/* ============================================================
   Education 4.0 for Educators — Shared Design System
   Apple-inspired dark design | Dr. Marie Martin
   ============================================================ */

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

/* --- Root Tokens --- */
:root {
  --bg:             #000000;
  --surface:        #1d1d1f;
  --surface-2:      #2a2a2e;
  --surface-3:      #3a3a3e;
  --text-primary:   #f5f5f7;
  --text-secondary: #86868b;
  --accent:         #2997FF;
  --accent-hover:   #4aa8ff;
  --accent-dim:     rgba(41, 151, 255, 0.12);
  --accent-border:  rgba(41, 151, 255, 0.30);
  --border:         rgba(255,255,255,0.08);
  --border-light:   rgba(255,255,255,0.04);
  --radius:         18px;
  --radius-sm:      10px;
  --radius-xs:      6px;
  --shadow:         0 4px 24px rgba(0,0,0,0.5);
  --shadow-lg:      0 12px 48px rgba(0,0,0,0.7);
  --transition:     0.25s ease;
  --font: -apple-system, 'SF Pro Display', 'Inter', sans-serif;
  --max-w: 1120px;
}

/* --- Base --- */
html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background-color: var(--bg);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.65;
  min-height: 100vh;
}

img { max-width: 100%; display: block; }

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover { color: var(--accent-hover); }

ul { list-style: none; }

/* --- Typography Scale --- */
h1, h2, h3, h4, h5 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h1 { font-size: clamp(2.4rem, 6vw, 4rem); }
h2 { font-size: clamp(1.8rem, 4vw, 2.8rem); }
h3 { font-size: clamp(1.3rem, 2.5vw, 1.7rem); }
h4 { font-size: 1.2rem; }
h5 { font-size: 1rem; }

p { color: var(--text-secondary); }
p + p { margin-top: 1rem; }

.eyebrow {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
  display: block;
}

.lead {
  font-size: 1.2rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 680px;
}

/* --- Layout Utilities --- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: 96px 0; }
.section--sm { padding: 64px 0; }
.section--dark { background: var(--surface); }

.section--accent {
  background: linear-gradient(135deg, #0a1628 0%, #001a3a 100%);
  border-top: 1px solid var(--accent-border);
  border-bottom: 1px solid var(--accent-border);
}

.text-center { text-align: center; }
.text-accent  { color: var(--accent); }

.section-header {
  margin-bottom: 56px;
  text-align: center;
}
.section-header p {
  max-width: 640px;
  margin: 1rem auto 0;
  font-size: 1.1rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* --- Card Component --- */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 32px;
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(255,255,255,0.14);
}

.card--accent {
  border-color: var(--accent-border);
  background: linear-gradient(135deg, var(--surface) 0%, #0d1a2e 100%);
}

.card--link {
  cursor: pointer;
  display: block;
  text-decoration: none;
  color: inherit;
}
.card--link:hover h3 { color: var(--accent); }

.card-icon {
  font-size: 2.2rem;
  margin-bottom: 18px;
  display: block;
  line-height: 1;
}

.card h3 { margin-bottom: 12px; transition: color var(--transition); }
.card p  { font-size: 0.97rem; line-height: 1.65; }

.card-meta {
  display: flex;
  gap: 16px;
  margin-top: 20px;
  flex-wrap: wrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: 20px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.04em;
}

/* --- Button Styles --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 980px;
  font-size: 0.97rem;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
  letter-spacing: -0.01em;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: scale(1.03);
  box-shadow: 0 0 24px rgba(41, 151, 255, 0.4);
}

.btn-secondary {
  background: transparent;
  color: var(--accent);
  border: 1.5px solid var(--accent);
}
.btn-secondary:hover {
  background: var(--accent-dim);
  color: var(--accent-hover);
  transform: scale(1.03);
}

.btn-ghost {
  background: var(--surface-2);
  color: var(--text-primary);
  border: 1px solid var(--border);
}
.btn-ghost:hover {
  background: var(--surface-3);
  color: var(--text-primary);
}

.btn-sm { padding: 10px 20px; font-size: 0.875rem; }

/* --- Site Navigation --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(0, 0, 0, 0.82);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border);
}

.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-logo {
  font-size: 0.97rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.01em;
}
.nav-logo span { color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links a {
  font-size: 0.87rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
}
.nav-links a:hover { color: var(--text-primary); }
.nav-cta { color: var(--accent) !important; font-weight: 600 !important; }

/* --- Progress Bar (Course pages) --- */
.progress-wrapper {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 14px 0;
  position: sticky;
  top: 56px;
  z-index: 90;
}

.progress-inner {
  display: flex;
  align-items: center;
  gap: 16px;
}

.progress-label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
  min-width: 100px;
}

.progress-bar-track {
  flex: 1;
  height: 5px;
  background: var(--surface-3);
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #64b5f6);
  border-radius: 3px;
  transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.progress-pct {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent);
  min-width: 36px;
  text-align: right;
}

/* --- Section Tabs (Course navigation) --- */
.section-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.section-tabs::-webkit-scrollbar { display: none; }

.tab-btn {
  padding: 14px 20px;
  background: none;
  border: none;
  border-bottom: 2.5px solid transparent;
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
  flex-shrink: 0;
}
.tab-btn:hover { color: var(--text-primary); }
.tab-btn.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

/* --- Course Content Panels --- */
.course-body {
  max-width: 860px;
  margin: 0 auto;
  padding: 56px 24px 80px;
}

.course-section {
  display: none;
  animation: fadeIn 0.35s ease;
}
.course-section.active { display: block; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

.section-title { font-size: clamp(1.6rem, 4vw, 2.2rem); margin-bottom: 8px; }
.section-intro {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
  line-height: 1.7;
}

/* --- Timeline --- */
.timeline {
  position: relative;
  padding-left: 40px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 14px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), transparent);
}

.timeline-item {
  position: relative;
  margin-bottom: 32px;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -32px;
  top: 7px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg);
  box-shadow: 0 0 0 2px var(--accent);
}

.timeline-date {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
}

.timeline-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 22px 24px;
}
.timeline-card h4 { margin-bottom: 8px; }
.timeline-card p  { font-size: 0.95rem; }

/* --- Checklist Styles --- */
.checklist { display: flex; flex-direction: column; gap: 14px; }

.checklist-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 18px 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
}
.checklist-item:hover { border-color: var(--accent-border); }

.checklist-item input[type="checkbox"] {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  accent-color: var(--accent);
  cursor: pointer;
  margin-top: 2px;
}

.checklist-item label {
  font-size: 0.97rem;
  line-height: 1.5;
  cursor: pointer;
  color: var(--text-primary);
}

.checklist-item.checked {
  background: var(--accent-dim);
  border-color: var(--accent-border);
}
.checklist-item.checked label {
  color: var(--text-secondary);
  text-decoration: line-through;
}

/* --- Reflection Textarea --- */
.reflection-area {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 20px;
  margin-top: 24px;
}

.reflection-area label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.reflection-area textarea {
  width: 100%;
  min-height: 140px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 0.97rem;
  padding: 14px 16px;
  resize: vertical;
  transition: border-color var(--transition);
  outline: none;
  line-height: 1.6;
}
.reflection-area textarea:focus { border-color: var(--accent); }
.reflection-area textarea::placeholder { color: var(--surface-3); }

/* --- Tool Cards (Course 2) --- */
.tool-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: all var(--transition);
}
.tool-card:hover {
  border-color: var(--accent-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

.tool-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.tool-icon { font-size: 1.8rem; line-height: 1; }
.tool-name { font-weight: 700; font-size: 1.05rem; color: var(--text-primary); }
.tool-desc { font-size: 0.93rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: 12px; }
.tool-use  { font-size: 0.85rem; font-weight: 600; color: var(--accent); display: flex; align-items: center; gap: 6px; }

/* --- Framework Steps --- */
.step-card {
  display: flex;
  gap: 24px;
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 20px;
  align-items: flex-start;
  transition: border-color var(--transition);
}
.step-card:hover { border-color: var(--accent-border); }

.step-number {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-weight: 800;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-content h4 { margin-bottom: 8px; font-size: 1.1rem; }
.step-content p  { font-size: 0.95rem; }

/* --- Sample Lesson Snippet --- */
.lesson-snippet {
  background: var(--surface-2);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 24px 28px;
  margin-top: 28px;
}

.lesson-snippet .snippet-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 12px;
}

.lesson-snippet table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.93rem;
}

.lesson-snippet th {
  text-align: left;
  padding: 8px 12px;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border-bottom: 1px solid var(--border);
}

.lesson-snippet td {
  padding: 10px 12px;
  color: var(--text-primary);
  border-bottom: 1px solid var(--border-light);
  vertical-align: top;
}

.lesson-snippet tr:last-child td { border-bottom: none; }

/* --- Course Navigation Buttons --- */
.course-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
  gap: 16px;
  flex-wrap: wrap;
}

.course-nav-center {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* --- Info Box --- */
.info-box {
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  margin: 24px 0;
}
.info-box p { color: var(--text-primary); font-size: 0.95rem; }

/* --- Hero (Landing) --- */
.hero {
  min-height: 92vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse 80% 60% at 50% 20%, rgba(41,151,255,0.10) 0%, transparent 70%),
    #000;
}

.hero::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 80% at 80% 50%, rgba(41,151,255,0.05) 0%, transparent 70%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(2.8rem, 7vw, 5rem);
  letter-spacing: -0.035em;
  line-height: 1.08;
  margin-bottom: 20px;
}

.hero h1 .accent-line {
  display: block;
  color: var(--accent);
  background: linear-gradient(135deg, #2997FF, #64b5f6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: 1.25rem;
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 600px;
  margin-bottom: 40px;
}

/* --- Divider --- */
.divider { height: 1px; background: var(--border); margin: 0; }

/* --- Consulting CTA Strip --- */
.cta-strip {
  background: var(--surface);
  border-top: 1px solid var(--accent-border);
  border-bottom: 1px solid var(--accent-border);
  padding: 72px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-strip::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 100% at 50% 50%, rgba(41,151,255,0.07) 0%, transparent 70%);
  pointer-events: none;
}

.cta-strip h2 { max-width: 680px; margin: 0 auto 16px; }
.cta-strip p  { max-width: 520px; margin: 0 auto 32px; font-size: 1.05rem; }

/* --- Footer --- */
.site-footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copy { font-size: 0.85rem; color: var(--text-secondary); }

.footer-links { display: flex; gap: 24px; }
.footer-links a { font-size: 0.85rem; color: var(--text-secondary); transition: color var(--transition); }
.footer-links a:hover { color: var(--text-primary); }

/* --- About Section --- */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}

.about-content h2 { margin-bottom: 20px; }
.about-content p  { font-size: 1.05rem; line-height: 1.75; margin-bottom: 16px; }

.about-stat-row { display: flex; gap: 32px; margin-top: 28px; flex-wrap: wrap; }

.about-stat { text-align: left; }
.about-stat .stat-num   { font-size: 2rem; font-weight: 700; color: var(--accent); line-height: 1; }
.about-stat .stat-label { font-size: 0.85rem; color: var(--text-secondary); margin-top: 4px; }

.about-visual {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  text-align: center;
}

.about-visual .initials {
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), #0061c2);
  color: #fff;
  font-size: 2rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
}

.about-visual h3 { margin-bottom: 6px; }
.about-visual .title-tag { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 20px; }

.tag-row { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; }
.tag {
  padding: 5px 12px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* --- Completion Banner --- */
.completion-banner {
  background: linear-gradient(135deg, #00382a, #003d2a);
  border: 1px solid rgba(52, 199, 89, 0.3);
  border-radius: var(--radius);
  padding: 28px 32px;
  display: flex;
  align-items: center;
  gap: 20px;
  margin-top: 32px;
}

.completion-icon { font-size: 2.2rem; line-height: 1; flex-shrink: 0; }
.completion-text h4 { color: #30d158; margin-bottom: 4px; }
.completion-text p  { font-size: 0.93rem; color: rgba(255,255,255,0.6); }

/* --- Myth vs Reality Table --- */
.myth-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 20px;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.myth-table th { padding: 14px 20px; font-size: 0.85rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; }
.myth-table th:first-child { background: rgba(255, 69, 58, 0.15); color: #ff6b6b; border-bottom: 1px solid rgba(255, 69, 58, 0.2); }
.myth-table th:last-child  { background: rgba(52, 199, 89, 0.12); color: #30d158;  border-bottom: 1px solid rgba(52, 199, 89, 0.2); }

.myth-table td { padding: 14px 20px; font-size: 0.93rem; vertical-align: top; border-bottom: 1px solid var(--border-light); }
.myth-table td:first-child { background: rgba(255, 69, 58, 0.05); color: var(--text-secondary); }
.myth-table td:last-child  { background: rgba(52, 199, 89, 0.04); color: var(--text-primary); }
.myth-table tr:last-child td { border-bottom: none; }

/* ============================================================
   Responsive Breakpoints
   ============================================================ */

@media (max-width: 900px) {
  .grid-3 { grid-template-columns: 1fr 1fr; }
  .about-grid { grid-template-columns: 1fr; gap: 36px; }
}

@media (max-width: 640px) {
  .section { padding: 64px 0; }
  .section--sm { padding: 48px 0; }
  .container { padding: 0 20px; }

  .grid-3,
  .grid-2 { grid-template-columns: 1fr; }

  .hero { min-height: 88vh; }
  .nav-links { display: none; }

  .course-nav { flex-direction: column; align-items: stretch; }
  .course-nav .btn { justify-content: center; }

  .step-card { flex-direction: column; gap: 16px; }

  .footer-inner { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }

  .tab-btn { padding: 12px 14px; font-size: 0.8rem; }

  .myth-table { font-size: 0.85rem; }
  .myth-table td,
  .myth-table th { padding: 10px 14px; }

  .completion-banner { flex-direction: column; text-align: center; }
  .about-stat-row { justify-content: center; }
}