:root {
  --ink: #21180f;
  --muted: #6d5d4f;
  --paper: #fffaf0;
  --cream: #f8edd8;
  --gold: #d89a2b;
  --gold-dark: #a86912;
  --green: #1f6b55;
  --green-dark: #164d3e;
  --white: #ffffff;
  --line: rgba(77, 50, 24, 0.16);
  --shadow: 0 24px 70px rgba(55, 35, 12, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(216, 154, 43, 0.24), transparent 32rem),
    linear-gradient(180deg, #fff8ec 0%, #fbf1df 45%, #f7ead5 100%);
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(33, 24, 15, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(33, 24, 15, 0.035) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: linear-gradient(to bottom, #000, transparent 75%);
}

a {
  color: inherit;
}

button,
input,
select {
  font: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1rem clamp(1rem, 3vw, 3rem);
  background: rgba(255, 250, 240, 0.88);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 16px;
  background: linear-gradient(135deg, var(--green), var(--gold));
  color: var(--white);
  font-weight: 800;
  box-shadow: 0 12px 30px rgba(31, 107, 85, 0.25);
}

.brand small {
  display: block;
  color: var(--muted);
  margin-top: 0.12rem;
}

nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-weight: 700;
  color: #4f3f30;
}

nav a {
  text-decoration: none;
}

.nav-button {
  padding: 0.72rem 1rem;
  border-radius: 999px;
  background: var(--ink);
  color: var(--white);
}

.section-pad {
  padding: clamp(3rem, 6vw, 6rem) clamp(1rem, 5vw, 5rem);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
  align-items: center;
  gap: clamp(2rem, 5vw, 5rem);
  min-height: 720px;
}

.eyebrow {
  margin: 0 0 0.9rem;
  color: var(--gold-dark);
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.78rem;
}

h1,
h2,
h3 {
  font-family: 'Crimson Text', Georgia, serif;
  line-height: 0.96;
  margin: 0;
}

h1 {
  font-size: clamp(3.4rem, 8vw, 7.8rem);
  max-width: 980px;
}

h2 {
  font-size: clamp(2.3rem, 5vw, 4.4rem);
}

h3 {
  font-size: 1.75rem;
}

.hero-text,
.author-section p,
.contact-section p,
.assistant-intro p {
  color: var(--muted);
  font-size: 1.08rem;
  line-height: 1.8;
}

.hero-text {
  max-width: 720px;
}

.hero-actions,
.hero-stats,
.filters,
.prompt-chips,
.contact-section {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.85rem 1.15rem;
  border: 0;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 800;
  cursor: pointer;
}

.button.primary {
  color: var(--white);
  background: linear-gradient(135deg, var(--green), var(--green-dark));
  box-shadow: 0 14px 32px rgba(31, 107, 85, 0.25);
}

.button.ghost {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.64);
  border: 1px solid var(--line);
}

.hero-stats {
  margin-top: 2rem;
}

.hero-stats span {
  padding: 1rem 1.2rem;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.54);
  color: var(--muted);
}

.hero-stats strong {
  color: var(--ink);
  font-size: 1.25rem;
}

.hero-card {
  border: 1px solid var(--line);
  border-radius: 32px;
  padding: clamp(1.5rem, 4vw, 3rem);
  background: rgba(255, 255, 255, 0.58);
  box-shadow: var(--shadow);
}

.book-stack {
  position: relative;
  min-height: 340px;
  display: grid;
  place-items: center;
}

.stack-book {
  position: absolute;
  width: 210px;
  height: 300px;
  display: grid;
  place-items: center;
  padding: 1rem;
  border-radius: 18px 10px 10px 18px;
  color: var(--white);
  font-family: 'Crimson Text', Georgia, serif;
  font-size: 2rem;
  text-align: center;
  box-shadow: 0 28px 48px rgba(54, 33, 12, 0.24);
}

.stack-book.one {
  transform: rotate(-12deg) translateX(-52px);
  background: linear-gradient(145deg, #8b3f22, #d89a2b);
}

.stack-book.two {
  transform: rotate(4deg) translateY(-12px);
  background: linear-gradient(145deg, #163e62, #1f6b55);
}

.stack-book.three {
  transform: rotate(13deg) translateX(56px) translateY(18px);
  background: linear-gradient(145deg, #2d2149, #9868c9);
}

.hero-note {
  padding: 1.4rem;
  border-radius: 22px;
  background: var(--paper);
  border: 1px solid var(--line);
}

.hero-note p {
  color: var(--muted);
  line-height: 1.7;
}

.store-toolbar {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 2rem;
  padding-bottom: 1rem;
}

.filters input,
.filters select,
.chat-form input {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0 1rem;
  background: rgba(255, 255, 255, 0.78);
  color: var(--ink);
  outline: none;
}

.filters input {
  width: min(72vw, 320px);
}

.book-grid {
  padding-top: 1.5rem;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}

.book-card {
  display: flex;
  flex-direction: column;
  min-height: 100%;
  border: 1px solid var(--line);
  border-radius: 28px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.7);
  box-shadow: 0 18px 42px rgba(55, 35, 12, 0.08);
}

.cover {
  min-height: 250px;
  display: grid;
  place-items: center;
  padding: 1.5rem;
  background: linear-gradient(135deg, rgba(31, 107, 85, 0.92), rgba(216, 154, 43, 0.9));
  color: var(--white);
  text-align: center;
}

.cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 18px;
}

.cover-title {
  font-family: 'Crimson Text', Georgia, serif;
  font-size: 2.1rem;
  line-height: 0.95;
}

.book-body {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  flex: 1;
}

.meta-row,
.book-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem;
}

.badge {
  display: inline-flex;
  padding: 0.42rem 0.65rem;
  border-radius: 999px;
  background: var(--cream);
  color: #644b2f;
  font-size: 0.82rem;
  font-weight: 800;
}

.book-description {
  color: var(--muted);
  line-height: 1.7;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: auto;
}

.tag {
  font-size: 0.76rem;
  color: var(--green-dark);
  background: rgba(31, 107, 85, 0.1);
  border-radius: 999px;
  padding: 0.32rem 0.5rem;
  font-weight: 700;
}

.assistant-section {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(320px, 1.15fr);
  gap: 2rem;
}

code {
  background: rgba(33, 24, 15, 0.08);
  padding: 0.1rem 0.3rem;
  border-radius: 6px;
}

.prompt-chips button {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.7rem 0.9rem;
  background: rgba(255, 255, 255, 0.65);
  color: var(--ink);
  cursor: pointer;
  font-weight: 700;
}

.chat-card {
  border: 1px solid var(--line);
  border-radius: 28px;
  background: rgba(255, 255, 255, 0.72);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.chat-log {
  height: 470px;
  overflow-y: auto;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.message {
  width: min(90%, 680px);
  border-radius: 22px;
  padding: 0.9rem 1rem;
  line-height: 1.6;
}

.message p {
  margin: 0.35rem 0 0;
}

.assistant-message {
  align-self: flex-start;
  background: var(--cream);
}

.user-message {
  align-self: flex-end;
  color: var(--white);
  background: var(--green);
}

.chat-form {
  display: flex;
  gap: 0.65rem;
  padding: 1rem;
  border-top: 1px solid var(--line);
  background: rgba(255, 250, 240, 0.85);
}

.chat-form input {
  flex: 1;
  border-radius: 16px;
}

.author-section,
.contact-section {
  border-top: 1px solid var(--line);
}

.author-section {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.1fr);
  gap: 2rem;
  align-items: start;
}

.contact-section {
  justify-content: space-between;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 2rem clamp(1rem, 5vw, 5rem);
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 980px) {
  .site-header,
  .store-toolbar,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 0.2rem;
  }

  .hero,
  .assistant-section,
  .author-section {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 680px) {
  h1 {
    font-size: clamp(3rem, 18vw, 4.2rem);
  }

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

  .chat-form {
    flex-direction: column;
  }

  .stack-book {
    width: 170px;
    height: 250px;
  }
}