:root {
  --ink: #17496b;
  --teal: #1f9a9a;
  --coral: #f46f5e;
  --yellow: #f7bd3b;
  --paper: #fffaf0;
  --white: #fffdf8;
  --leaf: #6fa56f;
  --shadow: 0 24px 80px rgba(23, 73, 107, 0.18);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--paper);
}

a {
  color: inherit;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(20px, 5vw, 72px);
  background: rgba(255, 250, 240, 0.92);
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(23, 73, 107, 0.1);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-weight: 800;
}

.brand img {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  object-fit: cover;
}

nav {
  display: flex;
  gap: clamp(14px, 3vw, 30px);
  font-size: 15px;
  font-weight: 700;
}

nav a {
  text-decoration: none;
}

.hero {
  min-height: calc(100vh - 79px);
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(340px, 1.08fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: center;
  padding: clamp(34px, 6vw, 84px) clamp(20px, 5vw, 72px) clamp(42px, 7vw, 96px);
}

.hero-copy {
  max-width: 680px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--teal);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 22px;
  font-size: clamp(48px, 8vw, 88px);
  line-height: 0.95;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(34px, 5vw, 58px);
  line-height: 1;
  letter-spacing: 0;
}

.lead,
.book-section p,
.starter-section p {
  font-size: clamp(19px, 2vw, 24px);
  line-height: 1.45;
}

.actions,
.social-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button,
.social-links a {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  padding: 13px 18px;
  text-decoration: none;
  font-weight: 800;
}

.primary {
  color: var(--white);
  background: var(--coral);
}

.secondary,
.social-links a {
  color: var(--ink);
  background: var(--white);
  border: 2px solid rgba(23, 73, 107, 0.14);
}

.hero-art {
  margin: 0;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: var(--shadow);
  background: var(--white);
}

.hero-art img {
  display: block;
  width: 100%;
  height: min(66vh, 680px);
  object-fit: cover;
}

.book-section,
.kakuro-section,
.collections-section,
.starter-section,
.follow-section {
  padding: clamp(48px, 8vw, 96px) clamp(20px, 5vw, 72px);
}

.kakuro-section {
  display: grid;
  grid-template-columns: minmax(0, 0.94fr) minmax(320px, 1.06fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: center;
  background: var(--ink);
  color: var(--white);
}

.kakuro-section .eyebrow {
  color: var(--yellow);
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.steps article {
  min-height: 190px;
  padding: 24px;
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.1);
  border: 1px solid rgba(255, 253, 248, 0.18);
}

.steps span {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  border-radius: 50%;
  background: var(--yellow);
  color: var(--ink);
  font-weight: 900;
}

.steps p {
  margin: 0;
  font-size: 18px;
  line-height: 1.45;
}

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

.collection-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 32px;
}

.collection-grid article {
  min-height: 210px;
  padding: 24px;
  border-radius: 8px;
  background: var(--paper);
  border: 1px solid rgba(23, 73, 107, 0.12);
}

.collection-grid span {
  display: block;
  margin-bottom: 16px;
  color: var(--teal);
  font-size: 20px;
  font-weight: 900;
}

.collection-grid p {
  margin: 0;
  font-size: 18px;
  line-height: 1.45;
}

.book-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.82fr);
  gap: clamp(30px, 6vw, 84px);
  align-items: center;
  background: var(--white);
}

.facts {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.facts div {
  min-height: 142px;
  padding: 24px;
  border-radius: 8px;
  background: var(--paper);
  border: 1px solid rgba(23, 73, 107, 0.12);
}

.facts dt {
  font-size: clamp(31px, 4vw, 50px);
  font-weight: 900;
  line-height: 1;
}

.facts dd {
  margin: 10px 0 0;
  font-weight: 800;
  color: var(--teal);
}

.starter-section {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
  background:
    linear-gradient(90deg, rgba(247, 189, 59, 0.24), rgba(31, 154, 154, 0.18)),
    var(--paper);
}

.starter-list {
  display: grid;
  gap: 10px;
  margin: 24px 0 0;
  padding-left: 20px;
  font-size: 18px;
  line-height: 1.4;
  font-weight: 700;
}

.signup-card {
  width: min(100%, 390px);
  padding: 28px;
  border-radius: 8px;
  background: var(--white);
  box-shadow: var(--shadow);
  border: 1px solid rgba(23, 73, 107, 0.12);
}

.signup-card h3 {
  margin: 0 0 12px;
  font-size: 28px;
  line-height: 1.05;
}

.signup-card p {
  margin-bottom: 22px;
  font-size: 17px;
  line-height: 1.45;
}

.signup-card small {
  display: block;
  margin-top: 14px;
  color: rgba(23, 73, 107, 0.72);
  font-weight: 700;
}

.section-copy {
  max-width: 790px;
}

.follow-section {
  background: var(--ink);
  color: var(--white);
  text-align: center;
}

.follow-section h2 {
  margin-bottom: 18px;
}

.follow-section .social-links {
  justify-content: center;
}

.follow-section .social-links a {
  background: rgba(255, 253, 248, 0.1);
  color: var(--white);
  border-color: rgba(255, 253, 248, 0.18);
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 28px clamp(20px, 5vw, 72px);
  background: #123a56;
  color: var(--white);
  font-weight: 700;
}

footer p {
  margin: 0;
}

@media (max-width: 860px) {
  .site-header,
  footer,
  .starter-section {
    align-items: flex-start;
    flex-direction: column;
  }

  .hero,
  .kakuro-section,
  .book-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  .hero-art {
    order: -1;
  }

  .hero-art img {
    height: 48vh;
    min-height: 340px;
  }

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

  .collection-grid,
  .steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  nav {
    width: 100%;
    justify-content: space-between;
  }

  h1 {
    font-size: 44px;
  }

  .button,
  .social-links a {
    width: 100%;
  }

  .collection-grid,
  .steps {
    grid-template-columns: 1fr;
  }
}