/* ============================================================
   IATechLabs LMS — App Styles
============================================================ */

:root {
  --bg:      #020713;
  --bg2:     #0c1528;
  --bg3:     #121f38;
  --text:    #f5f7fb;
  --muted:   #a7b0c0;
  --line:    rgba(255,255,255,.09);
  --line2:   rgba(255,255,255,.16);
  --blue:    #1f7aff;
  --orange:  #ff6b18;
  --violet:  #8b5cf6;
  --green:   #22c55e;
  --red:     #ef4444;
  --radius:  16px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
h1,h2,h3,h4,p { margin-top: 0; }
button { font-family: inherit; cursor: pointer; }

/* ── Scrollbar ─────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg2); }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,.14); border-radius: 3px; }

/* ── Loading overlay ───────────────────────────────────── */
#loading {
  position: fixed; inset: 0;
  background: var(--bg);
  display: flex; align-items: center; justify-content: center;
  z-index: 9999;
  transition: opacity .3s ease;
}
#loading.hidden { opacity: 0; pointer-events: none; }
.spinner {
  width: 40px; height: 40px;
  border: 3px solid var(--line);
  border-top-color: var(--blue);
  border-radius: 50%;
  animation: spin .7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── App shell ─────────────────────────────────────────── */
.app-layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}
.sidebar {
  background: var(--bg2);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  padding: 0;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}
.sidebar-brand {
  padding: 24px 20px 20px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  gap: 10px;
}
.sidebar-brand svg { width: 32px; height: 32px; flex-shrink: 0; }
.sidebar-brand .brand-name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -.04em;
  color: #fff;
}
.sidebar-brand .brand-name span { color: var(--orange); }
.sidebar-brand .brand-sub {
  font-size: 10px;
  color: rgba(255,255,255,.4);
  letter-spacing: .06em;
  text-transform: uppercase;
  display: block;
  margin-top: 2px;
}
.sidebar-nav {
  flex: 1;
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.nav-label {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: rgba(255,255,255,.3);
  padding: 12px 8px 6px;
}
.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 10px;
  font-size: 14px;
  color: rgba(255,255,255,.65);
  transition: background .15s ease, color .15s ease;
  cursor: pointer;
}
.nav-item:hover { background: rgba(255,255,255,.06); color: #fff; }
.nav-item.active { background: rgba(31,122,255,.14); color: var(--blue); font-weight: 600; }
.nav-item svg { width: 18px; height: 18px; flex-shrink: 0; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.sidebar-footer {
  padding: 16px 12px;
  border-top: 1px solid var(--line);
}
.user-chip {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 10px;
  background: rgba(255,255,255,.04);
  border: 1px solid var(--line);
}
.user-avatar {
  width: 34px; height: 34px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue), var(--orange));
  display: grid; place-items: center;
  font-size: 13px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}
.user-info { flex: 1; min-width: 0; }
.user-name { font-size: 13px; font-weight: 600; color: #fff; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.user-role { font-size: 10px; color: var(--muted); letter-spacing: .04em; text-transform: uppercase; }
.btn-logout {
  background: none;
  border: none;
  padding: 4px;
  color: var(--muted);
  border-radius: 6px;
  display: grid; place-items: center;
  transition: color .15s, background .15s;
}
.btn-logout:hover { color: var(--red); background: rgba(239,68,68,.08); }
.btn-logout svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* ── Main content ──────────────────────────────────────── */
.main {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.topbar {
  padding: 20px 32px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: rgba(2,7,19,.8);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.topbar-title { font-size: 18px; font-weight: 700; letter-spacing: -.03em; }
.topbar-sub { font-size: 13px; color: var(--muted); margin-top: 1px; }
.page-content { padding: 32px; flex: 1; }

/* ── Stats grid ────────────────────────────────────────── */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 32px;
}
.stat-card {
  background: rgba(255,255,255,.03);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 24px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.stat-card .s-label { font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .08em; font-weight: 600; }
.stat-card .s-value { font-size: 36px; font-weight: 800; letter-spacing: -.05em; line-height: 1; background: linear-gradient(135deg, var(--blue), var(--orange)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.stat-card .s-hint { font-size: 12px; color: var(--muted); }

/* ── Cards ─────────────────────────────────────────────── */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.course-card {
  background: rgba(255,255,255,.03);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform .2s ease, border-color .2s ease;
  cursor: pointer;
  display: flex;
  flex-direction: column;
}
.course-card:hover { transform: translateY(-2px); border-color: var(--line2); }
.course-thumb {
  width: 100%;
  aspect-ratio: 16/9;
  background: var(--bg3);
  object-fit: cover;
  display: block;
}
.course-thumb-placeholder {
  width: 100%;
  aspect-ratio: 16/9;
  background: linear-gradient(135deg, rgba(31,122,255,.1), rgba(255,107,24,.08));
  display: grid;
  place-items: center;
  color: rgba(255,255,255,.2);
}
.course-thumb-placeholder svg { width: 40px; height: 40px; fill: none; stroke: currentColor; stroke-width: 1.5; }
.course-body { padding: 18px; flex: 1; display: flex; flex-direction: column; gap: 8px; }
.course-title { font-size: 16px; font-weight: 700; letter-spacing: -.02em; line-height: 1.3; }
.course-desc { font-size: 13px; color: var(--muted); line-height: 1.6; flex: 1; }
.progress-wrap { margin-top: 4px; }
.progress-label { display: flex; justify-content: space-between; font-size: 11px; color: var(--muted); margin-bottom: 6px; }
.progress-bar { height: 5px; background: rgba(255,255,255,.08); border-radius: 99px; overflow: hidden; }
.progress-fill { height: 100%; background: linear-gradient(90deg, var(--blue), var(--orange)); border-radius: 99px; transition: width .4s ease; }
.course-footer { padding: 12px 18px; border-top: 1px solid var(--line); }
.btn-sm {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 16px; border-radius: 8px; font-size: 13px; font-weight: 600;
  border: none; transition: .15s ease;
}
.btn-primary { background: linear-gradient(135deg, var(--blue), var(--orange)); color: #fff; }
.btn-primary:hover { opacity: .9; transform: translateY(-1px); }
.btn-ghost { background: transparent; border: 1px solid var(--line); color: var(--text); }
.btn-ghost:hover { border-color: var(--line2); background: rgba(255,255,255,.04); }
.btn-danger { background: rgba(239,68,68,.1); border: 1px solid rgba(239,68,68,.2); color: var(--red); }
.btn-danger:hover { background: rgba(239,68,68,.18); }
.btn-success { background: rgba(34,197,94,.1); border: 1px solid rgba(34,197,94,.2); color: var(--green); }
.btn-success:hover { background: rgba(34,197,94,.18); }

/* Full size button */
.btn-full {
  display: flex; align-items: center; justify-content: center; gap: 8px;
  width: 100%; padding: 13px 20px; border-radius: 12px; font-size: 15px; font-weight: 600;
  border: none; cursor: pointer; transition: .2s ease;
}

/* ── Tables ─────────────────────────────────────────────── */
.table-wrap {
  background: rgba(255,255,255,.02);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
table { width: 100%; border-collapse: collapse; }
thead th {
  padding: 12px 16px;
  text-align: left;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--muted);
  background: rgba(255,255,255,.02);
  border-bottom: 1px solid var(--line);
}
tbody td { padding: 14px 16px; font-size: 14px; border-bottom: 1px solid var(--line); vertical-align: middle; }
tbody tr:last-child td { border-bottom: none; }
tbody tr:hover td { background: rgba(255,255,255,.02); }
.badge {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 3px 10px; border-radius: 99px; font-size: 11px; font-weight: 600;
}
.badge-blue { background: rgba(31,122,255,.12); color: #60a5ff; border: 1px solid rgba(31,122,255,.2); }
.badge-orange { background: rgba(255,107,24,.12); color: #fb923c; border: 1px solid rgba(255,107,24,.2); }
.badge-green { background: rgba(34,197,94,.12); color: #4ade80; border: 1px solid rgba(34,197,94,.2); }
.badge-gray { background: rgba(255,255,255,.06); color: var(--muted); border: 1px solid var(--line); }
.actions { display: flex; gap: 6px; }

/* ── Modal ──────────────────────────────────────────────── */
.modal-overlay {
  display: none;
  position: fixed; inset: 0;
  background: rgba(2,7,19,.85);
  backdrop-filter: blur(8px);
  z-index: 500;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.modal-overlay.open { display: flex; }
.modal {
  background: var(--bg2);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 32px;
  width: 100%;
  max-width: 480px;
  position: relative;
}
.modal-title { font-size: 20px; font-weight: 700; letter-spacing: -.03em; margin-bottom: 6px; }
.modal-sub { font-size: 13px; color: var(--muted); margin-bottom: 24px; }
.modal-close {
  position: absolute; top: 16px; right: 16px;
  background: none; border: none;
  color: var(--muted); padding: 6px; border-radius: 8px;
  display: grid; place-items: center;
  transition: color .15s, background .15s;
}
.modal-close:hover { color: #fff; background: rgba(255,255,255,.07); }
.modal-close svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* ── Forms ──────────────────────────────────────────────── */
.form-group { margin-bottom: 16px; }
.form-label { display: block; font-size: 13px; font-weight: 600; color: rgba(255,255,255,.8); margin-bottom: 7px; }
.form-input, .form-select, .form-textarea {
  width: 100%;
  background: rgba(255,255,255,.04);
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 10px;
  padding: 11px 14px;
  font-size: 14px;
  font-family: inherit;
  outline: none;
  transition: border-color .2s, box-shadow .2s;
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
  border-color: rgba(31,122,255,.5);
  box-shadow: 0 0 0 3px rgba(31,122,255,.08);
}
.form-input::placeholder, .form-textarea::placeholder { color: rgba(255,255,255,.3); }
.form-select option { background: var(--bg2); }
.form-textarea { min-height: 90px; resize: vertical; }
.form-hint { font-size: 11px; color: var(--muted); margin-top: 5px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }

/* ── Alerts ─────────────────────────────────────────────── */
.alert { padding: 12px 16px; border-radius: 10px; font-size: 13px; margin-bottom: 16px; display: none; }
.alert.show { display: block; }
.alert-error { background: rgba(239,68,68,.08); border: 1px solid rgba(239,68,68,.2); color: #fca5a5; }
.alert-success { background: rgba(34,197,94,.08); border: 1px solid rgba(34,197,94,.2); color: #86efac; }

/* ── Empty state ────────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--muted);
}
.empty-state svg { width: 48px; height: 48px; fill: none; stroke: currentColor; stroke-width: 1.5; margin-bottom: 16px; opacity: .4; }
.empty-state h3 { font-size: 18px; color: rgba(255,255,255,.7); margin-bottom: 8px; }
.empty-state p { font-size: 14px; }

/* ── Section header ─────────────────────────────────────── */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  gap: 16px;
}
.section-title { font-size: 18px; font-weight: 700; letter-spacing: -.03em; }
.section-sub { font-size: 13px; color: var(--muted); margin-top: 2px; }

/* ── Lesson viewer ──────────────────────────────────────── */
.lesson-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 0;
  min-height: calc(100vh - 64px);
}
.lesson-main { padding: 32px; border-right: 1px solid var(--line); }
.video-wrap {
  aspect-ratio: 16/9;
  background: #000;
  border-radius: 12px;
  overflow: hidden;
  margin-bottom: 24px;
}
.video-wrap iframe { width: 100%; height: 100%; border: 0; }
.lesson-title { font-size: 24px; font-weight: 700; letter-spacing: -.03em; margin-bottom: 8px; }
.lesson-desc { color: var(--muted); font-size: 15px; line-height: 1.7; }
.lesson-actions { display: flex; gap: 12px; margin-top: 24px; flex-wrap: wrap; }

.lesson-sidebar { display: flex; flex-direction: column; }
.lesson-sidebar-header {
  padding: 20px;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.lesson-list { overflow-y: auto; flex: 1; padding: 8px; }
.lesson-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  border-radius: 10px;
  cursor: pointer;
  transition: background .15s;
  margin-bottom: 2px;
}
.lesson-item:hover { background: rgba(255,255,255,.04); }
.lesson-item.active { background: rgba(31,122,255,.1); }
.lesson-item.active .lesson-item-title { color: var(--blue); font-weight: 600; }
.lesson-check {
  width: 24px; height: 24px;
  border-radius: 50%;
  border: 2px solid var(--line);
  display: grid; place-items: center;
  flex-shrink: 0;
  font-size: 11px;
  color: var(--muted);
  background: rgba(255,255,255,.03);
}
.lesson-check.done { background: var(--green); border-color: var(--green); color: #fff; }
.lesson-item-title { font-size: 13px; color: rgba(255,255,255,.8); line-height: 1.3; }
.lesson-item-dur { font-size: 11px; color: var(--muted); margin-top: 2px; }

/* ── Login page ─────────────────────────────────────────── */
.login-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  background:
    radial-gradient(circle at 20% 20%, rgba(31,122,255,.1), transparent 40%),
    radial-gradient(circle at 80% 80%, rgba(255,107,24,.1), transparent 40%),
    var(--bg);
  padding: 20px;
}
.login-card {
  width: 100%;
  max-width: 400px;
  background: rgba(255,255,255,.03);
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: 40px 36px;
}
.login-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 32px;
}
.login-logo svg { width: 36px; height: 36px; }
.login-logo .name { font-size: 22px; font-weight: 700; letter-spacing: -.04em; color: #fff; }
.login-logo .name span { color: var(--orange); }
.login-logo .sub { font-size: 10px; color: rgba(255,255,255,.4); letter-spacing: .06em; text-transform: uppercase; }
.login-title { font-size: 22px; font-weight: 700; letter-spacing: -.03em; margin-bottom: 6px; }
.login-sub { font-size: 14px; color: var(--muted); margin-bottom: 28px; }

/* ── Responsive ─────────────────────────────────────────── */
@media (max-width: 900px) {
  .app-layout { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .lesson-layout { grid-template-columns: 1fr; }
  .lesson-sidebar { border-top: 1px solid var(--line); }
  .stats-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
  .page-content { padding: 20px; }
  .topbar { padding: 16px 20px; }
  .stats-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}