/* ============================================================
   CSS Custom Properties
   ============================================================ */
:root {
  --font-heading: 'Libre Baskerville', Georgia, serif;
  --font-body: 'Lato', system-ui, -apple-system, sans-serif;

  --color-bg:       #FAFAF8;
  --color-bg-alt:   #F3F0EB;
  --color-text:     #1C1C1C;
  --color-muted:    #5A5A5A;
  --color-accent:   #7A1C1C;
  --color-accent-d: #5E1515;
  --color-border:   #DDD9D3;

  --max-width:        1100px;
  --max-width-narrow: 720px;

  --header-height: 80px;
}

/* ============================================================
   Reset & Base
   ============================================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  color: var(--color-text);
  background-color: var(--color-bg);
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* Offset anchor targets so the sticky header doesn't hide them */
[id] {
  scroll-margin-top: calc(var(--header-height) + 1rem);
}

/* ============================================================
   Layout Utilities
   ============================================================ */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: 1.25rem;
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

/* ============================================================
   Header & Navigation
   ============================================================ */
.site-header {
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  padding-bottom: 100px;
  padding-top: 40px;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  height: 100%;
  padding-bottom: 20px;
}

.logo-link {
  display: block;
  flex-shrink: 0;
  line-height: 0;
}

.logo {
  height: 52px;
  width: auto;
}

.site-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0 1.2rem;
}

.site-nav a {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text);
  text-decoration: none;
  padding-block: 0.25rem;
  border-bottom: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}

.site-nav a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
  text-decoration: none;
}

/* ============================================================
   Intro Section
   ============================================================ */
.intro-section {
  padding-block: 4rem;
  border-bottom: 1px solid var(--color-border);
}

.intro-text {
  font-family: var(--font-heading);
  font-style: italic;
  font-size: 1rem;
  line-height: 1.9;
  text-align: center;
  color: var(--color-muted);
}

.intro-text a {
  color: var(--color-accent);
}

/* ============================================================
   Section Headings
   ============================================================ */
.section-heading {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  margin-bottom: 2.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-border);
}

/* ============================================================
   Books Section
   ============================================================ */
.books-section {
  padding-block: 4rem;
}

/* Single-column by default (mobile) */
.book-card {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-bottom: 4rem;
  padding-bottom: 4rem;
  border-bottom: 1px solid var(--color-border);
}

.book-card:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.book-card__cover {
  width: 100%;
  max-width: 240px;
  margin-inline: auto;
}

.book-card__cover img {
  border-radius: 2px;
  box-shadow: 0 6px 28px rgba(0, 0, 0, 0.2);
}

.book-card__title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 0.4rem;
}

.book-card__author {
  font-family: var(--font-heading);
  font-style: italic;
  font-size: 1rem;
  color: var(--color-muted);
  margin-bottom: 1.25rem;
}

.book-card__description {
  line-height: 1.8;
  color: var(--color-text);
  max-width: 58ch;
  margin-bottom: 1.75rem;
}

/* ============================================================
   Buy Buttons
   ============================================================ */
.buy-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.btn {
  display: inline-block;
  padding: 0.6rem 1.4rem;
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: 2px;
  border: 2px solid var(--color-accent);
  transition: background-color 0.15s, color 0.15s;
  cursor: pointer;
}

.btn--primary {
  background-color: var(--color-accent);
  color: #fff;
}

.btn--primary:hover {
  background-color: var(--color-accent-d);
  border-color: var(--color-accent-d);
  color: #fff;
  text-decoration: none;
}

.btn--secondary {
  background-color: transparent;
  color: var(--color-accent);
}

.btn--secondary:hover {
  background-color: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

/* ============================================================
   Content Sections (About / Services / Contact)
   ============================================================ */
.content-section {
  padding-block: 3.5rem;
  border-top: 1px solid var(--color-border);
}

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

.content-section p {
  line-height: 1.8;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  background-color: var(--color-text);
  color: #aaa;
  text-align: center;
  padding-block: 1.5rem;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
}

.site-footer a {
  color: #aaa;
}

/* ============================================================
   Buy Page — Hero
   ============================================================ */
.buy-hero {
  padding-block: 3.5rem;
  border-bottom: 1px solid var(--color-border);
}

.buy-hero__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  align-items: center;
}

.buy-hero__cover {
  max-width: 200px;
  margin-inline: auto;
}

.buy-hero__cover img {
  border-radius: 2px;
  box-shadow: 0 6px 28px rgba(0, 0, 0, 0.2);
}

.buy-hero__label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.5rem;
}

.buy-hero__title {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 0.4rem;
}

.buy-hero__author {
  font-family: var(--font-heading);
  font-style: italic;
  color: var(--color-muted);
  margin-bottom: 1rem;
}

.buy-hero__tagline {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-muted);
  max-width: 48ch;
}

/* ============================================================
   Buy Page — Options
   ============================================================ */
.buy-options-section {
  padding-block: 3.5rem;
}

.buy-options {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.buy-option {
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 1.75rem;
  background-color: var(--color-bg);
}

.buy-option__header {
  margin-bottom: 1rem;
}

.buy-option__badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  background-color: var(--color-accent);
  color: #fff;
  padding: 0.25rem 0.65rem;
  border-radius: 2px;
}

.buy-option__badge--alt {
  background-color: #1a1a1a;
}

.buy-option__desc {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--color-muted);
  margin-bottom: 1.25rem;
}

.buy-option__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ============================================================
   Desktop layout (≥ 700px)
   ============================================================ */
@media (min-width: 700px) {
  .logo {
    height: 60px;
  }

  /* Side-by-side: cover left, info right */
  .book-card {
    grid-template-columns: 220px 1fr;
    align-items: start;
  }

  .book-card__cover {
    margin-inline: 0;
  }
}

@media (min-width: 900px) {
  .book-card {
    grid-template-columns: 260px 1fr;
    gap: 3rem;
  }

  .buy-hero__inner {
    grid-template-columns: 180px 1fr;
  }

  .buy-hero__cover {
    margin-inline: 0;
  }

  .buy-options {
    grid-template-columns: 1fr 1fr;
  }
}