:root {
  --ink: #082336;
  --ink-soft: #365161;
  --blue-black: #031521;
  --methylene: #005bc8;
  --methylene-bright: #08b8ff;
  --cyan: #7be8ff;
  --paper: #f5f8fb;
  --paper-warm: #fbf5e8;
  --white: #ffffff;
  --line: rgba(8, 35, 54, 0.13);
  --amber: #d99a2b;
  --danger: #a84232;
  --green: #2b7a65;
  --shadow: 0 24px 70px rgba(3, 21, 33, 0.18);
  --soft-shadow: 0 18px 42px rgba(0, 91, 200, 0.13);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Segoe UI", Arial, sans-serif;
  line-height: 1.6;
  letter-spacing: 0;
}

a {
  color: inherit;
}

h1,
h2,
h3,
p,
li {
  overflow-wrap: anywhere;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 12px 5vw;
  background: rgba(255, 255, 255, 0.9);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  color: var(--white);
  background: linear-gradient(135deg, var(--methylene), var(--blue-black));
  border-radius: 8px;
  box-shadow: 0 10px 24px rgba(0, 91, 200, 0.25);
  font-size: 0.86rem;
}

.nav {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
}

.nav a {
  padding: 10px 12px;
  border-radius: 8px;
  color: var(--ink-soft);
  text-decoration: none;
}

.nav a:hover,
.nav a:focus-visible {
  color: var(--ink);
  background: rgba(0, 91, 200, 0.08);
  outline: none;
}

.nav .nav-cta {
  color: var(--white);
  background: var(--methylene);
  box-shadow: 0 12px 30px rgba(0, 91, 200, 0.25);
}

.hero {
  position: relative;
  min-height: calc(100svh - 72px);
  overflow: hidden;
  isolation: isolate;
  color: var(--white);
  background:
    radial-gradient(circle at 74% 35%, rgba(8, 184, 255, 0.34), transparent 26%),
    radial-gradient(circle at 18% 80%, rgba(217, 154, 43, 0.14), transparent 22%),
    linear-gradient(135deg, #041827 0%, #063757 42%, #005bc8 100%);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(rgba(123, 232, 255, 0.13) 1px, transparent 1px),
    linear-gradient(90deg, rgba(123, 232, 255, 0.13) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(90deg, transparent 0%, #000 22%, #000 100%);
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: -1;
  background: url("assets/hero-ebook-bg.jpg") center / cover no-repeat;
  opacity: 0.32;
  mix-blend-mode: screen;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(320px, 0.95fr) minmax(280px, 440px);
  gap: 6vw;
  align-items: center;
  width: min(1180px, 90vw);
  min-height: calc(100svh - 72px);
  margin: 0 auto;
  padding: 64px 0 72px;
}

.hero-copy {
  max-width: 720px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--amber);
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  color: var(--white);
  font-size: clamp(3.1rem, 7vw, 6.45rem);
  line-height: 0.94;
  letter-spacing: 0;
  overflow-wrap: normal;
  word-break: normal;
}

.hero-subtitle {
  margin: 20px 0 0;
  color: var(--cyan);
  font-size: clamp(1.25rem, 2.2vw, 1.78rem);
  font-weight: 800;
}

.hero-lead {
  max-width: 690px;
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.13rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 13px 20px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-weight: 900;
  text-decoration: none;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease, box-shadow 160ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
}

.button.primary {
  color: var(--white);
  background: linear-gradient(135deg, var(--methylene), #003a9b);
  box-shadow: 0 18px 42px rgba(0, 91, 200, 0.32);
}

.button.primary:hover,
.button.primary:focus-visible {
  background: linear-gradient(135deg, #0878f2, #0047b8);
  outline: 3px solid rgba(123, 232, 255, 0.35);
}

.button.secondary {
  color: var(--white);
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.28);
}

.button.secondary:hover,
.button.secondary:focus-visible {
  border-color: var(--cyan);
  outline: none;
}

.button.wide {
  width: 100%;
}

.hero-note,
.microcopy,
.price-note,
.regular-price {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.hero-note {
  color: rgba(255, 255, 255, 0.76);
}

.hero-card {
  align-self: center;
  border: 1px solid rgba(123, 232, 255, 0.28);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  overflow: hidden;
}

.hero-card img {
  display: block;
  width: 100%;
  max-height: 560px;
  padding: 18px;
  object-fit: contain;
}

.hero-card-footer {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid rgba(123, 232, 255, 0.25);
}

.hero-card-footer span {
  padding: 14px 8px;
  border-right: 1px solid rgba(123, 232, 255, 0.25);
  color: var(--white);
  font-size: 0.9rem;
  font-weight: 800;
  text-align: center;
}

.hero-card-footer span:last-child {
  border-right: 0;
}

.proof-band {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-bottom: 1px solid var(--line);
  background: var(--white);
}

.proof-item {
  min-height: 112px;
  padding: 24px 5vw;
  border-right: 1px solid var(--line);
}

.proof-item:last-child {
  border-right: 0;
}

.proof-item strong {
  display: block;
  color: var(--methylene);
  font-size: 1.35rem;
  line-height: 1.2;
}

.proof-item span {
  display: block;
  margin-top: 6px;
  color: var(--ink-soft);
}

.section {
  padding: 88px 5vw;
}

.section-heading,
.section-copy {
  max-width: 920px;
}

.section h2,
.safety-band h2,
.final-cta h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.08;
  letter-spacing: 0;
}

.intro {
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(300px, 1.1fr);
  gap: 54px;
  background: var(--paper);
}

.intro-text {
  max-width: 720px;
  color: var(--ink-soft);
  font-size: 1.06rem;
}

.content-section {
  background: var(--white);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 40px;
}

.feature-card,
.audience-panel,
.price-panel,
.faq-list details {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.feature-card {
  position: relative;
  min-height: 286px;
  padding: 24px;
  overflow: hidden;
  box-shadow: var(--soft-shadow);
}

.feature-card::after {
  content: "";
  position: absolute;
  right: -42px;
  bottom: -42px;
  width: 122px;
  height: 122px;
  border: 1px solid rgba(8, 184, 255, 0.28);
  border-radius: 50%;
}

.feature-icon {
  display: inline-flex;
  margin-bottom: 34px;
  color: var(--methylene);
  font-weight: 900;
}

.feature-card h3,
.audience-panel h3 {
  margin: 0 0 12px;
  color: var(--ink);
  font-size: 1.25rem;
  line-height: 1.25;
}

.feature-card p,
.audience-panel li {
  color: var(--ink-soft);
}

.molecule-section {
  display: grid;
  grid-template-columns: minmax(280px, 0.82fr) minmax(320px, 1fr);
  gap: 56px;
  align-items: center;
  color: var(--white);
  background:
    linear-gradient(135deg, rgba(3, 21, 33, 0.96), rgba(0, 51, 112, 0.92)),
    url("assets/hero-ebook-bg.jpg") center / cover no-repeat;
}

.molecule-section h2,
.molecule-section p {
  color: var(--white);
}

.molecule-copy p:not(.eyebrow) {
  max-width: 680px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 1.08rem;
}

.molecule-visual {
  position: relative;
  min-height: 310px;
  border: 1px solid rgba(123, 232, 255, 0.25);
  border-radius: 8px;
  background:
    linear-gradient(rgba(123, 232, 255, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(123, 232, 255, 0.1) 1px, transparent 1px),
    radial-gradient(circle at 50% 50%, rgba(8, 184, 255, 0.26), transparent 52%);
  background-size: 34px 34px, 34px 34px, auto;
  box-shadow: inset 0 0 80px rgba(8, 184, 255, 0.16);
}

.molecule-visual::before,
.molecule-visual::after,
.molecule-visual span {
  content: "";
  position: absolute;
  border-radius: 999px;
}

.molecule-visual::before {
  left: 50%;
  top: 50%;
  width: 92px;
  height: 92px;
  background: radial-gradient(circle, var(--cyan), var(--methylene));
  box-shadow: 0 0 42px rgba(8, 184, 255, 0.75);
  transform: translate(-50%, -50%);
}

.molecule-visual::after {
  left: 18%;
  top: 58%;
  width: 64%;
  height: 2px;
  background: rgba(123, 232, 255, 0.52);
  transform: rotate(-17deg);
}

.molecule-visual span {
  width: 42px;
  height: 42px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 0 24px rgba(123, 232, 255, 0.45);
}

.molecule-visual span:nth-child(1) {
  left: 18%;
  top: 34%;
}

.molecule-visual span:nth-child(2) {
  right: 17%;
  top: 24%;
}

.molecule-visual span:nth-child(3) {
  left: 24%;
  bottom: 24%;
}

.molecule-visual span:nth-child(4) {
  right: 22%;
  bottom: 22%;
}

.audience-section {
  background: #eef6f7;
}

.audience-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin-top: 40px;
}

.audience-panel {
  padding: 28px;
  box-shadow: var(--soft-shadow);
}

.audience-panel.positive {
  border-top: 5px solid var(--green);
}

.audience-panel.caution {
  border-top: 5px solid var(--danger);
}

.audience-panel ul,
.purchase-list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding-left: 20px;
}

.safety-band {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 48px;
  padding: 76px 5vw;
  color: var(--white);
  background:
    linear-gradient(120deg, rgba(3, 21, 33, 0.98), rgba(0, 64, 150, 0.95)),
    url("assets/hero-ebook-bg.jpg") center / cover no-repeat;
}

.safety-band .eyebrow {
  color: #ffd17c;
}

.safety-band h2,
.safety-band p {
  color: var(--white);
}

.safety-band p {
  margin: 0;
  font-size: 1.08rem;
}

.chapter-list {
  margin-top: 40px;
  border-top: 1px solid var(--line);
}

.chapter-row {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 24px;
  align-items: start;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.chapter-row span {
  color: var(--methylene);
  font-weight: 900;
}

.chapter-row p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 1.06rem;
}

.purchase-section {
  display: grid;
  grid-template-columns: minmax(280px, 0.95fr) minmax(320px, 480px);
  gap: 52px;
  align-items: center;
  background:
    linear-gradient(rgba(0, 91, 200, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 91, 200, 0.05) 1px, transparent 1px),
    var(--paper-warm);
  background-size: 34px 34px;
}

.purchase-copy p:not(.eyebrow) {
  max-width: 680px;
  color: var(--ink-soft);
  font-size: 1.08rem;
}

.purchase-list {
  max-width: 680px;
  margin-top: 22px;
  color: var(--ink-soft);
}

.price-panel {
  overflow: hidden;
  box-shadow: var(--shadow);
}

.price-panel img {
  display: block;
  width: 100%;
  max-height: 560px;
  object-fit: contain;
  object-position: center;
  padding: 22px;
  background:
    radial-gradient(circle at 50% 34%, rgba(8, 184, 255, 0.2), transparent 48%),
    linear-gradient(135deg, #e9f8ff, #f8f0df);
}

.price-content {
  padding: 26px;
}

.regular-price {
  margin: 0;
  text-decoration: none;
}

.launch-price {
  margin: 4px 0 0;
  color: var(--ink);
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1;
}

.faq-section {
  background: var(--paper);
}

.faq-list {
  display: grid;
  gap: 12px;
  max-width: 920px;
  margin-top: 36px;
}

.faq-list details {
  padding: 0;
  box-shadow: 0 10px 28px rgba(3, 21, 33, 0.06);
}

.faq-list summary {
  cursor: pointer;
  padding: 18px 22px;
  color: var(--ink);
  font-weight: 900;
}

.faq-list p {
  margin: 0;
  padding: 0 22px 20px;
  color: var(--ink-soft);
}

.final-cta {
  display: grid;
  justify-items: center;
  gap: 22px;
  padding: 82px 5vw;
  color: var(--white);
  text-align: center;
  background:
    radial-gradient(circle at 50% 10%, rgba(123, 232, 255, 0.28), transparent 34%),
    linear-gradient(135deg, var(--blue-black), #003a9b);
}

.final-cta h2 {
  max-width: 840px;
  color: var(--white);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 28px 5vw;
  color: #dce8e8;
  background: var(--blue-black);
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: var(--cyan);
}

@media (max-width: 1060px) {
  .hero-inner,
  .intro,
  .molecule-section,
  .safety-band,
  .purchase-section {
    grid-template-columns: 1fr;
  }

  .hero-inner {
    gap: 36px;
  }

  .hero-card {
    max-width: 420px;
  }

  .feature-grid,
  .proof-band {
    grid-template-columns: repeat(2, 1fr);
  }

  .feature-card {
    min-height: 230px;
  }
}

@media (max-width: 760px) {
  .site-header {
    position: static;
    align-items: flex-start;
    flex-direction: column;
  }

  .nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .nav a {
    white-space: nowrap;
  }

  .hero {
    min-height: auto;
  }

  .hero-inner {
    width: min(100% - 32px, 560px);
    min-height: auto;
    padding: 52px 0 58px;
  }

  .hero-card {
    max-width: 360px;
  }

  .section {
    padding: 64px 5vw;
  }

  .feature-grid,
  .proof-band,
  .audience-grid {
    grid-template-columns: 1fr;
  }

  .proof-item {
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .proof-item:last-child {
    border-bottom: 0;
  }

  .molecule-visual {
    min-height: 250px;
  }

  .chapter-row {
    grid-template-columns: 48px 1fr;
    gap: 14px;
  }

  .site-footer {
    flex-direction: column;
  }
}

@media (max-width: 460px) {
  .brand span:last-child {
    max-width: 210px;
    white-space: normal;
    line-height: 1.2;
  }

  .hero-actions {
    display: grid;
  }

  .button {
    width: 100%;
  }

  .hero-card-footer {
    grid-template-columns: 1fr;
  }

  .hero-card-footer span {
    border-right: 0;
    border-bottom: 1px solid rgba(123, 232, 255, 0.25);
  }

  .hero-card-footer span:last-child {
    border-bottom: 0;
  }
}