/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --blue-dark: #0a0f1e;
  --blue-mid: #0d1b3e;
  --blue-accent: #1a4a8a;
  --blue-bright: #2563eb;
  --cyan: #06b6d4;
  --purple: #7c3aed;
  --gold: #f59e0b;
  --white: #ffffff;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-400: #94a3b8;
  --gray-600: #475569;
  --text: #1e293b;
  --radius: 16px;
  --shadow: 0 20px 60px rgba(0,0,0,0.15);
  --transition: 0.3s cubic-bezier(0.4,0,0.2,1);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Raleway', sans-serif;
  color: var(--text);
  background: var(--white);
  overflow-x: hidden;
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }

/* ===== HEADER ===== */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,15,30,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: var(--transition);
}

.nav {
  display: flex; align-items: center; justify-content: space-between;
  height: 70px;
}

.nav-logo {
  display: flex; align-items: center; gap: 10px;
  color: var(--white); font-weight: 700; font-size: 1rem;
}

.logo-icon { font-size: 1.5rem; }

.nav-links {
  display: flex; align-items: center; gap: 32px;
  list-style: none;
}

.nav-links a {
  color: rgba(255,255,255,0.75);
  font-size: 0.9rem; font-weight: 500;
  transition: color var(--transition);
}

.nav-links a:hover { color: var(--white); }

.nav-buy-btn {
  background: var(--blue-bright) !important;
  color: var(--white) !important;
  padding: 8px 20px;
  border-radius: 8px;
  font-weight: 600 !important;
  transition: background var(--transition) !important;
}

.nav-buy-btn:hover { background: #1d4ed8 !important; }

.burger {
  display: none; flex-direction: column; gap: 5px;
  background: none; border: none; cursor: pointer; padding: 4px;
}

.burger span {
  display: block; width: 24px; height: 2px;
  background: var(--white); border-radius: 2px;
  transition: var(--transition);
}

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  background: linear-gradient(135deg, var(--blue-dark) 0%, var(--blue-mid) 50%, #0f1f4a 100%);
  position: relative; overflow: hidden;
  display: flex; align-items: center;
  padding-top: 70px;
}

.hero-bg {
  position: absolute; inset: 0; pointer-events: none;
  background:
    radial-gradient(circle at 20% 50%, rgba(37,99,235,0.15) 0%, transparent 60%),
    radial-gradient(circle at 80% 20%, rgba(124,58,237,0.12) 0%, transparent 50%),
    radial-gradient(circle at 60% 80%, rgba(6,182,212,0.08) 0%, transparent 40%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  padding: 80px 24px;
}

.hero-badge {
  display: inline-block;
  background: rgba(37,99,235,0.2);
  border: 1px solid rgba(37,99,235,0.4);
  color: #93c5fd;
  font-size: 0.8rem; font-weight: 600;
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 20px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hero-title {
  font-family: 'Montserrat', sans-serif;
  font-size: clamp(3.5rem, 8vw, 7rem);
  font-weight: 900;
  color: var(--white);
  line-height: 1;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: rgba(255,255,255,0.65);
  margin-bottom: 12px;
  line-height: 1.5;
}

.hero-author {
  font-size: 1.3rem;
  font-weight: 700;
  color: #93c5fd;
  margin-bottom: 32px;
  letter-spacing: 0.05em;
}

.hero-meta {
  display: flex; align-items: center; gap: 0;
  margin-bottom: 40px;
}

.meta-item { text-align: center; padding: 0 24px; }
.meta-item:first-child { padding-left: 0; }

.meta-num {
  display: block;
  font-size: 2rem; font-weight: 800;
  color: var(--white);
  line-height: 1;
}

.meta-label {
  font-size: 0.78rem;
  color: rgba(255,255,255,0.5);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.meta-divider {
  width: 1px; height: 40px;
  background: rgba(255,255,255,0.15);
}

.hero-actions {
  display: flex; align-items: center; gap: 16px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex; align-items: center; gap: 10px;
  background: linear-gradient(135deg, var(--blue-bright), #1d4ed8);
  color: var(--white);
  padding: 16px 32px;
  border-radius: 12px;
  font-size: 1rem; font-weight: 700;
  box-shadow: 0 8px 24px rgba(37,99,235,0.4);
  transition: transform var(--transition), box-shadow var(--transition);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(37,99,235,0.5);
}

.btn-secondary {
  display: inline-flex; align-items: center;
  color: rgba(255,255,255,0.75);
  padding: 16px 24px;
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 12px;
  font-size: 0.95rem; font-weight: 500;
  transition: all var(--transition);
}

.btn-secondary:hover {
  border-color: rgba(255,255,255,0.5);
  color: var(--white);
  background: rgba(255,255,255,0.05);
}

/* Book display */
.hero-book { display: flex; justify-content: center; align-items: center; }

.book-wrapper { position: relative; display: inline-block; }

.book-glow {
  position: absolute; inset: -20px;
  background: radial-gradient(circle, rgba(37,99,235,0.3), transparent 70%);
  border-radius: 50%;
  animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.6; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.05); }
}

.book-img {
  width: 100%; max-width: 380px;
  border-radius: 8px;
  box-shadow: 0 40px 80px rgba(0,0,0,0.5), 0 0 0 1px rgba(255,255,255,0.05);
  transition: transform var(--transition);
  animation: float 4s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.book-badge-price {
  position: absolute; top: 20px; right: -20px;
  background: linear-gradient(135deg, var(--gold), #d97706);
  color: var(--white);
  padding: 10px 18px;
  border-radius: 12px;
  font-size: 1.1rem; font-weight: 800;
  box-shadow: 0 8px 20px rgba(245,158,11,0.4);
  transform: rotate(3deg);
}

.hero-scroll {
  position: absolute; bottom: 40px; left: 50%;
  transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: 8px;
  color: rgba(255,255,255,0.4);
  font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase;
}

.scroll-line {
  width: 1px; height: 40px;
  background: linear-gradient(to bottom, transparent, rgba(255,255,255,0.4));
  animation: scrollAnim 2s ease-in-out infinite;
}

@keyframes scrollAnim {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

/* ===== SECTIONS SHARED ===== */
.section { padding: 100px 0; }

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 64px;
}

.section-tag {
  display: inline-block;
  background: rgba(37,99,235,0.08);
  color: var(--blue-bright);
  font-size: 0.78rem; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 16px;
  border: 1px solid rgba(37,99,235,0.15);
}

.section-tag.light {
  background: rgba(255,255,255,0.1);
  color: rgba(255,255,255,0.8);
  border-color: rgba(255,255,255,0.15);
}

.section-title {
  font-family: 'Montserrat', sans-serif;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  color: var(--text);
  line-height: 1.2;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1rem;
  color: var(--gray-600);
  line-height: 1.7;
}

/* ===== FEATURES GRID ===== */
.about-book { background: var(--gray-100); }

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

.feature-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px 28px;
  box-shadow: 0 2px 16px rgba(0,0,0,0.06);
  transition: transform var(--transition), box-shadow var(--transition);
  border: 1px solid var(--gray-200);
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 48px rgba(0,0,0,0.12);
}

.feature-icon { font-size: 2.2rem; margin-bottom: 16px; }

.feature-card h3 {
  font-size: 1.05rem; font-weight: 700;
  color: var(--text); margin-bottom: 10px;
}

.feature-card p { font-size: 0.9rem; color: var(--gray-600); line-height: 1.6; }

/* ===== AUDIENCE ===== */
.audience-section { background: var(--white); }

.audience-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.audience-list {
  list-style: none;
  margin-top: 32px;
  display: flex; flex-direction: column; gap: 24px;
}

.audience-list li {
  display: flex; gap: 16px; align-items: flex-start;
}

.audience-icon { font-size: 1.8rem; flex-shrink: 0; }

.audience-list strong { display: block; font-size: 1rem; font-weight: 700; margin-bottom: 4px; }
.audience-list p { font-size: 0.88rem; color: var(--gray-600); }

.book-pages-stack { position: relative; height: 420px; }

.page-img {
  position: absolute;
  border-radius: 12px;
  box-shadow: var(--shadow);
  object-fit: cover;
}

.page-back {
  width: 280px; height: 360px;
  top: 0; left: 0;
  transform: rotate(-4deg);
  opacity: 0.75;
}

.page-front {
  width: 300px; height: 380px;
  bottom: 0; right: 0;
  transform: rotate(3deg);
}

/* ===== AUTHOR ===== */
.author-section {
  background: linear-gradient(135deg, #f8faff 0%, #eef2ff 100%);
}

.author-inner {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 80px;
  align-items: center;
}

.author-card {
  display: flex; justify-content: center;
}

.author-avatar {
  display: flex; flex-direction: column; align-items: center; gap: 20px;
}

.avatar-placeholder {
  width: 220px; height: 220px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue-accent), var(--blue-bright));
  display: flex; align-items: center; justify-content: center;
  font-size: 3.5rem; font-weight: 900;
  color: var(--white);
  box-shadow: 0 20px 60px rgba(37,99,235,0.3);
  letter-spacing: -0.05em;
}

.author-credentials {
  display: flex; gap: 10px; flex-wrap: wrap; justify-content: center;
}

.author-credentials span {
  background: var(--white);
  border: 1px solid var(--gray-200);
  color: var(--blue-bright);
  font-size: 0.78rem; font-weight: 600;
  padding: 4px 14px; border-radius: 100px;
}

.author-name {
  font-family: 'Montserrat', sans-serif;
  font-size: 2rem; font-weight: 800;
  color: var(--text); margin-bottom: 6px;
  margin-top: 8px;
}

.author-title {
  color: var(--blue-bright);
  font-size: 0.95rem; font-weight: 600;
  margin-bottom: 24px;
}

.author-text p {
  color: var(--gray-600);
  line-height: 1.8;
  margin-bottom: 14px;
  font-size: 0.95rem;
}

.author-stats {
  display: flex; gap: 40px; margin-top: 32px;
  padding-top: 32px;
  border-top: 1px solid var(--gray-200);
}

.stat-num {
  display: block;
  font-size: 2rem; font-weight: 800;
  color: var(--blue-bright);
}

.stat-label {
  font-size: 0.8rem; color: var(--gray-600);
}

/* ===== CONTENTS ===== */
.contents-section { background: var(--white); }

.toc-grid {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 60px;
  align-items: start;
}

.toc-list {
  display: flex; flex-direction: column; gap: 2px;
}

.toc-item {
  display: flex; gap: 16px; align-items: baseline;
  padding: 14px 16px;
  border-radius: 10px;
  transition: background var(--transition);
  cursor: default;
}

.toc-item:hover, .toc-item.active {
  background: #eff6ff;
}

.toc-num {
  font-size: 0.78rem; font-weight: 700;
  color: var(--blue-bright);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
  min-width: 80px;
}

.toc-title {
  font-size: 0.9rem; color: var(--text);
  line-height: 1.4;
}

.preview-gallery { position: sticky; top: 100px; }

.preview-img {
  width: 100%;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 16px;
  object-fit: cover; height: 500px;
}

.preview-thumbs {
  display: flex; gap: 10px;
}

.thumb {
  width: 80px; height: 60px;
  object-fit: cover;
  border-radius: 8px;
  cursor: pointer;
  opacity: 0.6;
  transition: opacity var(--transition), border-color var(--transition);
  border: 2px solid transparent;
}

.thumb:hover { opacity: 0.85; }
.thumb.active { opacity: 1; border-color: var(--blue-bright); }

/* ===== BUY SECTION ===== */
.buy-section {
  background: linear-gradient(135deg, var(--blue-dark) 0%, var(--blue-mid) 100%);
  position: relative; overflow: hidden;
}

.buy-bg {
  position: absolute; inset: 0; pointer-events: none;
  background:
    radial-gradient(circle at 10% 50%, rgba(37,99,235,0.2) 0%, transparent 50%),
    radial-gradient(circle at 90% 20%, rgba(124,58,237,0.15) 0%, transparent 40%);
}

.buy-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 80px;
  align-items: center;
  position: relative; z-index: 1;
}

.buy-title {
  font-family: 'Montserrat', sans-serif;
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 800;
  color: var(--white);
  line-height: 1.2;
  margin-bottom: 32px;
  margin-top: 12px;
}

.buy-features {
  list-style: none;
  display: flex; flex-direction: column; gap: 14px;
  margin-bottom: 40px;
}

.buy-features li {
  display: flex; align-items: center; gap: 12px;
  color: rgba(255,255,255,0.85);
  font-size: 0.95rem;
}

.check-icon {
  width: 24px; height: 24px;
  background: rgba(37,99,235,0.3);
  border: 1px solid rgba(37,99,235,0.5);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  color: #93c5fd;
  font-size: 0.8rem; font-weight: 700;
  flex-shrink: 0;
}

.buy-contacts { display: flex; flex-direction: column; gap: 12px; }

.contact-label {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  margin-bottom: 4px;
}

.contact-link {
  display: inline-flex; align-items: center; gap: 10px;
  color: rgba(255,255,255,0.85);
  font-size: 0.95rem; font-weight: 500;
  padding: 10px 18px;
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 10px;
  transition: all var(--transition);
  max-width: 260px;
}

.contact-link:hover {
  border-color: rgba(255,255,255,0.35);
  background: rgba(255,255,255,0.05);
  color: var(--white);
}

.contact-link.telegram:hover { border-color: #2aabee; color: #2aabee; }

/* Price Card */
.price-card {
  background: var(--white);
  border-radius: 24px;
  padding: 40px 36px;
  text-align: center;
  box-shadow: 0 40px 80px rgba(0,0,0,0.3);
  min-width: 300px;
}

.price-tag {
  font-size: 0.78rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--gray-400);
  margin-bottom: 8px;
}

.price-value {
  font-size: 3.5rem; font-weight: 900;
  color: var(--text);
  line-height: 1;
  margin-bottom: 8px;
}

.price-value span { font-size: 2rem; }

.price-note {
  font-size: 0.85rem; color: var(--gray-400);
  margin-bottom: 16px;
}

.price-delivery {
  font-size: 0.88rem;
  color: var(--blue-bright);
  background: #eff6ff;
  padding: 10px 16px;
  border-radius: 10px;
  margin-bottom: 28px;
  font-weight: 500;
}

.btn-buy-main {
  display: flex; align-items: center; justify-content: center; gap: 10px;
  background: linear-gradient(135deg, var(--blue-bright), #1d4ed8);
  color: var(--white);
  padding: 18px 32px;
  border-radius: 14px;
  font-size: 1.05rem; font-weight: 700;
  width: 100%;
  box-shadow: 0 8px 24px rgba(37,99,235,0.4);
  transition: transform var(--transition), box-shadow var(--transition);
  margin-bottom: 16px;
}

.btn-buy-main:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(37,99,235,0.55);
}

.avito-note {
  display: flex; align-items: center; justify-content: center; gap: 6px;
  font-size: 0.78rem;
  color: var(--gray-400);
}

/* ===== FOOTER ===== */
.footer {
  background: var(--blue-dark);
  padding: 40px 0;
  border-top: 1px solid rgba(255,255,255,0.06);
}

.footer-inner {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 20px;
}

.footer-logo {
  display: flex; align-items: center; gap: 10px;
  color: rgba(255,255,255,0.7);
  font-size: 0.9rem;
}

.footer-links { display: flex; gap: 24px; }

.footer-links a {
  color: rgba(255,255,255,0.5);
  font-size: 0.88rem;
  transition: color var(--transition);
}

.footer-links a:hover { color: var(--white); }

.footer-copy {
  color: rgba(255,255,255,0.3);
  font-size: 0.8rem;
}

/* ===== FLOATING BUTTON ===== */
.floating-btn {
  position: fixed; bottom: 28px; right: 28px; z-index: 99;
  opacity: 0; transform: translateY(20px);
  transition: all var(--transition);
  pointer-events: none;
}

.floating-btn.visible {
  opacity: 1; transform: translateY(0);
  pointer-events: auto;
}

.floating-btn a {
  display: block;
  background: linear-gradient(135deg, var(--blue-bright), #1d4ed8);
  color: var(--white);
  padding: 14px 28px;
  border-radius: 50px;
  font-weight: 700; font-size: 0.95rem;
  box-shadow: 0 8px 24px rgba(37,99,235,0.5);
  transition: transform var(--transition), box-shadow var(--transition);
}

.floating-btn a:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 12px 32px rgba(37,99,235,0.6);
}

/* ===== ANIMATIONS ===== */
[data-aos] {
  opacity: 0; transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos="fade-left"] { transform: translateX(30px); }
[data-aos="fade-right"] { transform: translateX(-30px); }
[data-aos="zoom-in"] { transform: scale(0.9); }

[data-aos].aos-animate {
  opacity: 1; transform: none;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .toc-grid { grid-template-columns: 1fr; }
  .preview-gallery { position: static; }
  .preview-img { height: 300px; }
}

@media (max-width: 768px) {
  .hero-grid { grid-template-columns: 1fr; padding: 60px 24px; gap: 40px; }
  .hero-book { order: -1; }
  .book-img { max-width: 250px; }
  .hero-title { font-size: 4rem; }
  .features-grid { grid-template-columns: 1fr; }
  .audience-inner { grid-template-columns: 1fr; gap: 40px; }
  .author-inner { grid-template-columns: 1fr; gap: 40px; }
  .buy-inner { grid-template-columns: 1fr; gap: 40px; }
  .price-card { min-width: unset; width: 100%; }
  .nav-links { display: none; }
  .burger { display: flex; }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: fixed; top: 70px; left: 0; right: 0;
    background: var(--blue-dark);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
  }
  .author-stats { flex-wrap: wrap; gap: 24px; }
  .footer-inner { flex-direction: column; text-align: center; }
}