:root {
  --ink: #102f31;
  --teal: #2f7f7a;
  --teal-dark: #145d5b;
  --rust: #c84a18;
  --sand: #f4ead8;
  --paper: #fffaf1;
  --line: #d8cdbb;
  --muted: #6a6a62;
  --white: #fffef9;
  --shadow: 0 24px 60px rgba(29, 52, 52, .14);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding: 1rem clamp(1.2rem, 4vw, 4.5rem);
  background: rgba(255, 250, 241, .93);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(16, 47, 49, .12);
}

.brand img { width: 148px; height: auto; }
.site-header nav { display: flex; flex-wrap: wrap; gap: 1.3rem; }
.site-header nav a {
  font-size: .84rem;
  font-weight: 800;
  letter-spacing: .08em;
  text-transform: uppercase;
  text-decoration: none;
}

main { overflow: hidden; }
section { padding: clamp(4rem, 8vw, 7rem) clamp(1.2rem, 6vw, 6rem); }

.hero {
  min-height: 76vh;
  display: grid;
  grid-template-columns: 1.05fr .95fr;
  align-items: center;
  gap: clamp(2rem, 6vw, 6rem);
  background: linear-gradient(135deg, #fffaf1 0%, #f3e6ce 100%);
}
.hero-copy { max-width: 700px; }
.eyebrow, .status {
  margin: 0 0 .7rem;
  color: var(--teal-dark);
  font-size: .78rem;
  font-weight: 900;
  letter-spacing: .13em;
  text-transform: uppercase;
}
h1, h2, h3 { line-height: 1.05; margin: 0; }
h1 { font-size: clamp(3.5rem, 8vw, 7.4rem); letter-spacing: -.055em; }
h2 { font-size: clamp(2.3rem, 5vw, 4.8rem); letter-spacing: -.04em; }
h3 { font-size: clamp(2rem, 4vw, 3.4rem); letter-spacing: -.035em; }
.lede { max-width: 640px; font-size: clamp(1.15rem, 2vw, 1.45rem); margin: 1.5rem 0 0; }
.actions, .purchase-row { display: flex; gap: .9rem; flex-wrap: wrap; margin-top: 2rem; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: .9rem 1.3rem;
  border: 1px solid var(--ink);
  text-decoration: none;
  font-weight: 850;
  border-radius: 999px;
}
.button.primary { background: var(--ink); color: var(--white); }
.button.secondary { background: transparent; }

.hero-logo-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: clamp(1rem, 3vw, 2rem);
}
.hero-logo {
  width: min(100%, 560px);
  height: auto;
  filter: drop-shadow(0 24px 40px rgba(16, 47, 49, .12));
}

.books-section { background: var(--white); }
.section-heading { max-width: 900px; margin-bottom: clamp(2.5rem, 5vw, 4.5rem); }
.section-heading.narrow { max-width: 820px; }
.section-heading p:last-child { font-size: 1.15rem; }
.book-grid {
  display: grid;
  grid-template-columns: minmax(260px, 430px) 1fr;
  align-items: center;
  gap: clamp(2.5rem, 7vw, 7rem);
}
.cover-wrap { max-width: 430px; }
.real-cover { width: 100%; border-radius: 4px; box-shadow: var(--shadow); }
.book-copy { max-width: 760px; }
.book-copy .subtitle, .climate-card .subtitle { font-size: 1.15rem; font-weight: 800; color: var(--rust); margin: .55rem 0 1.4rem; }
.book-copy p:not(.status):not(.subtitle) { font-size: 1.08rem; }

.climate-card {
  margin-top: clamp(4rem, 8vw, 7rem);
  padding: clamp(2rem, 4vw, 3.4rem);
  border: 1px solid var(--line);
  border-radius: 28px;
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: 2.5rem;
  background: var(--sand);
}
.climate-card > p { margin: 0; font-size: 1.15rem; align-self: end; }

.sample-section { background: #eef3ee; }
.sample-reader { max-width: 900px; border-top: 1px solid rgba(16,47,49,.25); border-bottom: 1px solid rgba(16,47,49,.25); }
.sample-reader summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 0;
  font-weight: 900;
  font-size: 1.05rem;
}
.sample-reader summary::-webkit-details-marker { display: none; }
.chapter-text { padding: .7rem 0 2.2rem; max-width: 760px; }
.chapter-text p { font-family: Georgia, "Times New Roman", serif; font-size: 1.18rem; line-height: 1.8; }
.sample-subhead {
  font-size: 1.35rem;
  letter-spacing: -.02em;
  margin: .6rem 0 1rem;
}
.sample-subhead.chapter-break {
  margin-top: 2.4rem;
  padding-top: 1.6rem;
  border-top: 1px solid rgba(16,47,49,.18);
}

.about-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(2rem, 7vw, 7rem);
  background: var(--paper);
}
.about-copy { max-width: 680px; font-size: 1.14rem; }
.about-copy p:first-child { font-size: 1.35rem; font-weight: 750; }

.newsletter { background: var(--ink); color: var(--white); }
.newsletter .eyebrow { color: #82c2b8; }
.newsletter h2 { max-width: 900px; }
.newsletter form { display: flex; gap: .8rem; max-width: 680px; margin-top: 2rem; }
.newsletter input { flex: 1; min-width: 0; border-radius: 999px; border: 0; padding: 1rem 1.2rem; font: inherit; }
.newsletter .button.primary { background: var(--rust); border-color: var(--rust); cursor: pointer; }

footer {
  padding: 2rem clamp(1.2rem, 6vw, 6rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  background: #0a2426;
  color: #e9efe9;
}
.footer-brand {
  background: #fffaf1;
  border-radius: 999px;
  padding: .6rem 1rem;
}
.footer-brand img { width: 130px; }
.footer-links { display: flex; gap: 1.5rem; flex-wrap: wrap; align-items: center; }
.footer-links a { text-decoration: none; }

@media (max-width: 850px) {
  .site-header { align-items: flex-start; }
  .site-header nav { gap: .75rem 1rem; justify-content: flex-end; }
  .hero, .book-grid, .climate-card, .about-section { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .hero-logo { max-width: 420px; }
  .cover-wrap { max-width: 360px; margin-inline: auto; }
  .climate-card { gap: 1rem; }
  footer { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 580px) {
  .site-header { position: static; flex-direction: column; }
  .site-header nav { justify-content: flex-start; }
  .newsletter form { flex-direction: column; }
  h1 { font-size: clamp(3.2rem, 18vw, 5.2rem); }
}