:root {
  --bg: #050807;
  --panel: #0b100e;
  --panel-soft: #101713;
  --text: #f4f7f5;
  --muted: #a1aba5;
  --line: rgba(255,255,255,.1);
  --green: #3cff91;
  --green-deep: #0aaa58;
  --green-soft: rgba(60,255,145,.1);
  --shadow: 0 24px 70px rgba(0,0,0,.5);
  --serif: Georgia, "Times New Roman", serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 82% 4%, rgba(60,255,145,.1), transparent 26rem),
    linear-gradient(180deg, #07100c 0, var(--bg) 32rem);
  color: var(--text);
  font-family: var(--sans);
  line-height: 1.6;
}

a { color: inherit; }

.shell {
  width: min(1140px, calc(100% - 36px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid var(--line);
  background: rgba(5,8,7,.88);
  backdrop-filter: blur(16px);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(60,255,145,.38);
  border-radius: 11px;
  background: linear-gradient(145deg, rgba(60,255,145,.24), rgba(60,255,145,.02));
  color: var(--green);
  font-weight: 800;
  letter-spacing: .05em;
  box-shadow: 0 0 30px rgba(60,255,145,.12);
}

.brand strong,
.brand small { display: block; }

.brand strong {
  font-size: .94rem;
  white-space: nowrap;
}

.brand small {
  color: var(--muted);
  font-size: .68rem;
  letter-spacing: .15em;
  text-transform: uppercase;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 18px;
}

.header-nav > a:not(.button) {
  color: var(--muted);
  font-size: .88rem;
  text-decoration: none;
}

.header-nav > a:not(.button):hover { color: var(--text); }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid var(--green);
  border-radius: 999px;
  background: var(--green);
  color: #021108;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 15px 38px rgba(60,255,145,.19);
  transition: transform .18s ease, box-shadow .18s ease, filter .18s ease;
}

.button:hover {
  transform: translateY(-2px);
  filter: brightness(1.04);
  box-shadow: 0 19px 46px rgba(60,255,145,.28);
}

.button-small {
  min-height: 38px;
  padding: 0 16px;
  font-size: .82rem;
}

.button-wide { width: 100%; }

.button-secondary {
  border-color: rgba(60,255,145,.46);
  background: transparent;
  color: var(--green);
  box-shadow: none;
}

.button-secondary:hover {
  background: rgba(60,255,145,.08);
  box-shadow: none;
}

.button-disabled {
  border-color: #59635d;
  background: #59635d;
  color: #e8ece9;
  cursor: not-allowed;
  box-shadow: none;
}

.button-disabled:hover {
  transform: none;
  filter: none;
  box-shadow: none;
}

.hero { padding: 84px 0 92px; }

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(310px, .75fr);
  align-items: center;
  gap: clamp(48px, 8vw, 96px);
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--green);
  font-size: .74rem;
  font-weight: 800;
  letter-spacing: .16em;
  text-transform: uppercase;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 9px;
}

.eyebrow span {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 16px var(--green);
}

h1,
h2,
h3,
p { text-wrap: pretty; }

h1,
h2 {
  font-family: var(--serif);
  letter-spacing: -.025em;
}

h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(3.25rem, 8vw, 6.8rem);
  font-weight: 500;
  line-height: .92;
}

.hero-lead {
  max-width: 720px;
  margin: 30px 0 0;
  font-size: clamp(1.08rem, 2.2vw, 1.3rem);
  line-height: 1.62;
}

.hero-detail {
  max-width: 700px;
  margin: 18px 0 0;
  color: var(--muted);
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.hero-points div {
  min-width: 122px;
  padding: 12px 15px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255,255,255,.025);
}

.hero-points strong,
.hero-points span { display: block; }

.hero-points strong { font-size: .93rem; }

.hero-points span {
  margin-top: 1px;
  color: var(--muted);
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: .09em;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
  margin-top: 30px;
}

.text-link {
  color: var(--text);
  font-size: .9rem;
  font-weight: 700;
  text-decoration-color: rgba(60,255,145,.45);
  text-underline-offset: 5px;
}

.checkout-note {
  margin: 13px 0 0;
  color: var(--muted);
  font-size: .78rem;
}

.cover-panel {
  position: relative;
  width: min(100%, 390px);
  justify-self: end;
  padding: 22px;
  border: 1px solid rgba(60,255,145,.2);
  border-radius: 24px;
  background: linear-gradient(160deg, rgba(60,255,145,.08), rgba(255,255,255,.025));
  box-shadow: var(--shadow);
}

.cover-glow {
  position: absolute;
  inset: 12% 4% 5%;
  background: rgba(60,255,145,.22);
  filter: blur(70px);
  opacity: .42;
}

.cover-panel img {
  position: relative;
  display: block;
  width: 100%;
  border-radius: 10px;
  box-shadow: 0 22px 60px rgba(0,0,0,.62);
}

.cover-caption {
  position: relative;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 16px;
  color: var(--muted);
  font-size: .78rem;
}

.cover-caption strong { color: var(--text); }

.section { padding: 96px 0; }

.section-dark {
  border-block: 1px solid var(--line);
  background: rgba(0,0,0,.23);
}

.statement-grid,
.audience-grid,
.purchase-card {
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: clamp(38px, 8vw, 100px);
}

h2 {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 4.25rem);
  font-weight: 500;
  line-height: 1.02;
}

.statement-copy p,
.audience-grid > div > p:last-child {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 1.05rem;
}

.section-heading {
  max-width: 780px;
  margin-bottom: 42px;
}

.section-heading.compact { max-width: 680px; }

.section-heading > p:last-child {
  max-width: 680px;
  margin: 20px 0 0;
  color: var(--muted);
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.topic-grid article {
  min-height: 255px;
  padding: 25px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: linear-gradient(145deg, rgba(255,255,255,.036), rgba(255,255,255,.012));
}

.topic-number {
  color: var(--green);
  font-family: var(--serif);
  font-size: .85rem;
}

.topic-grid h3 {
  margin: 45px 0 10px;
  font-family: var(--serif);
  font-size: 1.45rem;
  font-weight: 500;
  line-height: 1.18;
}

.topic-grid p {
  margin: 0;
  color: var(--muted);
  font-size: .9rem;
}

.section-accent {
  border-block: 1px solid rgba(60,255,145,.16);
  background: linear-gradient(135deg, rgba(60,255,145,.09), rgba(60,255,145,.025));
}

.check-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding: 14px 0 14px 34px;
  border-bottom: 1px solid var(--line);
}

.check-list li::before {
  content: "✓";
  position: absolute;
  top: 14px;
  left: 0;
  color: var(--green);
  font-weight: 900;
}

.series-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.series-grid a {
  min-height: 190px;
  display: flex;
  flex-direction: column;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255,255,255,.025);
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease, background .18s ease;
}

.series-grid a:hover {
  transform: translateY(-3px);
  border-color: rgba(60,255,145,.38);
  background: rgba(60,255,145,.05);
}

.series-grid a.current {
  border-color: rgba(60,255,145,.48);
  background: var(--green-soft);
}

.series-grid span {
  color: var(--green);
  font-size: .7rem;
  font-weight: 800;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.series-grid strong {
  margin: 30px 0 8px;
  font-family: var(--serif);
  font-size: 1.35rem;
  font-weight: 500;
  line-height: 1.15;
}

.series-grid small {
  color: var(--muted);
  line-height: 1.5;
}

.purchase-section { padding: 20px 0 100px; }

.purchase-card {
  align-items: center;
  padding: clamp(28px, 6vw, 64px);
  border: 1px solid rgba(60,255,145,.28);
  border-radius: 26px;
  background:
    radial-gradient(circle at 90% 10%, rgba(60,255,145,.16), transparent 21rem),
    var(--panel);
  box-shadow: var(--shadow);
}

.purchase-card > div > p:not(.section-kicker) { color: var(--muted); }

.purchase-card ul {
  margin: 24px 0 0;
  padding-left: 20px;
  color: var(--muted);
}

.edition-options {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.price-box {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(0,0,0,.24);
  text-align: center;
}

.price-box > span,
.price-box > strong,
.price-box > small { display: block; }

.price-box > span {
  color: var(--muted);
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .1em;
}

.price-box > strong {
  margin: 6px 0 0;
  font-family: var(--serif);
  font-size: 4.4rem;
  font-weight: 500;
  line-height: 1;
}

.price-box > small { color: var(--muted); }

.price-box .button { margin-top: 25px; }

.price-box p {
  margin: 10px 0 0;
  color: var(--muted);
  font-size: .72rem;
}

.price-box.is-paperback {
  border-color: rgba(60,255,145,.24);
  background: linear-gradient(160deg, rgba(60,255,145,.07), rgba(0,0,0,.22));
}

.edition-options .price-box > strong {
  font-size: clamp(3.4rem, 5vw, 4.4rem);
}

.faq-section { padding-top: 30px; }

.faq-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.faq-grid details {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 15px;
  background: rgba(255,255,255,.02);
}

.faq-grid summary {
  cursor: pointer;
  font-weight: 750;
}

.faq-grid p {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: .88rem;
}

footer {
  border-top: 1px solid var(--line);
  padding: 50px 0;
  background: rgba(0,0,0,.2);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 28px;
  align-items: start;
}

.footer-inner p {
  margin: 5px 0 0;
  color: var(--muted);
  font-size: .82rem;
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 16px;
}

.footer-inner nav a {
  color: var(--muted);
  font-size: .82rem;
  text-decoration: none;
}

.footer-inner nav a:hover { color: var(--text); }

.copyright { grid-column: 1 / -1; }

@media (max-width: 900px) {
  .hero-grid,
  .statement-grid,
  .audience-grid,
  .purchase-card { grid-template-columns: 1fr; }

  .cover-panel {
    width: min(100%, 430px);
    justify-self: start;
  }

  .topic-grid,
  .series-grid { grid-template-columns: repeat(2, 1fr); }

  .faq-grid { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  .shell { width: min(100% - 24px, 1140px); }

  .site-header { position: static; }

  .header-inner { min-height: 64px; }

  .brand small,
  .header-nav > a:not(.button) { display: none; }

  .button-small { padding-inline: 13px; }

  .hero { padding: 55px 0 68px; }

  h1 { font-size: clamp(3.05rem, 17vw, 4.7rem); }

  .hero-points { display: grid; grid-template-columns: 1fr 1fr; }

  .hero-points div { min-width: 0; }

  .section { padding: 70px 0; }

  .topic-grid,
  .series-grid { grid-template-columns: 1fr; }

  .topic-grid article { min-height: 0; }

  .topic-grid h3 { margin-top: 28px; }

  .purchase-section { padding-bottom: 70px; }

  .purchase-card { padding: 25px 19px; }

  .edition-options { grid-template-columns: 1fr; }

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

  .footer-inner nav { justify-content: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}