:root {
  --bg: #050b14;
  --bg-soft: #0c1a2a;
  --card-bg: #101f33;
  --accent: #236095;       /* cap blue */
  --accent-soft: #2f7ec0;
  --accent-strong: #4ea1ff;
  --text-main: #f9fafb;
  --text-muted: #9ca3af;
  --border-subtle: rgba(148, 163, 184, 0.35);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Calibri", "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: radial-gradient(circle at top, #0f172a, #020617 60%);
  color: var(--text-main);
}

a {
  color: inherit;
  text-decoration: none;
}

/* HEADER */

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(6, 12, 24, 0.96);
  backdrop-filter: blur(14px);
  position: sticky;
  top: 0;
  z-index: 20;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 999px;
  background: linear-gradient(145deg, var(--accent), var(--accent-soft));
  font-weight: 700;
  letter-spacing: 0.05em;
  font-size: 0.85rem;
}

.logo-text {
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-size: 0.8rem;
}

.nav a {
  margin-left: 16px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.nav a.active,
.nav a:hover {
  color: var(--text-main);
}

/* LAYOUT */

main {
  max-width: 1120px;
  margin: 0 auto;
  padding: 26px 16px 60px;
}

/* HERO */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  gap: 26px;
  align-items: center;
  margin-bottom: 18px;
}

.eyebrow {
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-strong);
  margin: 0 0 6px;
}

.hero-text h1 {
  font-size: clamp(1.9rem, 3vw, 2.4rem);
  margin: 0 0 10px;
}

.hero-summary {
  margin: 0 0 10px;
  color: var(--text-muted);
  font-size: 0.96rem;
}

.hero-benefits {
  margin: 0 0 14px;
  padding-left: 18px;
  color: var(--text-muted);
  font-size: 0.92rem;
}

.hero-benefits li + li {
  margin-top: 4px;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* HERO IMAGES */

.hero-images {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: center;
}

.hero-main-image {
  width: 100%;
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background: #020617;
}

.hero-main-image img {
  display: block;
  width: 100%;
  height: auto;
}

.hero-book-card {
  display: flex;
  align-items: center;
  gap: 10px;
  border-radius: 14px;
  padding: 8px 10px;
  background: radial-gradient(circle at top, #0b1726, #020817);
  border: 1px solid var(--border-subtle);
}

.hero-book-card img {
  display: block;
  width: 72px;
  height: auto;
  border-radius: 4px;
}

.hero-book-meta {
  font-size: 0.82rem;
}

.hero-book-title {
  margin: 0 0 2px;
  font-weight: 600;
}

.hero-book-authors {
  margin: 0;
  color: var(--text-muted);
}

/* BUTTONS */

.button {
  padding: 9px 16px;
  border-radius: 999px;
  font-size: 0.9rem;
  border: 1px solid transparent;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  white-space: nowrap;
}

.button.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-soft));
  color: white;
}

.button.secondary {
  border-color: var(--border-subtle);
  background: rgba(8, 18, 32, 0.9);
  color: var(--text-main);
}

.button.ghost {
  border-color: rgba(148, 163, 184, 0.5);
  background: transparent;
  color: var(--text-main);
}

.button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(15, 23, 42, 0.7);
}

/* VALUE STRIP */

.value-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 22px;
}

.value-item {
  padding: 16px 18px;
  border-radius: 16px;
  background: radial-gradient(circle at top left, #111827, #020617);
  border: 1px solid rgba(148, 163, 184, 0.3);
}

.value-item h3 {
  margin: 0 0 6px;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.value-item p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* SECTIONS */

.section {
  margin-top: 22px;
  padding: 20px 22px;
  border-radius: 18px;
  background: radial-gradient(circle at top left, #111827, #020617);
  border: 1px solid rgba(148, 163, 184, 0.3);
}

.section h2 {
  margin-top: 0;
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.95rem;
}

.section h3 {
  margin-top: 0;
  margin-bottom: 6px;
  font-size: 1rem;
}

.section p,
.section ul {
  color: var(--text-muted);
  font-size: 0.93rem;
  line-height: 1.5;
}

.section ul {
  padding-left: 18px;
}

/* TWO COLUMN */

.two-column {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: 18px;
}

.authors > div + div {
  border-left: 1px solid rgba(148, 163, 184, 0.25);
  padding-left: 18px;
}

/* FULL DESCRIPTION TOGGLE */

.full-description {
  margin-top: 8px;
}

.full-description.collapsed {
  display: none;
}

.link-button {
  margin-top: 10px;
  padding: 6px 0;
  border: none;
  background: none;
  color: var(--accent-strong);
  font-size: 0.9rem;
  cursor: pointer;
  text-decoration: underline;
}

/* FINAL CTA */

.final-cta {
  margin-top: 22px;
}

.final-cta-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.final-cta-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* CHAT PAGE ELEMENTS (ai.html) */

.chat-container {
  margin-top: 14px;
}

.chat-window {
  max-height: 340px;
  overflow-y: auto;
  padding: 12px 14px;
  border-radius: 14px;
  background: linear-gradient(145deg, #050b14, #071121);
  border: 1px solid var(--border-subtle);
}

.chat-message {
  margin-bottom: 10px;
  padding: 10px 12px;
  border-radius: 12px;
  font-size: 0.95rem;
}

.chat-message.system {
  background: rgba(15, 23, 42, 0.9);
}

.chat-label {
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent-strong);
  margin-bottom: 4px;
}

.chat-input {
  display: flex;
  gap: 8px;
  margin-top: 10px;
}

.chat-input input {
  flex: 1 1 auto;
  padding: 9px 10px;
  border-radius: 999px;
  border: 1px solid var(--border-subtle);
  background: rgba(15, 23, 42, 0.9);
  color: var(--text-main);
  font-size: 0.9rem;
}

.chat-input button {
  padding: 9px 14px;
  border-radius: 999px;
  border: 1px solid var(--border-subtle);
  background: rgba(15, 23, 42, 0.9);
  color: var(--text-muted);
  font-size: 0.9rem;
  cursor: not-allowed;
}

.coming-soon-note {
  margin-top: 8px;
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* FOOTER */

.site-footer {
  text-align: center;
  padding: 14px 16px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.8rem;
  color: var(--text-muted);
  background: #020617;
}

/* RESPONSIVE */

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
  }
  .value-strip {
    grid-template-columns: 1fr;
  }
  .two-column {
    grid-template-columns: 1fr;
  }
  .authors > div + div {
    border-left: none;
    padding-left: 0;
  }
}

@media (max-width: 720px) {
  .site-header {
    flex-direction: column;
    align-items: flex-start;
  }
  .nav {
    margin-top: 6px;
  }
}