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

/* ── Dark Theme (default) ──────────────────────────── */
:root {
  --bg-base:    #0d1117;
  --bg-surface: #161c26;
  --bg-card:    #1c2433;
  --bg-hover:   #232e40;
  --border:     #1e2d42;
  --border-2:   #2a3a52;
  --text-1:     #e8edf5;
  --text-2:     #8a97b0;
  --text-3:     #4a5568;

  --amber:  #f5a623;
  --amber2: #e8922a;
  --teal:   #38bfbf;
  --rose:   #e06c75;
  --green:  #52c99b;

  --shadow: 0 20px 40px rgba(0,0,0,0.4);

  --tag-design-bg: rgba(56,191,191,0.12);
  --tag-tech-bg:   rgba(245,166,35,0.12);
  --tag-data-bg:   rgba(82,201,155,0.12);
  --tag-lead-bg:   rgba(224,108,117,0.12);

  --amber-bg:  rgba(245,166,35,0.1);
  --teal-bg:   rgba(56,191,191,0.1);
  --green-bg:  rgba(82,201,155,0.1);
  --rose-bg:   rgba(224,108,117,0.1);
  --amber-bd:  rgba(245,166,35,0.2);
  --teal-bd:   rgba(56,191,191,0.2);
  --green-bd:  rgba(82,201,155,0.2);
  --rose-bd:   rgba(224,108,117,0.2);
}

/* ── Light Theme ───────────────────────────────────── */
@media (prefers-color-scheme: light) {
  :root {
    --bg-base:    #f5f7fa;
    --bg-surface: #ffffff;
    --bg-card:    #ffffff;
    --bg-hover:   #f0f3f8;
    --border:     #e2e8f0;
    --border-2:   #cbd5e1;
    --text-1:     #0f172a;
    --text-2:     #475569;
    --text-3:     #94a3b8;

    --amber:  #d97706;
    --amber2: #b45309;
    --teal:   #0d9488;
    --rose:   #e11d48;
    --green:  #059669;

    --shadow: 0 20px 40px rgba(0,0,0,0.1);

    --tag-design-bg: rgba(13,148,136,0.08);
    --tag-tech-bg:   rgba(217,119,6,0.08);
    --tag-data-bg:   rgba(5,150,105,0.08);
    --tag-lead-bg:   rgba(225,29,72,0.08);

    --amber-bg:  rgba(217,119,6,0.08);
    --teal-bg:   rgba(13,148,136,0.08);
    --green-bg:  rgba(5,150,105,0.08);
    --rose-bg:   rgba(225,29,72,0.08);
    --amber-bd:  rgba(217,119,6,0.25);
    --teal-bd:   rgba(13,148,136,0.25);
    --green-bd:  rgba(5,150,105,0.25);
    --rose-bd:   rgba(225,29,72,0.25);
  }
}

/* ── Base ──────────────────────────────────────────── */
html { scroll-behavior: smooth; }

body {
  font-family: 'DM Sans', sans-serif;
  background: var(--bg-base);
  color: var(--text-1);
  min-height: 100vh;
  overflow-x: hidden;
  transition: background 0.3s, color 0.3s;
}

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-base); }
::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 3px; }

/* ── Layout ────────────────────────────────────────── */
.app-shell {
  display: grid;
  grid-template-columns: 272px 1fr;
  grid-template-rows: 60px 1fr;
  min-height: 100vh;
}

/* ── Topbar ────────────────────────────────────────── */
.topbar {
  grid-column: 1 / -1;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 28px;
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--border);
}

.brand { display: flex; align-items: center; gap: 10px; }

.brand-icon {
  width: 32px; height: 32px; border-radius: 8px;
  background: linear-gradient(135deg, var(--amber), var(--amber2));
  display: flex; align-items: center; justify-content: center;
  font-size: 16px;
}

.brand-name {
  font-family: 'Playfair Display', serif;
  font-size: 20px; font-weight: 700;
  color: var(--text-1);
}

.brand-name span { color: var(--amber); }

.topbar-right { display: flex; align-items: center; gap: 14px; }

.xp-pill {
  background: var(--bg-hover);
  border: 1px solid var(--border-2);
  border-radius: 20px;
  padding: 4px 14px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px; font-weight: 600;
  color: var(--amber);
  display: flex; align-items: center; gap: 6px;
}

.avatar {
  width: 34px; height: 34px; border-radius: 50%;
  background: linear-gradient(135deg, #2a5298, #3d7bd4);
  display: flex; align-items: center; justify-content: center;
  font-size: 12px; font-weight: 700; color: #fff;
  border: 2px solid var(--border-2);
  cursor: pointer;
}

/* ── Sidebar ───────────────────────────────────────── */
.sidebar {
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  padding: 20px 14px;
  overflow-y: auto;
  position: sticky; top: 60px;
  height: calc(100vh - 60px);
  display: flex; flex-direction: column; gap: 4px;
}

.nav-section-label {
  font-size: 10px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 1.5px;
  color: var(--text-3);
  padding: 10px 10px 4px;
}

.nav-btn {
  display: flex; align-items: center; gap: 11px;
  padding: 10px 12px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: none;
  cursor: pointer;
  font-family: 'DM Sans', sans-serif;
  font-size: 14px; font-weight: 500;
  color: var(--text-2);
  width: 100%; text-align: left;
  transition: all 0.16s ease;
}

.nav-btn:hover { background: var(--bg-hover); color: var(--text-1); }

.nav-btn.active {
  background: var(--amber-bg);
  border-color: var(--amber-bd);
  color: var(--amber);
}

.nav-icon { font-size: 16px; width: 20px; text-align: center; }

.nav-badge {
  margin-left: auto;
  background: var(--amber);
  color: #fff;
  font-size: 10px; font-weight: 700;
  padding: 2px 7px; border-radius: 10px;
}

/* Sidebar progress card */
.sidebar-progress {
  margin-top: auto;
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.sp-title {
  font-size: 10px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 1.2px;
  color: var(--text-3); margin-bottom: 14px;
}

.sp-row {
  display: flex; align-items: center;
  justify-content: space-between;
  margin-bottom: 6px;
}

.sp-label { font-size: 13px; color: var(--text-2); }

.sp-val {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--text-2);
}

.bar-track {
  height: 5px; background: var(--border);
  border-radius: 3px; overflow: hidden;
  margin-bottom: 12px;
}

.bar-fill {
  height: 100%; border-radius: 3px;
  transition: width 0.9s cubic-bezier(0.4,0,0.2,1);
}

.badge-row { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 4px; }

.badge-item {
  font-size: 18px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 4px 7px;
  cursor: default;
  transition: transform 0.15s;
}

.badge-item:hover { transform: scale(1.2); }
.badge-item.locked { filter: grayscale(1) opacity(0.3); }

/* ── Main ──────────────────────────────────────────── */
.main {
  padding: 32px 36px;
  overflow-y: auto;
  height: calc(100vh - 60px);
}

.page-title {
  font-family: 'Playfair Display', serif;
  font-size: 28px; font-weight: 700;
  color: var(--text-1); line-height: 1.2;
}

.page-sub {
  font-size: 14px; color: var(--text-2);
  margin-top: 5px; margin-bottom: 28px;
}

/* ── Dashboard ─────────────────────────────────────── */
.dash-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px; margin-bottom: 22px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 22px;
  animation: fadeUp 0.35s ease both;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.sc-icon { font-size: 22px; margin-bottom: 8px; }

.sc-val {
  font-family: 'Playfair Display', serif;
  font-size: 34px; font-weight: 700;
  line-height: 1; margin-bottom: 4px;
}

.sc-key { font-size: 13px; color: var(--text-2); }

.activity-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 24px;
  margin-bottom: 20px;
  animation: fadeUp 0.4s ease both;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.card-title {
  font-family: 'Playfair Display', serif;
  font-size: 18px; margin-bottom: 16px;
}

.feed-item {
  display: flex; align-items: flex-start; gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.feed-item:last-child { border-bottom: none; }

.feed-dot {
  width: 8px; height: 8px; border-radius: 50%;
  margin-top: 5px; flex-shrink: 0;
}

.feed-text { font-size: 13px; color: var(--text-2); line-height: 1.5; }
.feed-text strong { color: var(--text-1); font-weight: 500; }
.feed-time {
  font-size: 11px; color: var(--text-3);
  margin-top: 2px; font-family: 'JetBrains Mono', monospace;
}

.quiz-review { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 10px; }

.qr-chip {
  border-radius: 8px; padding: 8px 12px; text-align: center;
  min-width: 48px;
}

.qr-q {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px; color: var(--text-3); margin-bottom: 3px;
}

.qr-res { font-size: 14px; }

/* ── Course Library ────────────────────────────────── */
.filter-bar {
  display: flex; align-items: center; gap: 10px;
  flex-wrap: wrap; margin-bottom: 24px;
}

.search-wrap { flex: 1; min-width: 200px; position: relative; }

.search-icon {
  position: absolute; left: 12px; top: 50%;
  transform: translateY(-50%);
  color: var(--text-3); font-size: 14px; pointer-events: none;
}

.search-input {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border-2);
  border-radius: 10px;
  padding: 10px 12px 10px 36px;
  font-family: 'DM Sans', sans-serif;
  font-size: 14px; color: var(--text-1);
  outline: none;
  transition: border-color 0.2s;
}

.search-input::placeholder { color: var(--text-3); }
.search-input:focus { border-color: var(--amber); }

.chip {
  padding: 8px 16px; border-radius: 20px;
  border: 1px solid var(--border-2);
  background: var(--bg-card);
  color: var(--text-2);
  font-family: 'DM Sans', sans-serif;
  font-size: 13px; font-weight: 500;
  cursor: pointer;
  transition: all 0.15s;
}

.chip:hover { border-color: var(--amber); color: var(--text-1); }

.chip.active {
  background: var(--amber-bg);
  border-color: var(--amber-bd);
  color: var(--amber);
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.course-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  overflow: hidden;
  cursor: default;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
  animation: fadeUp 0.4s ease both;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: var(--border-2);
}

.course-banner {
  height: 116px;
  display: flex; align-items: center; justify-content: center;
  font-size: 40px; position: relative;
}

.course-banner::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(to bottom, transparent 40%, rgba(0,0,0,0.15));
}

.course-body { padding: 16px; }

.course-tag {
  font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 1.2px;
  padding: 3px 8px; border-radius: 6px;
  display: inline-block; margin-bottom: 8px;
}

.tag-design { background: var(--tag-design-bg); color: var(--teal); }
.tag-tech   { background: var(--tag-tech-bg);   color: var(--amber); }
.tag-data   { background: var(--tag-data-bg);   color: var(--green); }
.tag-lead   { background: var(--tag-lead-bg);   color: var(--rose); }

.course-title {
  font-family: 'Playfair Display', serif;
  font-size: 16px; font-weight: 700;
  color: var(--text-1); margin-bottom: 6px; line-height: 1.3;
}

.course-desc {
  font-size: 12px; color: var(--text-2);
  line-height: 1.55; margin-bottom: 12px;
}

.course-meta { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 10px; }
.meta-item { font-size: 11px; color: var(--text-3); }

.progress-label {
  display: flex; justify-content: space-between;
  margin-top: 8px; margin-bottom: 4px;
}

.progress-pct {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--text-3);
}

.progress-xp {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--amber);
}

.enroll-btn {
  margin-top: 12px; width: 100%;
  padding: 9px; border-radius: 9px;
  border: none; cursor: pointer;
  font-family: 'DM Sans', sans-serif;
  font-size: 13px; font-weight: 600;
  transition: all 0.15s;
}

.enroll-btn:hover { filter: brightness(1.1); transform: translateY(-1px); }

.btn-enrolled {
  background: var(--green-bg);
  color: var(--green);
  border: 1px solid var(--green-bd) !important;
}

.btn-enroll {
  background: var(--amber-bg);
  color: var(--amber);
  border: 1px solid var(--amber-bd) !important;
}

.empty-state { text-align: center; padding: 60px 20px; color: var(--text-3); }
.empty-icon  { font-size: 44px; margin-bottom: 12px; }
.empty-text  { font-size: 14px; }

/* ── Quiz Engine ───────────────────────────────────── */
.quiz-wrap { max-width: 680px; }

.quiz-header-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 22px; margin-bottom: 18px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.quiz-meta {
  display: flex; justify-content: space-between;
  align-items: center; margin-bottom: 14px;
}

.quiz-topic {
  font-size: 12px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 1px;
  color: var(--teal);
}

.quiz-counter {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px; color: var(--text-2);
}

.question-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 28px; margin-bottom: 14px;
  animation: fadeUp 0.22s ease;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.question-text {
  font-family: 'Playfair Display', serif;
  font-size: 19px; line-height: 1.55;
  color: var(--text-1); margin-bottom: 24px;
}

.option-list { display: flex; flex-direction: column; gap: 10px; }

.option-btn {
  width: 100%; text-align: left;
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 13px 16px;
  font-family: 'DM Sans', sans-serif;
  font-size: 14px; color: var(--text-1);
  cursor: pointer;
  display: flex; align-items: center; gap: 12px;
  transition: all 0.15s;
}

.option-btn:hover:not(:disabled) {
  background: var(--bg-card);
  border-color: var(--amber);
}

.option-btn:disabled { cursor: default; }

.opt-letter {
  width: 26px; height: 26px; border-radius: 7px;
  background: var(--border);
  display: flex; align-items: center; justify-content: center;
  font-size: 11px; font-weight: 700; flex-shrink: 0;
  font-family: 'JetBrains Mono', monospace;
  color: var(--text-2);
}

.opt-correct {
  background: var(--green-bg);
  border-color: var(--green-bd) !important;
  color: var(--green);
}

.opt-wrong {
  background: var(--rose-bg);
  border-color: var(--rose-bd) !important;
  color: var(--rose);
}

.opt-show-correct {
  background: var(--green-bg);
  border-color: var(--green-bd) !important;
  color: var(--green);
  opacity: 0.7;
}

.feedback-box {
  border-radius: 10px; padding: 14px 16px;
  margin-bottom: 14px; font-size: 14px; line-height: 1.55;
  animation: fadeUp 0.2s ease;
}

.fb-correct {
  background: var(--green-bg);
  border: 1px solid var(--green-bd);
  color: var(--green);
}

.fb-wrong {
  background: var(--rose-bg);
  border: 1px solid var(--rose-bd);
  color: var(--rose);
}

.next-btn {
  background: linear-gradient(135deg, var(--amber), var(--amber2));
  color: #fff;
  border: none; border-radius: 10px;
  padding: 12px 28px;
  font-family: 'DM Sans', sans-serif;
  font-size: 14px; font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  letter-spacing: 0.3px;
}

.next-btn:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(0,0,0,0.15); }

/* ── Results Screen ────────────────────────────────── */
.results-screen {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 40px; text-align: center;
  animation: fadeUp 0.4s ease;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.score-ring {
  width: 116px; height: 116px; border-radius: 50%;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  margin: 0 auto 22px;
  border: 4px solid var(--border);
}

.score-num {
  font-family: 'Playfair Display', serif;
  font-size: 34px; font-weight: 700;
}

.score-lbl { font-size: 10px; color: var(--text-3); letter-spacing: 1px; }

.res-title {
  font-family: 'Playfair Display', serif;
  font-size: 24px; margin-bottom: 6px;
}

.res-sub { font-size: 14px; color: var(--text-2); margin-bottom: 26px; }

.res-breakdown {
  display: flex; gap: 16px; justify-content: center;
  margin-bottom: 28px; flex-wrap: wrap;
}

.rb-box {
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 10px; padding: 14px 20px; text-align: center;
}

.rb-val {
  font-family: 'Playfair Display', serif;
  font-size: 22px; font-weight: 700; margin-bottom: 4px;
}

.rb-key {
  font-size: 10px; color: var(--text-3);
  text-transform: uppercase; letter-spacing: 0.8px;
}

/* ── Animation ─────────────────────────────────────── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ────────────────────────────────────── */
@media (max-width: 768px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .main { padding: 20px 16px; }
  .dash-grid { grid-template-columns: 1fr; }
  .course-grid { grid-template-columns: 1fr; }
}