:root {
  --primary: #2b8d95;
  --secondary: #133853;
  --on-primary: #111111;
  --on-secondary: #ffffff;
  --bg: #ffffff;
  --surface: #f5f7fa;
  --light: #eef1f6;
  --dark: #1a1a1a;
  --muted: #5b6472;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol';
  color: var(--dark);
  background-color: var(--bg);
  line-height: 1.6;
}

.header {
  background-color: var(--bg);
  border-bottom: 1px solid var(--light);
}

.logo {
  max-height: 60px;
  width: auto;
}

.hero {
  background-color: var(--surface);
  padding-top: 70px;
  padding-bottom: 70px;
}

.hero h1 {
  color: var(--dark);
  font-size: 3.5rem;
}

.hero .lead {
  color: var(--muted);
  font-size: 1.25rem;
}

.book-cover {
  max-width: 350px;
  border-radius: 12px;
}

.lead-form-card {
  background-color: var(--bg);
  border-radius: 12px;
  box-shadow: 0 6px 16px rgba(0,0,0,0.1);
  max-width: 450px;
}

.lead-form-card .form-control {
  border: 1px solid var(--light);
  padding: 12px 15px;
  border-radius: 8px;
  color: var(--dark);
  background-color: var(--bg);
}

.lead-form-card .form-control::placeholder {
  color: var(--muted);
}

.lead-form-card .form-control:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 0.25rem rgba(43, 141, 149, 0.25);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: auto;
  max-width: 100%;
  padding: 14px 28px;
  margin: 8px 0;
  gap: 8px;
  border: none;
  border-radius: 10px;
  font-weight: 600;
  font-size: 16px;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  box-sizing: border-box;
  cursor: pointer;
  transition: filter 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
  min-height: 44px;
}

.btn-cta {
  background: var(--primary);
  color: var(--on-primary) !important;
  box-shadow: 0 6px 16px rgba(0,0,0,0.15);
}

.btn-secondary {
  background: var(--secondary);
  color: var(--on-secondary) !important;
}

.btn-cta:hover, .btn-secondary:hover {
  filter: brightness(0.92);
  box-shadow: 0 8px 20px rgba(0,0,0,0.20);
  transform: translateY(-1px);
}

section {
  padding-top: 70px;
  padding-bottom: 70px;
}

section.bg-surface {
  background-color: var(--surface);
}

h2, h3, h4 {
  color: var(--dark);
}

.card {
  border: none;
  border-radius: 12px;
  background-color: var(--bg);
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0,0,0,0.1);
}

.chapter-item.card {
  background-color: var(--bg);
}

.footer {
  background-color: var(--secondary);
  color: var(--on-secondary);
  padding: 40px 0;
}

.footer p {
  margin-bottom: 0;
}

@media (max-width: 991.98px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  .hero .lead {
    font-size: 1.1rem;
  }
  .book-cover {
    max-width: 280px;
  }
}

@media (max-width: 767.98px) {
  .hero .text-md-start {
    text-align: center !important;
  }
  .hero .mx-md-0 {
    margin-left: auto !important;
    margin-right: auto !important;
  }
  .btn {
    width: 100%;
    margin-left: 0;
    margin-right: 0;
  }
  .hero,
  .what-you-get,
  .whats-inside,
  .about-author,
  .final-cta {
    padding-top: 40px;
    padding-bottom: 40px;
  }
}