:root {
  --brand-yellow: #f5c518;
  --brand-orange: #f5a623;
  --brand-dark: #1c1c28;
  --brand-dark-2: #24243a;
  --ink: #1b1d28;
  --ink-soft: #6b7080;
  --surface: #ffffff;
  --surface-muted: #f6f7fb;
  --border-soft: #ecedf3;
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 3px rgba(20, 20, 40, .06), 0 1px 2px rgba(20,20,40,.04);
  --shadow-md: 0 8px 24px rgba(20, 20, 40, .09);
  --shadow-lg: 0 20px 50px rgba(20, 20, 40, .16);
  --grad-brand: linear-gradient(135deg, var(--brand-yellow) 0%, var(--brand-orange) 100%);
}

* { scrollbar-width: thin; }

body {
  font-family: 'Inter', 'Noto Sans Thai', 'Segoe UI', sans-serif;
  background: var(--surface-muted);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 { letter-spacing: -0.01em; }

a { transition: color .15s ease; }

/* ---------- Buttons: soften the stock Bootstrap look without renaming classes ---------- */
.btn { border-radius: var(--radius-sm); font-weight: 600; letter-spacing: .01em; transition: transform .12s ease, box-shadow .12s ease, filter .12s ease; }
.btn:active { transform: translateY(1px); }
.btn-warning { background: var(--grad-brand); border: none; color: #221a00; box-shadow: 0 6px 16px rgba(245, 166, 35, .32); }
.btn-warning:hover, .btn-warning:focus { filter: brightness(1.04); color: #221a00; box-shadow: 0 8px 20px rgba(245, 166, 35, .4); }
.btn-lg { border-radius: var(--radius-md); }
.btn-danger { box-shadow: 0 6px 16px rgba(220, 53, 69, .25); }
.btn-outline-primary { border-radius: var(--radius-sm); }
.form-control, .form-select { border-radius: var(--radius-sm); border-color: var(--border-soft); padding: 10px 14px; }
.form-control:focus, .form-select:focus { border-color: var(--brand-orange); box-shadow: 0 0 0 .2rem rgba(245, 166, 35, .15); }
.form-control-lg, .form-select-lg { border-radius: 12px; }
.alert { border-radius: var(--radius-sm); border: none; }
.alert-success { background: #eafaf0; color: #1e7a44; }
.alert-danger { background: #fdeeee; color: #b3261e; }
.alert-warning { background: #fff6e0; color: #8a5c00; }
.alert-info { background: #eef4ff; color: #2a5db0; }
.badge { font-weight: 600; letter-spacing: .01em; }

/* ---------- Auth pages ---------- */
.auth-bg {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(circle at 15% 15%, #fff6e0 0%, transparent 45%),
              radial-gradient(circle at 85% 85%, #ffe4b8 0%, transparent 45%),
              linear-gradient(135deg, #fffaf0 0%, #ffedd0 100%);
  padding: 24px;
  position: relative;
}
.auth-lang-switch {
  position: absolute;
  top: 18px;
  right: 22px;
  font-size: 0.8rem;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.auth-lang-switch a { color: #8a6d3b; text-decoration: none; font-weight: 700; }
.auth-lang-switch a.active, .auth-lang-switch a:hover { color: #1c1c28; }
.auth-lang-switch .lang-switch-sep { color: #c9b280; }
.auth-wrap { width: 100%; max-width: 420px; }
.auth-wrap-lg { max-width: 640px; }
.auth-card { background: var(--surface); border-radius: var(--radius-lg); padding: 40px; box-shadow: var(--shadow-lg); border: 1px solid rgba(255,255,255,.6); }
.auth-logo { font-size: 3rem; color: var(--brand-orange); filter: drop-shadow(0 6px 14px rgba(245,166,35,.35)); }
.admin-login-bg { background: radial-gradient(circle at 15% 15%, #eef0fb 0%, transparent 45%), radial-gradient(circle at 85% 85%, #d7dcf6 0%, transparent 45%), linear-gradient(135deg, #e7e9f5 0%, #cfd3ec 100%); }

/* ---------- Navbar ---------- */
.app-navbar { background: linear-gradient(120deg, var(--brand-dark) 0%, var(--brand-dark-2) 100%) !important; box-shadow: 0 2px 16px rgba(0,0,0,.18); }
.notif-badge { font-size: 0.6rem; position: absolute; top: 2px; right: -2px; }
.notif-dropdown { width: 320px; max-height: 400px; overflow-y: auto; border-radius: var(--radius-md); border: none; box-shadow: var(--shadow-lg); }
.notif-item { padding: 10px 12px; border-radius: var(--radius-sm); cursor: pointer; transition: background .12s ease; }
.notif-item:hover { background: var(--surface-muted); }
.notif-item.unread { background: #fff6e0; }
.notif-msg { font-size: 0.85rem; }
.notif-time { font-size: 0.72rem; color: #888; }
.notif-link { font-size: 0.75rem; }
.lang-switch { display: inline-flex; align-items: center; gap: 6px; font-size: 0.8rem; padding: 6px 10px; }
.lang-switch a { color: rgba(255,255,255,.55); text-decoration: none; font-weight: 600; letter-spacing: .03em; }
.lang-switch a.active, .lang-switch a:hover { color: #fff; }
.lang-switch-sep { color: rgba(255,255,255,.3); }
.lang-switch-admin { padding: 10px 16px; }
.lang-switch-admin a { color: rgba(255,255,255,.55); }
.lang-switch-admin a.active, .lang-switch-admin a:hover { color: #fff; }

/* ---------- Course cards ---------- */
.course-card { border-radius: var(--radius-lg); overflow: hidden; background: var(--surface); box-shadow: var(--shadow-sm); transition: transform .18s ease, box-shadow .18s ease; border: 1px solid var(--border-soft); }
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.course-card-header { background: var(--course-color, var(--brand-orange)); background-image: linear-gradient(135deg, rgba(255,255,255,.18), rgba(0,0,0,.08)), linear-gradient(135deg, var(--course-color, var(--brand-orange)), var(--course-color, var(--brand-orange))); padding: 24px 20px; height: 90px; display: flex; align-items: flex-start; }
.course-card-header.has-cover-image {
  background-image: linear-gradient(to bottom, rgba(0,0,0,.15), rgba(0,0,0,.45)), var(--course-cover-image);
  background-size: cover;
  background-position: center;
}
.course-code { color: #fff; font-weight: 700; font-size: 1.1rem; text-shadow: 0 1px 3px rgba(0,0,0,.3); }
.course-card-body { padding: 16px 20px; color: #222; }
.btn-join-class { width: 100%; margin-top: 14px; }

/* ---------- Week list (classroom.php) ---------- */
.badge.fs-6 { border-radius: 999px; padding: 8px 16px; box-shadow: var(--shadow-sm); }

.week-card {
  position: relative;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-soft);
  overflow: hidden;
  transition: box-shadow .2s ease, transform .2s ease, border-color .2s ease;
}
.week-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; bottom: 0;
  width: 6px;
  background: var(--grad-brand);
  opacity: .5;
  transition: opacity .2s ease, width .2s ease;
}
.week-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }
.week-card:hover::before { opacity: 1; width: 8px; }

.week-current { border-color: var(--brand-orange); box-shadow: 0 0 0 3px rgba(245,166,35,.14); }
.week-current::before { opacity: 1; width: 8px; }

.week-card .card-body { padding: 18px 22px 18px 28px; }
.week-card h6 { font-size: 1.03rem; letter-spacing: -0.01em; color: var(--ink); margin-bottom: 4px; }
.week-card small.text-muted { display: inline-flex; align-items: center; gap: 6px; font-size: .8rem; }
.week-card small.text-muted::before { content: '📅'; font-size: .82rem; }

.week-card .badge.bg-success {
  background: linear-gradient(135deg, #34d399, #10b981) !important;
  border-radius: 999px;
  padding: 5px 12px;
  font-weight: 700;
  letter-spacing: .02em;
  box-shadow: 0 0 0 0 rgba(16,185,129,.5);
  animation: week-pulse 2s infinite;
}
@keyframes week-pulse {
  0%   { box-shadow: 0 0 0 0 rgba(16,185,129,.45); }
  70%  { box-shadow: 0 0 0 8px rgba(16,185,129,0); }
  100% { box-shadow: 0 0 0 0 rgba(16,185,129,0); }
}

.week-card .bi-chevron-right { color: var(--ink-soft); transition: transform .2s ease, color .2s ease; }
.week-card:hover .bi-chevron-right { transform: translateX(4px); color: var(--brand-orange); }

#weekAccordion > .alert-info {
  border-radius: var(--radius-md);
  text-align: center;
  padding: 36px 20px;
  background: var(--surface);
  border: 1px dashed var(--border-soft);
  color: var(--ink-soft);
  box-shadow: none;
}

/* ---------- Week detail / module sidebar ---------- */
.week-sidebar { background: var(--surface); border-radius: var(--radius-lg); padding: 16px; box-shadow: var(--shadow-sm); }
.section-block { margin-bottom: 18px; }
.section-label { font-size: 0.75rem; text-transform: uppercase; color: #999; font-weight: 700; margin-bottom: 6px; letter-spacing: .06em; }
.module-link { display: flex; align-items: center; gap: 8px; padding: 10px 12px; border-radius: var(--radius-sm); color: #333; text-decoration: none; font-size: 0.9rem; transition: background .12s ease; }
.module-link:hover { background: var(--surface-muted); }
.module-link.active { background: var(--grad-brand); color: #221a00; font-weight: 600; box-shadow: 0 4px 12px rgba(245,166,35,.28); }
.module-panel { background: var(--surface); border-radius: var(--radius-lg); padding: 28px; min-height: 400px; box-shadow: var(--shadow-sm); position: relative; }

/* ---------- Week detail page (week.php) — extra polish ---------- */
.week-sidebar { position: relative; overflow: hidden; }
.week-sidebar::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 5px;
  background: var(--grad-brand);
}
.week-sidebar h6 { display: flex; align-items: center; gap: 8px; font-size: 1.05rem; letter-spacing: -0.01em; margin-top: 4px; }
.week-sidebar h6::before { content: '🗓️'; font-size: 1rem; }
.week-sidebar > small.text-muted {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--surface-muted); padding: 6px 12px; border-radius: 999px; font-size: .76rem;
}

.section-label { display: inline-flex; align-items: center; gap: 6px; padding: 4px 10px; border-radius: 999px; background: var(--surface-muted); }
.section-block:nth-of-type(1) .section-label { color: #6d4fc7; background: #f1ecfb; }
.section-block:nth-of-type(2) .section-label { color: #b5620b; background: #fff2df; }
.section-block:nth-of-type(3) .section-label { color: #1e8a5f; background: #e6f8f0; }

.module-link { border: 1px solid transparent; }
.module-link:hover { border-color: var(--border-soft); transform: translateX(2px); }
.module-link.active { box-shadow: 0 4px 12px rgba(245,166,35,.28); }
.module-link i { width: 20px; text-align: center; }

.module-panel > .alert-info {
  border-radius: var(--radius-md);
  text-align: center;
  padding: 48px 20px;
  background: var(--surface-muted);
  border: 1px dashed var(--border-soft);
  color: var(--ink-soft);
  font-size: .95rem;
  box-shadow: none;
}
.module-panel > .alert-info::before { content: '📭'; display: block; font-size: 2rem; margin-bottom: 10px; }

.d-flex.align-items-center.gap-2.mb-2.flex-wrap a.small {
  display: inline-flex; align-items: center; gap: 6px;
  font-weight: 600; color: var(--ink-soft); text-decoration: none;
  transition: color .15s ease, transform .15s ease;
}
.d-flex.align-items-center.gap-2.mb-2.flex-wrap a.small:hover { color: var(--brand-orange); transform: translateX(-2px); }

.choice-option { border: 1px solid var(--border-soft); border-radius: var(--radius-sm); padding: 10px 14px; transition: border-color .12s ease, background .12s ease; }
.choice-option:hover { border-color: var(--brand-orange); background: #fffaf0; }

/* ---------- Meeting lock overlay ---------- */
.meeting-lock-overlay {
  position: fixed; inset: 0; background: rgba(10,10,20,.78); backdrop-filter: blur(3px); z-index: 2000;
  display: flex; align-items: center; justify-content: center; flex-direction: column; gap: 16px; padding: 20px;
}
.meeting-lock-card {
  background: var(--surface); border-radius: var(--radius-lg); padding: 40px; text-align: center; max-width: 480px;
  box-shadow: var(--shadow-lg); animation: pulse 1.5s infinite;
}
.meeting-lock-card i { font-size: 3rem; color: #dc3545; }
@keyframes pulse { 0%,100% { transform: scale(1); } 50% { transform: scale(1.02); } }

/* ---------- Meeting room ---------- */
.meeting-body { background: #101018; margin: 0; height: 100vh; overflow: hidden; }
.meeting-shell { display: flex; flex-direction: column; height: 100vh; }
.meeting-topbar { display: flex; justify-content: space-between; align-items: center; padding: 12px 20px; color: #fff; background: linear-gradient(120deg, var(--brand-dark), var(--brand-dark-2)); box-shadow: 0 2px 12px rgba(0,0,0,.25); }
.meeting-main { flex: 1; display: flex; overflow: hidden; }
.video-grid { flex: 1; display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 10px; padding: 16px; overflow-y: auto; align-content: start; }
.contents-grid { display: contents; }
.video-tile { position: relative; background: #000; border-radius: var(--radius-md); overflow: hidden; aspect-ratio: 16/9; box-shadow: 0 4px 18px rgba(0,0,0,.35); }
.video-tile video { width: 100%; height: 100%; object-fit: cover; }
.video-label { position: absolute; bottom: 8px; left: 8px; background: rgba(0,0,0,.55); backdrop-filter: blur(2px); color: #fff; font-size: 0.75rem; padding: 3px 10px; border-radius: 999px; }
.chat-panel { width: 280px; background: linear-gradient(180deg, var(--brand-dark), var(--brand-dark-2)); color: #fff; display: flex; flex-direction: column; border-left: 1px solid rgba(255,255,255,.08); }
.chat-header { padding: 12px; font-weight: 600; border-bottom: 1px solid rgba(255,255,255,.08); }
.chat-log { flex: 1; overflow-y: auto; padding: 10px; font-size: 0.85rem; }
.chat-msg { margin-bottom: 8px; }
.chat-msg.me { text-align: right; color: var(--brand-yellow); }
.chat-input-row { display: flex; gap: 6px; padding: 10px; }
.chat-input-row .form-control { background: rgba(255,255,255,.06); border-color: rgba(255,255,255,.12); color: #fff; }
.chat-input-row .form-control::placeholder { color: rgba(255,255,255,.4); }
.chat-close-btn { display: none; background: none; border: none; color: #fff; font-size: 1.2rem; }
.meeting-controls { display: flex; justify-content: center; align-items: center; gap: 16px; padding: 16px; background: linear-gradient(0deg, var(--brand-dark), var(--brand-dark-2)); flex-wrap: wrap; position: relative; }
.control-btn { width: 52px; height: 52px; font-size: 1.2rem; display: flex; align-items: center; justify-content: center; position: relative; flex-shrink: 0; box-shadow: 0 4px 14px rgba(0,0,0,.3); transition: transform .12s ease; }
.control-btn:hover { transform: translateY(-2px); }
.control-btn .unread-dot { position: absolute; top: 4px; right: 4px; width: 10px; height: 10px; border-radius: 50%; background: #dc3545; border: 2px solid #1c1c28; display: none; }
.control-btn.has-unread .unread-dot { display: block; }

/* ---------- Screen share: enlarge the shared tile immediately ---------- */
.video-tile.tile-featured {
  grid-column: 1 / -1;
  order: -1;
  aspect-ratio: 16 / 9;
  max-height: 70vh;
}

/* ---------- Mobile responsive meeting room ---------- */
@media (max-width: 860px) {
  .meeting-main { position: relative; overflow: hidden; }
  .video-grid { width: 100%; }
  .chat-panel {
    position: fixed;
    top: 0; right: 0; bottom: 0;
    width: 88vw;
    max-width: 340px;
    transform: translateX(100%);
    transition: transform .25s ease;
    z-index: 1050;
    box-shadow: -6px 0 24px rgba(0,0,0,.5);
  }
  .chat-panel.chat-open { transform: translateX(0); }
  .chat-close-btn { display: inline-flex; align-items: center; justify-content: center; }
  .meeting-controls { gap: 10px; padding: 12px 8px; }
  .control-btn { width: 46px; height: 46px; font-size: 1.05rem; }
  .meeting-topbar { flex-wrap: wrap; gap: 4px; padding: 8px 12px; }
}

.embed-code-wrap iframe, .embed-code-wrap video, .embed-code-wrap embed, .embed-code-wrap object {
  border-radius: var(--radius-md);
}

/* ---------- Media embed fallback (broken/missing video, image, audio file) ---------- */
.media-embed { position: relative; margin-bottom: 1rem; }
.media-fallback { display: none; }
.media-embed.media-error video,
.media-embed.media-error img,
.media-embed.media-error audio { display: none; }
.media-embed.media-error .media-fallback { display: flex; }
.media-fallback {
  flex-direction: column; align-items: center; justify-content: center; gap: 10px;
  background: var(--surface-muted); border: 1px dashed var(--border-soft); border-radius: var(--radius-md);
  padding: 40px 20px; color: var(--ink-soft); text-align: center;
}
.media-fallback i { font-size: 2rem; color: #dc9b1a; }
.media-fallback p { max-width: 380px; margin: 0; font-size: .88rem; }

/* ---------- Exam ---------- */
.exam-question-image { display: block; max-height: 360px; border-radius: var(--radius-sm); border: 1px solid var(--border-soft); box-shadow: var(--shadow-sm); }
.exam-timer { font-size: 1.4rem; font-weight: 700; color: #dc3545; background: #fff0f0; padding: 4px 16px; border-radius: var(--radius-sm); box-shadow: inset 0 0 0 1px rgba(220,53,69,.15); }