muted: #9fb0cf;
  --accent: #4da3ff;
  --success: #3fb950;
  --danger: #ef4444;
  --shadow: 0 18px 48px rgba(0,0,0,0.35);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background:
    radial-gradient(circle at top right, rgba(77,163,255,0.16), transparent 26%),
    linear-gradient(180deg, #050b14 0%, #091221 100%);
  color: var(--text);
}
a { color: inherit; text-decoration: none; }

.academy-shell {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.academy-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(7,17,29,0.88);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(10px);
}
.academy-header .academy-shell {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 16px 0;
}
.academy-brand {
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}
.academy-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.academy-nav a {
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid transparent;
  color: var(--muted);
}
.academy-nav a:hover {
  color: var(--text);
  border-color: var(--border);
  background: rgba(255,255,255,0.04);
}

.academy-main {
  padding: 34px 0 70px;
}

.hero,
.card {
  background: linear-gradient(180deg, var(--panel), var(--panel-2));
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: var(--shadow);
}
.hero {
  padding: 28px;
  margin-bottom: 20px;
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: center;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.78rem;
  font-weight: 800;
}
.muted {
  color: var(--muted);
  line-height: 1.7;
}

.stats-grid,
.lesson-grid {
  display: grid;
  gap: 18px;
}
.stats-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-bottom: 18px;
}
.lesson-grid {
  grid-template-columns: 1.1fr 0.9fr;
}
.card {
  padding: 24px;
}
.toolbar {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  margin-bottom: 18px;
}
.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.filter-btn,
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  font-weight: 800;
}
.filter-btn {
  background: rgba(255,255,255,0.04);
  color: var(--text);
  border-color: var(--border);
}
.filter-btn.active {
  background: linear-gradient(135deg, var(--accent), #3ec7ff);
  color: #06101b;
}
.btn.primary {
  background: linear-gradient(135deg, var(--accent), #3ec7ff);
  color: #06101b;
}
.btn.secondary,
.btn.ghost {
  background: rgba(255,255,255,0.04);
  color: var(--text);
  border-color: var(--border);
}

.academy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}
.lesson-tile {
  padding: 18px;
  border-radius: 18px;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.03);
}
.lesson-tile h3 {
  margin: 8px 0 10px;
}
.lesson-tile p {
  color: var(--muted);
  line-height: 1.6;
}
.lesson-tile-top {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
}
.path-pill {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(77,163,255,0.12);
  border: 1px solid rgba(77,163,255,0.3);
  color: #dcecff;
  font-size: 0.82rem;
}
.done-pill {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(63,185,80,0.12);
  border: 1px solid rgba(63,185,80,0.3);
  color: #d8ffe1;
  font-size: 0.82rem;
}

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 16px;
}
.meta-chip {
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.04);
  color: var(--muted);
  font-size: 0.9rem;
}
.lesson-body p,
.lesson-body li {
  color: var(--muted);
  line-height: 1.8;
}
.lesson-body ul {
  padding-left: 20px;
}
.video-wrap {
  margin-top: 22px;
}
.video-slot {
  border-radius: 18px;
  border: 1px dashed rgba(77,163,255,0.35);
  background: rgba(255,255,255,0.03);
  padding: 20px;
}
.video-slot iframe {
  width: 100%;
  aspect-ratio: 16 / 9;
  border: 0;
  border-radius: 12px;
}
.video-placeholder {
  color: var(--muted);
}

.quiz-form {
  display: grid;
  gap: 16px;
}
.quiz-item label {
  display: block;
  margin-bottom: 8px;
  font-weight: 700;
}
.quiz-item select {
  width: 100%;
  padding: 12px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--text);
}
.divider {
  margin: 24px 0;
  border: none;
  border-top: 1px solid var(--border);
}
.unlock-box {
  margin-top: 24px;
  padding: 18px;
  border-radius: 18px;
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.03);
}

@media (max-width: 980px) {
  .stats-grid,
  .lesson-grid {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 780px) {
  .academy-header .academy-shell,
  .hero,
  .toolbar {
    flex-direction: column;
    align-items: flex-start;
  }
}