/* ==========================================
   EDU21.AI — ESTILOS GLOBALES
   ========================================== */

/* === VARIABLES === */
:root {
  --purple:       #673de6;
  --purple-light: #8b5cf6;
  --purple-dark:  #4c1d95;
  --orange:       #f97316;
  --orange-light: #fb923c;
  --dark:         #0a0a14;
  --dark-2:       #111125;
  --dark-3:       #1a1a35;
  --dark-4:       #252548;
  --text:         #e2e8f0;
  --text-muted:   #94a3b8;
  --border:       rgba(103, 61, 230, 0.2);
  --white:        #ffffff;
  --radius:       12px;
  --radius-lg:    20px;
  --shadow:       0 4px 24px rgba(103, 61, 230, 0.15);
  --shadow-lg:    0 8px 48px rgba(103, 61, 230, 0.25);
  --transition:   0.3s ease;
}

/* === RESET === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Inter', -apple-system, sans-serif;
  background: var(--dark);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
details { cursor: pointer; }

/* === CONTAINER === */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* === BOTONES === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  transition: all var(--transition);
  border: 2px solid transparent;
  white-space: nowrap;
}
.btn-primary {
  background: var(--purple);
  color: var(--white);
  border-color: var(--purple);
}
.btn-primary:hover {
  background: var(--purple-light);
  border-color: var(--purple-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}
.btn-outline {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}
.btn-outline:hover {
  border-color: var(--purple);
  color: var(--white);
  background: rgba(103, 61, 230, 0.1);
}
.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border-color: transparent;
}
.btn-ghost:hover { color: var(--white); }
.btn-lg { padding: 16px 32px; font-size: 16px; border-radius: 10px; }
.btn-sm { padding: 8px 16px; font-size: 13px; }
.btn-full { width: 100%; }

/* === TIPOGRAFÍA ESPECIAL === */
.gradient-text {
  background: linear-gradient(135deg, var(--purple-light), var(--orange-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-tag {
  display: inline-block;
  background: rgba(103, 61, 230, 0.15);
  color: var(--purple-light);
  border: 1px solid rgba(103, 61, 230, 0.3);
  padding: 4px 14px;
  border-radius: 99px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  margin-bottom: 16px;
}
.section-header {
  text-align: center;
  margin-bottom: 60px;
}
.section-title {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 800;
  line-height: 1.2;
  color: var(--white);
  margin-bottom: 16px;
}
.section-subtitle {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 540px;
  margin: 0 auto;
}

/* ==========================================
   NAVBAR
   ========================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all var(--transition);
  border-bottom: 1px solid transparent;
}
.navbar.scrolled {
  background: rgba(10, 10, 20, 0.92);
  backdrop-filter: blur(20px);
  border-bottom-color: var(--border);
  padding: 12px 0;
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 32px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 22px;
  font-weight: 800;
  color: var(--white);
}
.logo-icon { height: 36px; width: auto; display: block; }
.logo-edu { color: #2563eb; }
.logo-21  { color: #16a34a; }
.logo-ai  { color: #dc2626; }
.nav-links {
  display: flex;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  padding: 8px 14px;
  border-radius: 8px;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition);
}
.nav-links a:hover { color: var(--white); background: rgba(255,255,255,0.06); }
.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  margin-left: auto;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ==========================================
   HERO
   ========================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 140px 0 80px;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.35;
}
.hero-orb-1 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--purple), transparent 70%);
  top: -200px;
  right: -100px;
}
.hero-orb-2 {
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, var(--orange), transparent 70%);
  bottom: -100px;
  left: -100px;
  opacity: 0.2;
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(103, 61, 230, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(103, 61, 230, 0.06) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 80% 80% at 50% 0%, black 40%, transparent 100%);
}
.hero-inner {
  position: relative;
  text-align: center;
  max-width: 860px;
  margin: 0 auto;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(103, 61, 230, 0.12);
  border: 1px solid rgba(103, 61, 230, 0.25);
  color: var(--purple-light);
  padding: 8px 18px;
  border-radius: 99px;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 28px;
}
.badge-dot {
  width: 8px;
  height: 8px;
  background: #22c55e;
  border-radius: 50%;
  box-shadow: 0 0 8px #22c55e;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.6; transform: scale(1.2); }
}
.hero-title {
  font-size: clamp(36px, 6vw, 68px);
  font-weight: 900;
  line-height: 1.1;
  color: var(--white);
  margin-bottom: 24px;
  letter-spacing: -1px;
}
.hero-subtitle {
  font-size: clamp(16px, 2vw, 20px);
  color: var(--text-muted);
  max-width: 580px;
  margin: 0 auto 40px;
  line-height: 1.7;
}
.hero-ctas {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 60px;
}
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 40px;
  flex-wrap: wrap;
  gap: 0;
}
.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0 32px;
}
.stat-number {
  font-size: 28px;
  font-weight: 800;
  color: var(--white);
}
.stat-label {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
}
.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--border);
}

/* ==========================================
   TRUST BAR
   ========================================== */
.trust-bar {
  padding: 48px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: var(--dark-2);
}
.trust-label {
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 24px;
}
.trust-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 40px;
}
.trust-logo {
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 600;
  opacity: 0.6;
  transition: opacity var(--transition);
}
.trust-logo:hover { opacity: 1; }

/* ==========================================
   FOR WHO
   ========================================== */
.for-who {
  padding: 100px 0;
  background: var(--dark);
}
.cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.who-card {
  background: var(--dark-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition);
  position: relative;
}
.who-card:hover {
  border-color: var(--purple);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.who-card--featured {
  background: linear-gradient(135deg, rgba(103, 61, 230, 0.15), rgba(139, 92, 246, 0.08));
  border-color: rgba(103, 61, 230, 0.4);
}
.who-icon {
  font-size: 36px;
  margin-bottom: 16px;
}
.who-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 12px;
}
.who-card p {
  color: var(--text-muted);
  font-size: 15px;
  line-height: 1.7;
}
.featured-badge {
  position: absolute;
  top: -12px;
  right: 20px;
  background: var(--purple);
  color: var(--white);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 99px;
}

/* ==========================================
   COURSES
   ========================================== */
.courses {
  padding: 100px 0;
  background: var(--dark-2);
}
.courses-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}
.course-card {
  background: var(--dark-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  position: relative;
}
.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(103, 61, 230, 0.4);
}
.course-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 10;
  font-size: 12px;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 99px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.course-badge--free {
  background: #22c55e;
  color: var(--white);
}
.course-badge--premium {
  background: var(--orange);
  color: var(--white);
}
.video-wrapper {
  position: relative;
  aspect-ratio: 16 / 9;
  background: var(--dark-4);
  overflow: hidden;
}
.video-wrapper iframe {
  width: 100%;
  height: 100%;
  border: 0;
}
.video-locked {
  position: relative;
}
.course-thumbnail {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: blur(4px) brightness(0.4);
}
.lock-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  z-index: 5;
}
.lock-icon {
  font-size: 36px;
}
.lock-overlay p {
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
  text-align: center;
}
.course-info {
  padding: 24px;
}
.course-tag {
  display: inline-block;
  background: rgba(103, 61, 230, 0.12);
  color: var(--purple-light);
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 99px;
  margin-bottom: 12px;
}
.course-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 10px;
  line-height: 1.3;
}
.course-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 16px;
}
.course-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 20px;
}
.course-meta span {
  font-size: 13px;
  color: var(--text-muted);
}
.courses-cta {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.courses-cta p {
  color: var(--text-muted);
  font-size: 16px;
}

/* ==========================================
   INSTRUCTOR
   ========================================== */
.instructor {
  padding: 100px 0;
  background: var(--dark);
}
.instructor-inner {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 80px;
  align-items: center;
}
.instructor-photo {
  width: 100%;
  aspect-ratio: 3/4;
  object-fit: cover;
  border-radius: var(--radius-lg);
  display: block;
}
.instructor-photo-placeholder {
  aspect-ratio: 3/4;
  background: linear-gradient(135deg, var(--dark-3), var(--dark-4));
  border: 2px dashed var(--border);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 15px;
  font-weight: 500;
  margin-bottom: 20px;
}
.instructor-social {
  display: flex;
  gap: 12px;
}
.social-btn {
  flex: 1;
  text-align: center;
  padding: 10px;
  background: var(--dark-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  transition: all var(--transition);
}
.social-btn:hover {
  border-color: var(--purple);
  color: var(--white);
}
.instructor-bio {
  color: var(--text-muted);
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 16px;
}
.instructor-stats {
  display: flex;
  gap: 32px;
  margin-top: 32px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}
.i-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.i-stat strong {
  font-size: 24px;
  font-weight: 800;
  color: var(--white);
}
.i-stat span {
  font-size: 13px;
  color: var(--text-muted);
}

/* ==========================================
   TESTIMONIALS
   ========================================== */
.testimonials {
  padding: 100px 0;
  background: var(--dark-2);
}
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.testimonial-card {
  background: var(--dark-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: all var(--transition);
}
.testimonial-card:hover {
  border-color: rgba(103, 61, 230, 0.4);
  transform: translateY(-4px);
}
.testimonial-card--featured {
  background: linear-gradient(135deg, rgba(103, 61, 230, 0.12), rgba(139, 92, 246, 0.06));
  border-color: rgba(103, 61, 230, 0.35);
}
.stars {
  color: #f59e0b;
  font-size: 18px;
  letter-spacing: 2px;
  margin-bottom: 16px;
}
.testimonial-text {
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 24px;
  font-style: italic;
}
.testimonial-author {
  display: flex;
  align-items: center;
  gap: 12px;
}
.author-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--purple), var(--purple-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  color: var(--white);
  flex-shrink: 0;
}
.testimonial-author strong {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: var(--white);
}
.testimonial-author span {
  font-size: 12px;
  color: var(--text-muted);
}

/* ==========================================
   PRICING
   ========================================== */
.pricing {
  padding: 100px 0;
  background: var(--dark);
}
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: start;
}
.pricing-card {
  background: var(--dark-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  position: relative;
  transition: all var(--transition);
}
.pricing-card:hover {
  border-color: rgba(103, 61, 230, 0.4);
  transform: translateY(-4px);
}
.pricing-card--featured {
  background: linear-gradient(160deg, rgba(103, 61, 230, 0.18), rgba(139, 92, 246, 0.08));
  border-color: var(--purple);
  box-shadow: var(--shadow-lg);
  transform: scale(1.03);
}
.pricing-card--featured:hover {
  transform: scale(1.03) translateY(-4px);
}
.pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--purple);
  color: var(--white);
  font-size: 12px;
  font-weight: 700;
  padding: 5px 16px;
  border-radius: 99px;
  white-space: nowrap;
}
.pricing-header {
  margin-bottom: 28px;
}
.pricing-header h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 12px;
}
.pricing-price {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin-bottom: 4px;
}
.price-amount {
  font-size: 42px;
  font-weight: 900;
  color: var(--white);
}
.price-period {
  font-size: 15px;
  color: var(--text-muted);
}
.price-saving {
  font-size: 13px;
  color: #22c55e;
  font-weight: 500;
}
.pricing-features {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 28px;
}
.pricing-features li {
  font-size: 14px;
  color: var(--text-muted);
  padding: 0;
}
.feature--yes { color: var(--text); }
.feature--no { opacity: 0.4; }
.pricing-note {
  font-size: 12px;
  color: var(--text-muted);
  text-align: center;
  margin-top: 12px;
}

/* ==========================================
   FAQ
   ========================================== */
.faq {
  padding: 100px 0;
  background: var(--dark-2);
}
.faq-list {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.faq-item {
  background: var(--dark-3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item[open] {
  border-color: rgba(103, 61, 230, 0.4);
}
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 600;
  color: var(--white);
  list-style: none;
  cursor: pointer;
  user-select: none;
}
.faq-question::-webkit-details-marker { display: none; }
.faq-question::after {
  content: '+';
  font-size: 20px;
  color: var(--purple-light);
  transition: transform var(--transition);
  flex-shrink: 0;
}
details[open] .faq-question::after {
  content: '−';
}
.faq-answer {
  padding: 0 24px 20px;
  color: var(--text-muted);
  font-size: 15px;
  line-height: 1.7;
}

/* ==========================================
   FINAL CTA
   ========================================== */
.final-cta {
  padding: 120px 0;
  background: var(--dark);
  overflow: hidden;
}
.final-cta-inner {
  position: relative;
  text-align: center;
  background: linear-gradient(135deg, rgba(103, 61, 230, 0.12), rgba(139, 92, 246, 0.06));
  border: 1px solid rgba(103, 61, 230, 0.25);
  border-radius: 28px;
  padding: 80px 40px;
  overflow: hidden;
}
.final-cta-orb {
  position: absolute;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(103, 61, 230, 0.25), transparent 70%);
  border-radius: 50%;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
}
.final-cta-inner h2 {
  font-size: clamp(32px, 5vw, 54px);
  font-weight: 900;
  color: var(--white);
  margin: 16px 0 24px;
  line-height: 1.15;
}
.final-cta-inner p {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 500px;
  margin: 0 auto 36px;
  line-height: 1.6;
}

/* ==========================================
   FOOTER
   ========================================== */
.footer {
  background: var(--dark-2);
  border-top: 1px solid var(--border);
  padding-top: 80px;
}
.footer-inner {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 80px;
  padding-bottom: 60px;
}
.footer-brand p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
  margin: 16px 0 24px;
  max-width: 260px;
}
.footer-social {
  display: flex;
  gap: 12px;
}
.footer-social a {
  width: 36px;
  height: 36px;
  background: var(--dark-3);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  color: var(--text-muted);
  transition: all var(--transition);
}
.footer-social a:hover {
  border-color: var(--purple);
  color: var(--white);
  background: rgba(103, 61, 230, 0.1);
}
.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}
.footer-col h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--white);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 16px;
}
.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-col a {
  font-size: 14px;
  color: var(--text-muted);
  transition: color var(--transition);
}
.footer-col a:hover { color: var(--white); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding: 24px 0;
}
.footer-bottom p {
  font-size: 13px;
  color: var(--text-muted);
  text-align: center;
}

/* ==========================================
   LIBRO
   ========================================== */
.book-section {
  padding: 100px 0;
  background: var(--dark);
}
.book-inner {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 80px;
  align-items: start;
}
.book-cover-col {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.book-cover-wrap {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.book-glow {
  position: absolute;
  inset: -20px;
  background: radial-gradient(circle at center, rgba(103, 61, 230, 0.4), transparent 70%);
  pointer-events: none;
  z-index: 0;
}
.book-cover-img {
  position: relative;
  z-index: 1;
  width: 100%;
  border-radius: var(--radius-lg);
  box-shadow: 0 24px 60px rgba(0,0,0,0.5), 0 0 40px rgba(103, 61, 230, 0.25);
  transition: transform var(--transition);
}
.book-cover-img:hover { transform: scale(1.02) rotate(-1deg); }
.book-cover-fallback {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  aspect-ratio: 3/4;
  background: linear-gradient(135deg, var(--dark-3), var(--dark-4));
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  font-size: 64px;
  color: var(--text-muted);
  z-index: 1;
  position: relative;
}
.book-cover-fallback p {
  font-size: 16px;
  font-weight: 700;
  color: var(--white);
  text-align: center;
  padding: 0 16px;
}
.book-guarantee {
  display: flex;
  align-items: center;
  gap: 12px;
  background: rgba(34, 197, 94, 0.08);
  border: 1px solid rgba(34, 197, 94, 0.2);
  border-radius: var(--radius);
  padding: 16px;
}
.guarantee-icon { font-size: 24px; flex-shrink: 0; }
.book-guarantee strong {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: #22c55e;
}
.book-guarantee span {
  font-size: 13px;
  color: var(--text-muted);
}
.book-title {
  font-size: clamp(24px, 3vw, 36px);
  font-weight: 800;
  color: var(--white);
  line-height: 1.2;
  margin-bottom: 8px;
}
.book-author {
  font-size: 15px;
  color: var(--text-muted);
  margin-bottom: 20px;
}
.book-author strong { color: var(--purple-light); }
.book-desc {
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 24px;
}
.book-topics {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 32px;
}
.book-topics li {
  font-size: 15px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}
.book-formats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.book-format-card {
  display: flex;
  flex-direction: column;
  background: var(--dark-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  transition: all var(--transition);
  cursor: pointer;
  text-decoration: none;
  color: inherit;
}
.book-format-card:hover {
  border-color: var(--purple);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.book-format--digital {
  border-color: rgba(103, 61, 230, 0.35);
  background: linear-gradient(135deg, rgba(103, 61, 230, 0.1), rgba(139, 92, 246, 0.05));
}
.format-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}
.format-icon { font-size: 28px; }
.format-badge {
  background: var(--orange);
  color: var(--white);
  font-size: 11px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 99px;
}
.format-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 8px;
}
.format-price {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 4px;
}
.format-old {
  font-size: 13px;
  color: var(--text-muted);
  text-decoration: line-through;
}
.format-current {
  font-size: 20px;
  font-weight: 800;
  color: var(--white);
}
.format-note {
  font-size: 12px;
  color: var(--text-muted);
}
.book-cta-btn {
  margin-top: 8px;
  align-self: flex-start;
}

/* Nombre + badge verificado */
.instructor-name-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 8px;
}
.verified-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: linear-gradient(135deg, #0a66c2, #0d7fd6);
  color: var(--white);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 99px;
  letter-spacing: 0.3px;
  flex-shrink: 0;
}
.instructor-headline {
  font-size: 14px;
  color: var(--purple-light);
  font-weight: 500;
  margin-bottom: 20px;
}
.instructor-quote {
  font-size: 15px;
  color: var(--text);
  font-style: italic;
  border-left: 3px solid var(--purple);
  padding-left: 16px;
  margin: 0 0 24px;
  line-height: 1.6;
}

/* Credenciales del instructor */
.instructor-credentials {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}
.credential-tag {
  background: rgba(103, 61, 230, 0.12);
  border: 1px solid rgba(103, 61, 230, 0.25);
  color: var(--purple-light);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 99px;
}

/* Banner del libro en el hero */
.hero-book-banner {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: rgba(249, 115, 22, 0.1);
  border: 1px solid rgba(249, 115, 22, 0.25);
  border-radius: 12px;
  padding: 12px 20px;
  margin-bottom: 32px;
  text-decoration: none;
  transition: all var(--transition);
  cursor: pointer;
}
.hero-book-banner:hover {
  background: rgba(249, 115, 22, 0.18);
  border-color: rgba(249, 115, 22, 0.4);
  transform: translateY(-2px);
}
.hbb-icon { font-size: 28px; }
.hbb-text { text-align: left; }
.hbb-label {
  display: block;
  font-size: 11px;
  font-weight: 700;
  color: var(--orange-light);
  text-transform: uppercase;
  letter-spacing: 0.8px;
}
.hbb-title {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--white);
}
.hbb-arrow {
  font-size: 18px;
  color: var(--orange-light);
  margin-left: 4px;
}

/* ==========================================
   SELECTOR DE MONEDA / REGIÓN
   ========================================== */
.currency-toggle {
  display: inline-flex;
  background: var(--dark-3);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 4px;
  gap: 4px;
  margin-top: 20px;
}
.currency-btn {
  padding: 10px 20px;
  border: none;
  border-radius: 9px;
  background: transparent;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: inherit;
}
.currency-btn.active {
  background: var(--purple);
  color: var(--white);
  box-shadow: 0 2px 12px rgba(103,61,230,0.4);
}
.currency-btn:not(.active):hover {
  color: var(--white);
  background: rgba(255,255,255,0.06);
}
.payment-btns {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ==========================================
   ANIMACIONES DE SCROLL
   ========================================== */
.fade-up {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}
.who-card:nth-child(2) { transition-delay: 0.1s; }
.who-card:nth-child(3) { transition-delay: 0.2s; }
.course-card:nth-child(2) { transition-delay: 0.1s; }
.course-card:nth-child(3) { transition-delay: 0.2s; }
.testimonial-card:nth-child(2) { transition-delay: 0.1s; }
.testimonial-card:nth-child(3) { transition-delay: 0.2s; }
.pricing-card:nth-child(2) { transition-delay: 0.1s; }
.pricing-card:nth-child(3) { transition-delay: 0.2s; }

/* Estilos nav móvil */
.nav-links.mobile-open,
.nav-actions.mobile-open {
  display: flex;
}
@media (max-width: 768px) {
  .nav-links.mobile-open {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(10, 10, 20, 0.98);
    flex-direction: column;
    padding: 24px;
    border-bottom: 1px solid var(--border);
    gap: 4px;
  }
  .nav-links.mobile-open a {
    padding: 14px 16px;
    font-size: 16px;
  }
}

/* ==========================================
   RESPONSIVE
   ========================================== */
@media (max-width: 1024px) {
  .cards-grid,
  .courses-grid,
  .testimonials-grid,
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .instructor-inner,
  .book-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }
  .book-cover-img {
    max-width: 320px;
    margin: 0 auto;
  }
  .instructor-photo-placeholder {
    aspect-ratio: 16/9;
    max-height: 360px;
  }
  .pricing-card--featured {
    transform: scale(1);
  }
}

@media (max-width: 768px) {
  .nav-links,
  .nav-actions .btn-ghost { display: none; }
  .hamburger { display: flex; }
  .nav-actions { gap: 8px; }
  .nav-actions .btn-primary { font-size: 13px; padding: 10px 16px; }

  .hero-stats {
    padding: 20px;
    gap: 0;
  }
  .stat { padding: 12px 16px; }
  .stat-number { font-size: 22px; }

  .cards-grid,
  .courses-grid,
  .testimonials-grid,
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 48px;
  }
  .footer-links {
    grid-template-columns: repeat(2, 1fr);
  }
  .instructor-stats {
    flex-wrap: wrap;
    gap: 20px;
  }
  .hero-ctas {
    flex-direction: column;
    align-items: center;
  }
  .btn-lg { width: 100%; max-width: 360px; }
  .book-formats { grid-template-columns: 1fr; }
  .hero-book-banner { text-align: left; width: 100%; max-width: 420px; }
}

@media (max-width: 480px) {
  .hero-stats {
    flex-direction: column;
  }
  .stat-divider { width: 40px; height: 1px; }
  .footer-links { grid-template-columns: 1fr; }
  .trust-logos { gap: 24px; }
}