/* ── Upload tab panels ───────────────────────────────────────────────────── */
.upload-tab-panel { display: none; }
.upload-tab-panel.active { display: block; }

/* ── Reset & Base ─────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --cf-orange: #f6821f;
  --cf-orange-dark: #d46b10;
  --bg: #0f0f0f;
  --bg-card: #1a1a1a;
  --bg-card2: #242424;
  --border: #2e2e2e;
  --text: #e8e8e8;
  --text-muted: #888;
  --text-dim: #555;
  --danger: #e53e3e;
  --success: #38a169;
  --radius: 8px;
  --transition: 150ms ease;
}

html { font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

a { color: var(--cf-orange); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── Layout ───────────────────────────────────────────────────────────────── */
.app-shell { display: flex; flex-direction: column; min-height: 100vh; }

nav.topnav {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 24px;
  height: 56px;
  background: #111;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.topnav .logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--cf-orange);
  letter-spacing: -0.5px;
  flex-shrink: 0;
}
.topnav .search-box {
  flex: 1;
  max-width: 480px;
  position: relative;
}
.topnav .search-box input {
  width: 100%;
  padding: 7px 12px 7px 36px;
  background: var(--bg-card2);
  border: 1px solid var(--border);
  border-radius: 20px;
  color: var(--text);
  font-size: 0.875rem;
  outline: none;
  transition: border-color var(--transition);
}
.topnav .search-box input:focus { border-color: var(--cf-orange); }
.topnav .search-box .icon {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 0.875rem;
}
.topnav .nav-links { display: flex; gap: 4px; margin-left: auto; align-items: center; }
.topnav .nav-links a, .topnav .nav-links button {
  padding: 6px 12px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  color: var(--text-muted);
  background: none;
  border: none;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.topnav .nav-links a:hover, .topnav .nav-links button:hover {
  background: var(--bg-card2);
  color: var(--text);
  text-decoration: none;
}
.topnav .avatar {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--cf-orange);
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 0.8rem; color: #fff;
  cursor: pointer;
}

.page-content { flex: 1; padding: 32px 24px; max-width: 1200px; margin: 0 auto; width: 100%; }
.page-content.wide { max-width: 100%; padding: 0; }

/* ── Cards ────────────────────────────────────────────────────────────────── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.card + .card { margin-top: 16px; }

/* ── Buttons ──────────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 9px 18px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: opacity var(--transition), background var(--transition);
}
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary { background: var(--cf-orange); color: #fff; }
.btn-primary:hover { background: var(--cf-orange-dark); }
.btn-secondary { background: var(--bg-card2); color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover { background: var(--border); }
.btn-danger { background: var(--danger); color: #fff; }
.btn-sm { padding: 5px 12px; font-size: 0.8rem; }
.btn-icon { padding: 7px; border-radius: 6px; background: var(--bg-card2); border: 1px solid var(--border); color: var(--text-muted); cursor: pointer; transition: background var(--transition); }
.btn-icon:hover { background: var(--border); color: var(--text); }

/* ── Forms ────────────────────────────────────────────────────────────────── */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 0.875rem; color: var(--text-muted); margin-bottom: 6px; }
.form-control {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-card2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.9rem;
  outline: none;
  transition: border-color var(--transition);
}
.form-control:focus { border-color: var(--cf-orange); }
textarea.form-control { resize: vertical; min-height: 80px; }
select.form-control { cursor: pointer; }

/* ── Grid ─────────────────────────────────────────────────────────────────── */
.grid-2 { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 16px; }

/* ── Folder / Video Cards ─────────────────────────────────────────────────── */
.folder-card, .video-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  cursor: pointer;
  transition: border-color var(--transition), transform var(--transition);
  text-decoration: none;
  color: var(--text);
  display: block;
}
.folder-card:hover, .video-card:hover {
  border-color: var(--cf-orange);
  transform: translateY(-2px);
  text-decoration: none;
}
.folder-card .folder-icon { font-size: 2rem; margin-bottom: 12px; }
.folder-card h3, .video-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: 4px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.folder-card p, .video-card p { font-size: 0.8rem; color: var(--text-muted); }

.video-thumb {
  width: 100%;
  aspect-ratio: 16/9;
  background: var(--bg-card2);
  border-radius: 6px;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  color: var(--text-dim);
  overflow: hidden;
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; }

.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 20px;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.badge-processing { background: #2d3748; color: #a0aec0; }
.badge-ready { background: #1a4731; color: #68d391; }
.badge-error { background: #3d1515; color: #fc8181; }
.badge-live { background: #3d1515; color: #fc8181; animation: pulse 1.5s infinite; }
@keyframes pulse { 0%,100% { opacity:1; } 50% { opacity:0.6; } }

/* ── Player Layout ────────────────────────────────────────────────────────── */
.player-layout {
  display: grid;
  grid-template-columns: 1fr 360px;
  grid-template-rows: auto 1fr;
  height: calc(100vh - 56px);
  overflow: hidden;
}
.player-main { grid-column: 1; grid-row: 1/3; display: flex; flex-direction: column; overflow: hidden; }
.player-sidebar { grid-column: 2; grid-row: 1/3; border-left: 1px solid var(--border); display: flex; flex-direction: column; overflow: hidden; }

.video-wrapper {
  position: relative;
  background: #000;
  width: 100%;
}
.video-wrapper iframe {
  width: 100%;
  aspect-ratio: 16/9;
  display: block;
  border: none;
}

/* Heatmap overlay canvas — absolutely positioned over the iframe */
.heatmap-canvas {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 4px;
  pointer-events: none;
}

/* Chapter bar */
.chapter-bar {
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 10px 16px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  overflow-y: auto;
  max-height: 80px;
}
.chapter-chip {
  padding: 4px 10px;
  background: var(--bg-card2);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.75rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--transition);
}
.chapter-chip:hover { background: var(--border); }
.chapter-chip .time { color: var(--cf-orange); margin-right: 4px; }

/* Sidebar tabs */
.sidebar-tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.sidebar-tab {
  flex: 1;
  padding: 12px 8px;
  text-align: center;
  font-size: 0.8rem;
  cursor: pointer;
  color: var(--text-muted);
  border-bottom: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition);
  background: none;
  border-top: none;
  border-left: none;
  border-right: none;
}
.sidebar-tab.active { color: var(--cf-orange); border-bottom-color: var(--cf-orange); }
.sidebar-panel { flex: 1; overflow-y: auto; padding: 16px; display: none; }
.sidebar-panel.active { display: block; }

/* Notes */
.note-item {
  padding: 10px;
  background: var(--bg-card2);
  border-radius: 6px;
  margin-bottom: 8px;
  font-size: 0.85rem;
}
.note-item .note-time { color: var(--cf-orange); font-size: 0.75rem; font-weight: 600; cursor: pointer; }
.note-item .note-text { margin-top: 4px; color: var(--text); }
.note-item .note-meta { font-size: 0.7rem; color: var(--text-muted); margin-top: 4px; }
.note-form { display: flex; gap: 8px; margin-top: 12px; }
.note-form textarea { flex: 1; height: 60px; font-size: 0.85rem; }

/* Transcript */
.transcript-segment {
  padding: 6px 8px;
  border-radius: 4px;
  font-size: 0.85rem;
  cursor: pointer;
  line-height: 1.5;
  transition: background var(--transition);
}
.transcript-segment:hover { background: var(--bg-card2); }
.transcript-segment.active { background: rgba(246,130,31,0.15); color: var(--cf-orange); }
.transcript-segment .seg-time { font-size: 0.7rem; color: var(--text-muted); display: block; }
mark { background: rgba(246,130,31,0.3); color: var(--text); border-radius: 2px; padding: 0 2px; }

/* Quiz overlay */
.quiz-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  display: none;
}
.quiz-overlay.active { display: flex; }
.quiz-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  max-width: 480px;
  width: 90%;
}
.quiz-box h3 { margin-bottom: 20px; font-size: 1.1rem; }
.quiz-option {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--bg-card2);
  border: 1px solid var(--border);
  border-radius: 6px;
  margin-bottom: 10px;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
  font-size: 0.9rem;
}
.quiz-option:hover { border-color: var(--cf-orange); background: rgba(246,130,31,0.05); }
.quiz-option.correct { border-color: var(--success); background: rgba(56,161,105,0.1); }
.quiz-option.wrong { border-color: var(--danger); background: rgba(229,62,62,0.1); }
.quiz-result { margin-top: 16px; font-size: 0.9rem; font-weight: 600; }
.quiz-result.correct { color: var(--success); }
.quiz-result.wrong { color: var(--danger); }

/* ── Login Page ───────────────────────────────────────────────────────────── */
.login-shell {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
}
.login-box {
  width: 100%;
  max-width: 400px;
  padding: 40px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
}
.login-box .logo { font-size: 1.5rem; font-weight: 700; color: var(--cf-orange); margin-bottom: 8px; }
.login-box .subtitle { color: var(--text-muted); font-size: 0.875rem; margin-bottom: 28px; }
.otp-inputs { display: flex; gap: 8px; justify-content: center; margin: 20px 0; }
.otp-inputs input {
  width: 44px; height: 52px;
  text-align: center;
  font-size: 1.4rem;
  font-weight: 700;
  background: var(--bg-card2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  outline: none;
  transition: border-color var(--transition);
}
.otp-inputs input:focus { border-color: var(--cf-orange); }

/* ── Upload Page ──────────────────────────────────────────────────────────── */
.drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 48px;
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
}
.drop-zone:hover, .drop-zone.drag-over {
  border-color: var(--cf-orange);
  background: rgba(246,130,31,0.04);
}
.drop-zone .drop-icon { font-size: 3rem; margin-bottom: 12px; color: var(--text-dim); }
.drop-zone p { color: var(--text-muted); font-size: 0.9rem; }
.drop-zone strong { color: var(--cf-orange); }

.upload-progress { margin-top: 16px; }
.progress-bar {
  height: 6px;
  background: var(--bg-card2);
  border-radius: 3px;
  overflow: hidden;
  margin-top: 8px;
}
.progress-fill {
  height: 100%;
  background: var(--cf-orange);
  transition: width 0.3s ease;
  width: 0%;
}

/* ── Admin / Tables ───────────────────────────────────────────────────────── */
table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
th { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); color: var(--text-muted); font-weight: 500; }
td { padding: 12px; border-bottom: 1px solid var(--border); }
tr:last-child td { border-bottom: none; }
tr:hover td { background: var(--bg-card2); }

.role-badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 20px;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
}
.role-admin    { background: rgba(246,130,31,0.2); color: var(--cf-orange); }
.role-creator  { background: rgba(99,179,237,0.2); color: #63b3ed; }
.role-ta       { background: rgba(154,230,180,0.2); color: #9ae6b4; }
.role-viewer   { background: rgba(113,128,150,0.2); color: #718096; }

/* ── Analytics Stats ──────────────────────────────────────────────────────── */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 16px; margin-bottom: 24px; }
.stat-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
.stat-card .stat-value { font-size: 2rem; font-weight: 700; color: var(--cf-orange); }
.stat-card .stat-label { font-size: 0.8rem; color: var(--text-muted); margin-top: 4px; }

/* ── Misc ─────────────────────────────────────────────────────────────────── */
.page-header { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
.page-header h1 { font-size: 1.5rem; font-weight: 700; }
.spacer { flex: 1; }
.text-muted { color: var(--text-muted); }
.text-sm { font-size: 0.8rem; }
.mt-4 { margin-top: 16px; }
.mt-8 { margin-top: 32px; }
.mb-4 { margin-bottom: 16px; }
.flex { display: flex; }
.items-center { align-items: center; }
.gap-2 { gap: 8px; }
.gap-4 { gap: 16px; }

.alert {
  padding: 12px 16px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  margin-bottom: 16px;
}
.alert-error { background: rgba(229,62,62,0.1); border: 1px solid rgba(229,62,62,0.3); color: #fc8181; }
.alert-success { background: rgba(56,161,105,0.1); border: 1px solid rgba(56,161,105,0.3); color: #68d391; }

.empty-state {
  text-align: center;
  padding: 64px 24px;
  color: var(--text-muted);
}
.empty-state .empty-icon { font-size: 3rem; margin-bottom: 12px; opacity: 0.5; }

.spinner {
  width: 20px; height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--cf-orange);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  display: inline-block;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Responsive ───────────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .player-layout { grid-template-columns: 1fr; grid-template-rows: auto auto 1fr; height: auto; }
  .player-main { grid-column: 1; grid-row: 1; }
  .player-sidebar { grid-column: 1; grid-row: 2; border-left: none; border-top: 1px solid var(--border); height: 400px; }
  .topnav .search-box { display: none; }
  .page-content { padding: 16px; }
}