/**
 * 1. CSS Reset / Normalize
 */

*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img,
picture,
svg,
video {
  display: block;
  max-width: 100%;
}

img {
  height: auto;
}

input,
button,
textarea,
select {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
}

ul[role="list"],
ol[role="list"] {
  list-style: none;
  padding: 0;
}

/**
 * 2. Design tokens (custom properties)
 */

:root {
  /* Colors: ink (deep navy), paper (warm cream), sage (cover green), gold */
  --color-ink: #1c2531;
  --color-ink-deep: #131a24;
  --color-ink-soft: #2b3646;
  --color-ink-muted: #5b6674;
  --color-paper: #f7f4ec;
  --color-paper-alt: #efeadd;
  --color-paper-dim: #fdfcf8;
  --color-line: #ddd5c2;
  --color-line-dark: #364154;
  --color-sage: #8fb6a1;
  --color-sage-tint: #e3ece6;
  --color-sage-deep: #3e6a54;
  --color-sage-dark: #31553f;
  --color-gold: #b9a75d;
  --color-gold-soft: #d8cd95;
  --color-focus-ring: #8a5a00;
  --color-error: #a33a2a;
  --color-success: #2f6b46;

  /* Text colors on light / dark surfaces */
  --color-text: var(--color-ink);
  --color-text-muted: var(--color-ink-muted);
  --color-text-on-dark: #ece7da;
  --color-text-on-dark-muted: #a8b0ba;

  /* Typography */
  --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  --font-family-heading: "Iowan Old Style", "Palatino Linotype", "Book Antiqua",
    Palatino, Georgia, "Times New Roman", serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-md: 1.125rem;
  --font-size-lg: 1.25rem;
  --font-size-xl: 1.5rem;
  --font-size-2xl: 2rem;
  --font-size-3xl: 2.5rem;
  --font-size-4xl: 3.25rem;
  --font-size-5xl: 4rem;
  --line-height-tight: 1.2;
  --line-height-base: 1.6;
  --line-height-relaxed: 1.8;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Borders */
  --border-radius: 0.25rem;
  --border-width: 0.0625rem;
  --border-color: var(--color-line);

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(19, 26, 36, 0.08);
  --shadow-md: 0 4px 6px rgba(19, 26, 36, 0.1);
  --shadow-lg: 0 12px 28px rgba(19, 26, 36, 0.16);
  --shadow-book: 10px 14px 0 var(--color-sage-tint), 0 24px 48px rgba(19, 26, 36, 0.35);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;

  /* Z-index scale */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-overlay: 300;
  --z-modal: 400;
  --z-toast: 500;

  /* Layout */
  --container-max-width: 75rem;
  --container-padding: var(--space-md);
  --header-height: 4.5rem;
}

/**
 * 3. Base / element styles
 */

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text);
  background-color: var(--color-paper);
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-family-heading);
  font-weight: var(--font-weight-semibold);
  line-height: var(--line-height-tight);
  color: var(--color-ink);
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

a {
  color: var(--color-sage-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--color-sage-dark);
}

:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

::selection {
  background-color: var(--color-sage);
  color: var(--color-ink-deep);
}

.skip-link {
  position: absolute;
  left: var(--space-sm);
  top: var(--space-sm);
  z-index: var(--z-toast);
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-paper);
  color: var(--color-ink);
  border: 2px solid var(--color-focus-ring);
  border-radius: var(--border-radius);
  font-weight: var(--font-weight-semibold);
  text-decoration: none;
  transform: translateY(-200%);
}

.skip-link:focus-visible {
  transform: translateY(0);
}

/**
 * 4. Layout (containers, grids, page structure)
 */

.container {
  max-width: var(--container-max-width);
  margin-inline: auto;
  padding-inline: var(--container-padding);
}

.section {
  padding-block: var(--space-4xl);
  scroll-margin-top: calc(var(--header-height) + 1rem);
}

.section--tight {
  padding-block: var(--space-2xl);
}

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

.section--white {
  background-color: var(--color-paper-dim);
}

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

.section--ink {
  background-color: var(--color-ink);
  color: var(--color-text-on-dark);
}

.section--ink h2,
.section--ink h3 {
  color: var(--color-paper);
}

.section-head {
  max-width: 46rem;
  margin-bottom: var(--space-2xl);
}

.section-head--center {
  margin-inline: auto;
  text-align: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-sage-deep);
  margin-bottom: var(--space-md);
}

.eyebrow::before {
  content: "";
  width: 2rem;
  height: 2px;
  background-color: var(--color-gold);
  flex: none;
}

.section--ink .eyebrow {
  color: var(--color-gold-soft);
}

.section-title {
  font-size: var(--font-size-3xl);
  margin-bottom: var(--space-md);
}

.section-lead {
  font-size: var(--font-size-md);
  color: var(--color-text-muted);
  max-width: 40rem;
}

.section--ink .section-lead {
  color: var(--color-text-on-dark-muted);
}

.section-head--center .section-lead {
  margin-inline: auto;
}

.grid {
  display: grid;
  gap: var(--space-lg);
}

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

.grid--three {
  grid-template-columns: repeat(3, 1fr);
}

.grid--four {
  grid-template-columns: repeat(4, 1fr);
}

/**
 * 5. Components
 */

/* ---------- Reading progress indicator ---------- */

.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  z-index: var(--z-toast);
  width: 100%;
  height: 3px;
  background-color: var(--color-gold);
  transform-origin: left;
  transform: scaleX(0);
  pointer-events: none;
}

/* ---------- Site header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background-color: var(--color-ink-deep);
  border-bottom: 1px solid var(--color-line-dark);
  transition: box-shadow var(--transition-base);
}

.site-header.is-scrolled {
  box-shadow: var(--shadow-lg);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-lg);
  min-height: var(--header-height);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-md);
  text-decoration: none;
  color: var(--color-paper);
}

.brand__logo {
  flex: none;
  width: 2.5rem;
  height: 2.5rem;
  object-fit: cover;
  border: 1px solid var(--color-gold-soft);
  border-radius: var(--border-radius);
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.brand__title {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
}

.brand__publisher {
  font-size: var(--font-size-xs);
  letter-spacing: 0.01em;
  color: var(--color-text-on-dark-muted);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.site-nav__link {
  display: inline-block;
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-on-dark);
  text-decoration: none;
  border-radius: var(--border-radius);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.site-nav__link:hover {
  color: var(--color-gold-soft);
  background-color: var(--color-ink-soft);
}

.site-nav__link.is-active {
  color: var(--color-gold-soft);
  box-shadow: inset 0 -2px 0 var(--color-gold);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.nav-toggle {
  display: none;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0.5rem;
  background-color: transparent;
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
  color: var(--color-paper);
}

.nav-toggle__bars {
  position: relative;
  width: 100%;
  height: 100%;
}

.nav-toggle__bars span,
.nav-toggle__bars span::before,
.nav-toggle__bars span::after {
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: currentColor;
  border-radius: 1px;
  content: "";
}

.nav-toggle__bars span {
  top: 50%;
  transform: translateY(-50%);
  transition: background-color var(--transition-fast);
}

.nav-toggle__bars span::before {
  top: -0.4rem;
}

.nav-toggle__bars span::after {
  top: 0.4rem;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span {
  background-color: transparent;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span::after {
  top: 0;
  transform: rotate(-45deg);
}

.nav-toggle__bars span::before,
.nav-toggle__bars span::after {
  transition: transform var(--transition-fast), top var(--transition-fast);
}

.mobile-nav {
  display: none;
}

/* ---------- Buttons ---------- */

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  min-height: 2.75rem;
  padding: var(--space-sm) var(--space-lg);
  border: 1px solid transparent;
  border-radius: var(--border-radius);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: background-color var(--transition-fast), color var(--transition-fast),
    border-color var(--transition-fast), transform var(--transition-fast),
    box-shadow var(--transition-fast);
}

.button:active {
  transform: translateY(1px);
}

.button--primary {
  background-color: var(--color-sage-deep);
  color: #ffffff;
}

.button--primary:hover {
  background-color: var(--color-sage-dark);
  color: #ffffff;
}

.button--gold {
  background-color: var(--color-gold);
  color: var(--color-ink-deep);
}

.button--gold:hover {
  background-color: var(--color-gold-soft);
  color: var(--color-ink-deep);
}

.button--ghost-light {
  border-color: var(--color-gold-soft);
  color: var(--color-gold-soft);
  background-color: transparent;
}

.button--ghost-light:hover {
  background-color: var(--color-gold-soft);
  color: var(--color-ink-deep);
}

.button--ghost {
  border-color: var(--color-sage-deep);
  color: var(--color-sage-deep);
  background-color: transparent;
}

.button--ghost:hover {
  background-color: var(--color-sage-deep);
  color: #ffffff;
}

.button--small {
  min-height: 2.25rem;
  padding: var(--space-xs) var(--space-md);
}

.button--icon {
  width: 2.75rem;
  min-height: 2.75rem;
  padding: 0.5rem;
}

.button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

/* ---------- Hero ---------- */

.hero {
  position: relative;
  background-color: var(--color-ink);
  color: var(--color-text-on-dark);
  overflow: hidden;
}

.hero__wave {
  position: absolute;
  inset: auto 0 -1px;
  width: 100%;
  height: 5rem;
  color: var(--color-paper);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  align-items: center;
  gap: var(--space-3xl);
  padding-block: var(--space-4xl);
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-gold-soft);
  margin-bottom: var(--space-lg);
}

.hero__eyebrow::before {
  content: "";
  width: 2.5rem;
  height: 2px;
  background-color: var(--color-gold);
}

.hero__title {
  font-size: var(--font-size-5xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-paper);
  margin-bottom: var(--space-sm);
}

.hero__subtitle {
  font-family: var(--font-family-heading);
  font-style: italic;
  font-size: var(--font-size-xl);
  color: var(--color-sage);
  margin-bottom: var(--space-md);
}

.hero__author {
  display: inline-flex;
  align-items: baseline;
  gap: var(--space-sm);
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
  color: var(--color-paper);
  margin-bottom: var(--space-lg);
}

.hero__author small {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-regular);
  color: var(--color-text-on-dark-muted);
}

.hero__hook {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-lg);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-on-dark);
  border-left: 2px solid var(--color-gold);
  padding-left: var(--space-lg);
  margin-bottom: var(--space-xl);
  max-width: 34rem;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-on-dark-muted);
}

.hero__meta li {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
}

.hero__meta li + li {
  margin-left: var(--space-sm);
}

.hero__meta svg {
  color: var(--color-gold-soft);
}

/* ---------- Book visual (cover) ---------- */

.book-stage {
  position: relative;
  display: grid;
  place-items: center;
  padding: var(--space-xl) 0;
}

.book-stage__trace {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  color: var(--color-gold);
  opacity: 0.45;
  pointer-events: none;
}

.book-stage__trace path {
  stroke-dasharray: 2200;
  stroke-dashoffset: 2200;
  animation: trace-draw 3.2s var(--transition-slow) forwards;
}

@keyframes trace-draw {
  to {
    stroke-dashoffset: 0;
  }
}

.book-visual {
  position: relative;
  width: min(20rem, 78%);
  transform-style: preserve-3d;
  transition: transform var(--transition-base);
}

.book-visual__frame {
  background-color: var(--color-paper);
  padding: var(--space-md);
  border: 1px solid var(--color-gold);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-book);
}

.book-visual__cover {
  width: 100%;
  border-radius: 2px;
  box-shadow: var(--shadow-md);
}

.book-visual__badge {
  position: absolute;
  bottom: calc(var(--space-lg) * -1);
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--color-paper);
  color: var(--color-ink);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: var(--space-xs) var(--space-md);
  border: 1px solid var(--color-gold);
  border-radius: var(--border-radius);
  white-space: nowrap;
  box-shadow: var(--shadow-sm);
}

/* ---------- Fact strip ---------- */

.fact-strip {
  background-color: var(--color-ink-deep);
  border-top: 1px solid var(--color-line-dark);
  color: var(--color-text-on-dark);
}

.fact-strip__inner {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  padding-block: var(--space-xl);
}

.fact {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.fact svg {
  flex: none;
  color: var(--color-gold-soft);
  width: 2rem;
  height: 2rem;
}

.fact__label {
  display: block;
  font-size: var(--font-size-xs);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-on-dark-muted);
  margin-bottom: var(--space-xs);
}

.fact__value {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
  color: var(--color-paper);
}

/* ---------- Wave divider ---------- */

.wave-divider {
  display: block;
  width: 100%;
  height: 2.5rem;
  color: var(--color-line);
}

/* ---------- Book page prose (back cover text) ---------- */

.book-grid {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: var(--space-3xl);
  align-items: start;
}

#kitap .book-grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
}

.book-page {
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  padding: var(--space-2xl) var(--space-2xl);
  position: relative;
}

.book-page__label {
  font-size: var(--font-size-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-gold);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-lg);
}

.book-page p {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-md);
  line-height: var(--line-height-relaxed);
  color: var(--color-ink);
  margin-bottom: var(--space-lg);
}

.book-page p:last-of-type {
  margin-bottom: 0;
}

.book-page p.lead-paragraph::first-letter {
  initial-letter: 3;
  -webkit-initial-letter: 3;
  font-size: 3.4em;
  float: left;
  line-height: 0.85;
  padding-right: var(--space-sm);
  color: var(--color-sage-deep);
  font-weight: var(--font-weight-semibold);
}

.book-page__final {
  border-top: 1px solid var(--color-line);
  padding-top: var(--space-lg);
  font-style: italic;
  color: var(--color-sage-dark) !important;
}

.book-page__credit {
  display: block;
  margin-top: var(--space-lg);
  font-family: var(--font-family-base);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  font-style: normal;
}

.book-page__credit strong {
  color: var(--color-ink);
}

.backcover-side {
  display: grid;
  gap: var(--space-lg);
  align-content: start;
}

.backcover-figure {
  position: sticky;
  top: calc(var(--header-height) + 1.5rem);
  text-align: center;
}

.backcover-figure__image {
  width: min(25rem, 92%);
  margin-inline: auto;
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
}

.backcover-figure figcaption {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-md);
}

/* Reason card: fills the shorter right column of the back-cover grid */
.reason-card {
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-left: 3px solid var(--color-sage-deep);
  border-radius: var(--border-radius);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
  text-align: left;
}

.reason-card__title {
  font-size: var(--font-size-md);
  margin-bottom: var(--space-md);
}

.reason-card__list {
  list-style: none;
  padding: 0;
  margin: 0;
  counter-reset: reason;
  display: grid;
  gap: var(--space-md);
}

.reason-card__item {
  position: relative;
  padding-left: 2.25rem;
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-muted);
  counter-increment: reason;
}

.reason-card__item::before {
  content: counter(reason, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.125rem;
  font-family: var(--font-family-heading);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  color: var(--color-gold);
}

/* ---------- Theme journey cards ---------- */

.theme-grid {
  counter-reset: theme;
}

.theme-card {
  position: relative;
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-top: 3px solid var(--color-sage-deep);
  border-radius: var(--border-radius);
  padding: var(--space-xl) var(--space-lg);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.theme-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.theme-card__icon {
  display: grid;
  place-items: center;
  width: 2.75rem;
  height: 2.75rem;
  background-color: var(--color-sage-tint);
  color: var(--color-sage-deep);
  border-radius: var(--border-radius);
  margin-bottom: var(--space-md);
}

.theme-card__route {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-xs);
  font-family: var(--font-family-heading);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-ink);
  margin-bottom: var(--space-sm);
}

.theme-card__route svg {
  color: var(--color-gold);
}

.theme-card__description {
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-muted);
}

/* ---------- Note deck widget ---------- */

.note-deck {
  background-color: var(--color-ink);
  border-radius: var(--border-radius);
  color: var(--color-text-on-dark);
  padding: var(--space-2xl) var(--space-xl);
  position: relative;
  overflow: hidden;
  max-width: 46rem;
  margin-inline: auto;
}

.note-deck::before {
  content: "";
  position: absolute;
  inset: var(--space-sm);
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
  pointer-events: none;
}

.note-deck__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.note-deck__title {
  font-size: var(--font-size-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-gold-soft);
  font-weight: var(--font-weight-semibold);
}

.note-deck__counter {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-sm);
  color: var(--color-text-on-dark-muted);
  white-space: nowrap;
}

.note-card {
  min-height: 9rem;
  display: flex;
  align-items: center;
}

.note-card__text {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-2xl);
  line-height: var(--line-height-base);
  color: var(--color-paper);
  transition: opacity var(--transition-base), transform var(--transition-base);
}

.note-card__text.is-leaving {
  opacity: 0;
  transform: translateY(0.75rem);
}

.note-deck__controls {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-xl);
}

/* ---------- Specs table ---------- */

.specs {
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  overflow: hidden;
}

.specs__row {
  display: grid;
  grid-template-columns: minmax(10rem, 1fr) 2fr;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--color-line);
}

.specs__row:last-child {
  border-bottom: 0;
}

.specs__term {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  color: var(--color-sage-dark);
  letter-spacing: 0.04em;
}

.specs__value {
  font-size: var(--font-size-xs);
  color: var(--color-ink);
}

/* Audience block next to the specs table */
.audience {
  display: grid;
  gap: var(--space-md);
  align-content: start;
}

.audience__title {
  font-size: var(--font-size-xl);
}

.audience__text {
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-muted);
}

.audience .button {
  justify-self: start;
  margin-top: var(--space-sm);
}

/* ---------- Author ---------- */

.author-grid {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: var(--space-3xl);
  align-items: start;
}

.author-photos {
  display: grid;
  gap: var(--space-lg);
}

.portrait {
  position: relative;
}

.portrait__image {
  width: 100%;
  border: 1px solid var(--color-gold-soft);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-lg);
}

.portrait__caption {
  font-size: var(--font-size-xs);
  color: var(--color-text-on-dark-muted);
  margin-top: var(--space-sm);
}

.portrait--main .portrait__image {
  border-width: 2px;
}

.author-bio p {
  margin-bottom: var(--space-lg);
  color: var(--color-text-on-dark);
  line-height: var(--line-height-relaxed);
}

.author-bio p:last-child {
  margin-bottom: 0;
}

.author-bio strong {
  color: var(--color-paper);
}

.author-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-xl);
}

.author-links a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-md);
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
  color: var(--color-text-on-dark);
  font-size: var(--font-size-sm);
  font-size: 0;
  text-decoration: none;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.author-links a:hover {
  border-color: var(--color-gold-soft);
  color: var(--color-gold-soft);
}

/* ---------- Horizontal timeline slider ---------- */

.section--ink-deep {
  background-color: var(--color-ink-deep);
  color: var(--color-text-on-dark);
  border-top: 1px solid var(--color-line-dark);
}

.section--ink-deep h2,
.section--ink-deep h3 {
  color: var(--color-paper);
}

.section--ink-deep .eyebrow {
  color: var(--color-gold-soft);
}

.section--ink-deep .section-lead {
  color: var(--color-text-on-dark-muted);
}

.timeline-slider {
  display: grid;
  gap: var(--space-lg);
}

.timeline-viewport {
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding-bottom: var(--space-xs);
  -webkit-overflow-scrolling: touch;
}

.timeline-viewport::-webkit-scrollbar {
  display: none;
}

.timeline-h {
  display: flex;
  gap: var(--space-md);
  min-width: max-content;
  margin: 0;
  padding: var(--space-xs) var(--space-xs) var(--space-sm);
  list-style: none;
}

.timeline-h__item {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  flex: none;
  width: 15.5rem;
  min-height: 10.5rem;
  padding: var(--space-lg);
  background-color: var(--color-ink-soft);
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
  scroll-snap-align: start;
  transition: border-color var(--transition-base), transform var(--transition-base),
    box-shadow var(--transition-base);
}

.timeline-h__item:hover {
  border-color: var(--color-sage);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.timeline-h__item--milestone {
  border-color: var(--color-gold);
}

.timeline-h__item--milestone:hover {
  border-color: var(--color-gold-soft);
}

.timeline-h__year {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gold-soft);
  line-height: var(--line-height-tight);
}

.timeline-h__text {
  font-size: var(--font-size-sm);
  color: var(--color-text-on-dark);
  line-height: var(--line-height-relaxed);
}

.timeline-nav {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

.timeline-progress {
  flex: 1 1 10rem;
  height: 2px;
  background-color: var(--color-line-dark);
  border-radius: 1px;
  overflow: hidden;
}

.timeline-progress__fill {
  display: block;
  width: 100%;
  height: 100%;
  background-color: var(--color-gold);
  transform-origin: left;
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.timeline-dots {
  display: flex;
  gap: 0;
  flex-wrap: wrap;
}

/* 1.5rem hit area (WCAG target size); visual dot rendered via ::after */
.timeline-dot {
  position: relative;
  width: 1.5rem;
  height: 1.5rem;
  padding: 0;
  background-color: transparent;
  border: 0;
}

.timeline-dot::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0.625rem;
  height: 0.625rem;
  transform: translate(-50%, -50%);
  background-color: var(--color-line-dark);
  border-radius: 2px;
  transition: background-color var(--transition-fast);
}

.timeline-dot:hover {
  background-color: transparent;
}

.timeline-dot:hover::after {
  background-color: var(--color-ink-muted);
}

.timeline-dot.is-active::after {
  background-color: var(--color-gold);
}

.timeline-arrows {
  display: flex;
  gap: var(--space-sm);
  margin-left: auto;
}

/* ---------- Stat band ---------- */

.stat-band {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  padding-block: var(--space-xl);
}

.stat {
  text-align: center;
  padding: var(--space-lg) var(--space-md);
  background-color: var(--color-ink-soft);
  border: 1px solid var(--color-line-dark);
  border-radius: var(--border-radius);
}

.stat__value {
  display: block;
  font-family: var(--font-family-heading);
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-gold-soft);
  margin-bottom: var(--space-xs);
}

.stat__label {
  font-size: var(--font-size-sm);
  color: var(--color-text-on-dark-muted);
}

/* ---------- Work cards (other books) ---------- */

.work-card {
  display: flex;
  gap: var(--space-lg);
  align-items: flex-start;
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  padding: var(--space-lg);
  box-shadow: var(--shadow-sm);
}

.work-card__cover {
  flex: none;
  width: 4.75rem;
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
}

.work-card__badge {
  display: inline-block;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-gold);
  margin-bottom: var(--space-xs);
}

.work-card__title {
  font-size: var(--font-size-md);
  margin-bottom: var(--space-xs);
}

.work-card__meta {
  display: block;
  font-size: var(--font-size-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-sage-deep);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-sm);
}

.work-card__description {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: var(--line-height-relaxed);
}

/* ---------- Buy cards ---------- */

.buy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.buy-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  padding: var(--space-xl) var(--space-lg);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-base), box-shadow var(--transition-base),
    border-color var(--transition-base);
}

.buy-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-sage-deep);
}

.buy-card--featured {
  border-color: var(--color-sage-deep);
  border-top: 3px solid var(--color-sage-deep);
  background-color: var(--color-paper);
}

.buy-card__head {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.buy-card__stamp {
  flex: none;
  width: 2.75rem;
  height: 2.75rem;
  display: grid;
  place-items: center;
  background-color: var(--color-sage-tint);
  border: 1px solid var(--color-sage-deep);
  border-radius: var(--border-radius);
  color: var(--color-sage-dark);
  font-weight: var(--font-weight-bold);
  font-size: var(--font-size-md);
}

.buy-card__name {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.buy-card__tag {
  display: block;
  font-family: var(--font-family-base);
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  font-weight: var(--font-weight-medium);
}

.buy-card__price {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
}

.buy-card__price strong {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-lg);
  color: var(--color-ink);
}

.buy-card__action {
  margin-top: auto;
}

.buy-note {
  margin-top: var(--space-xl);
  padding: var(--space-lg);
  background-color: var(--color-sage-tint);
  border: 1px solid var(--color-sage-deep);
  border-radius: var(--border-radius);
  font-size: var(--font-size-sm);
  color: var(--color-sage-dark);
  line-height: var(--line-height-relaxed);
}

/* ---------- FAQ accordion ---------- */

.faq {
  display: grid;
  gap: var(--space-md);
  max-width: 50rem;
  margin-inline: auto;
}

.faq-item {
  background-color: var(--color-paper-dim);
  border: 1px solid var(--color-line);
  border-radius: var(--border-radius);
  overflow: hidden;
}

.faq-item__question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  width: 100%;
  min-height: 3.5rem;
  padding: var(--space-md) var(--space-lg);
  background-color: transparent;
  border: 0;
  text-align: left;
  font-family: var(--font-family-heading);
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
  color: var(--color-ink);
  transition: background-color var(--transition-fast);
}

.faq-item__question:hover {
  background-color: var(--color-paper-alt);
}

.faq-item__icon {
  flex: none;
  transition: transform var(--transition-base);
  color: var(--color-sage-deep);
}

.faq-item.is-open .faq-item__icon {
  transform: rotate(180deg);
}

.faq-item__panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows var(--transition-base);
}

.faq-item.is-open .faq-item__panel {
  grid-template-rows: 1fr;
}

.faq-item__panel-inner {
  overflow: hidden;
}

.faq-item__answer {
  padding: 0 var(--space-lg) var(--space-lg);
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-muted);
}

/* ---------- CTA band ---------- */

.cta-band {
  background-color: var(--color-ink);
  color: var(--color-text-on-dark);
}

.cta-band__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2xl);
  flex-wrap: wrap;
  padding-block: var(--space-3xl);
}

.cta-band__title {
  font-size: var(--font-size-2xl);
  color: var(--color-paper);
  margin-bottom: var(--space-sm);
}

.cta-band__text {
  color: var(--color-text-on-dark-muted);
  max-width: 34rem;
}

/* ---------- Footer ---------- */

.site-footer {
  background-color: var(--color-ink-deep);
  color: var(--color-text-on-dark);
  padding-top: var(--space-3xl);
}

.site-footer a {
  color: var(--color-text-on-dark);
}

.site-footer a:hover {
  color: var(--color-gold-soft);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2.2fr 1fr 1fr 1.2fr;
  gap: var(--space-2xl);
  padding-bottom: var(--space-2xl);
}

.footer-brand__title {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-xl);
  color: var(--color-paper);
  margin-bottom: var(--space-sm);
}

.footer-brand__text {
  font-size: var(--font-size-sm);
  color: var(--color-text-on-dark-muted);
  line-height: var(--line-height-relaxed);
  max-width: 22rem;
}

.footer-heading {
  font-size: var(--font-size-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-gold-soft);
  margin-bottom: var(--space-md);
  font-family: var(--font-family-base);
  font-weight: var(--font-weight-semibold);
}

.footer-list {
  display: grid;
  gap: var(--space-sm);
}

.footer-list a {
  font-size: var(--font-size-sm);
  text-decoration: none;
}

.footer-list a svg {
  display: inline-block;
  vertical-align: -0.2em;
  margin-right: var(--space-xs);
  color: var(--color-sage);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
  padding-block: var(--space-lg);
  border-top: 1px solid var(--color-line-dark);
  font-size: var(--font-size-xs);
  color: var(--color-text-on-dark-muted);
}

/* ---------- Back to top ---------- */

.to-top {
  position: fixed;
  right: var(--space-lg);
  bottom: var(--space-lg);
  z-index: var(--z-overlay);
  background-color: var(--color-sage-deep);
  color: #ffffff;
  border: 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.5rem);
  transition: opacity var(--transition-base), transform var(--transition-base),
    visibility var(--transition-base), background-color var(--transition-fast);
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.to-top:hover {
  background-color: var(--color-sage-dark);
}

/* ---------- Reveal on scroll ---------- */

.reveal {
  opacity: 0;
  transform: translateY(1.5rem);
  transition: opacity 600ms ease, transform 600ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/**
 * 6. Utilities (helper classes)
 */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

.text-center {
  text-align: center;
}

.no-margin {
  margin: 0;
}

/**
 * 7. Media queries (responsive overrides)
 */

/* Extra large devices (wide desktops) */
@media (max-width: 75rem) {
  .hero__inner {
    gap: var(--space-2xl);
  }

  .book-grid,
  .author-grid {
    gap: var(--space-2xl);
  }
}

/* Large devices (desktops) */
@media (max-width: 62rem) {
  :root {
    --header-height: 4rem;
  }

  .site-nav {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .mobile-nav {
    display: none;
    background-color: var(--color-ink);
    border-top: 1px solid var(--color-line-dark);
    padding: var(--space-md) 0 var(--space-lg);
  }

  .mobile-nav.is-open {
    display: block;
  }

  .mobile-nav__link {
    display: block;
    padding: var(--space-md) var(--space-md);
    color: var(--color-text-on-dark);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    border-radius: var(--border-radius);
  }

  .mobile-nav__link:hover {
    background-color: var(--color-ink-soft);
    color: var(--color-gold-soft);
  }

  .hero__inner {
    grid-template-columns: 1fr;
    padding-block: var(--space-3xl);
  }

  .book-stage {
    order: -1;
    padding-top: 0;
  }

  .book-visual {
    width: min(16rem, 60%);
  }

  /* ID selector here must match the base-rule specificity of
     `#kitap .book-grid` so the single-column rule wins on small screens */
  .book-grid,
  #kitap .book-grid,
  .author-grid {
    grid-template-columns: 1fr;
  }

  .backcover-figure {
    position: static;
  }

  .grid--three,
  .grid--four,
  .buy-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .fact-strip__inner,
  .stat-band {
    grid-template-columns: repeat(2, 1fr);
  }

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

/* Medium devices (tablets) */
@media (max-width: 48rem) {
  .section {
    padding-block: var(--space-3xl);
  }

  .hero__title {
    font-size: var(--font-size-4xl);
  }

  .hero__hook {
    font-size: var(--font-size-md);
  }

  .grid--two,
  .grid--three,
  .grid--four,
  .buy-grid {
    grid-template-columns: 1fr;
  }

  .book-page {
    padding: var(--space-xl) var(--space-lg);
  }

  .note-card__text {
    font-size: var(--font-size-xl);
  }

  .cta-band__inner {
    padding-block: var(--space-2xl);
  }
}

/* Small devices (landscape phones) */
@media (max-width: 36rem) {
  .hero__title {
    font-size: var(--font-size-3xl);
  }

  .hero__actions .button {
    width: 100%;
  }

  .hero__meta li {
    display: block;
    width: 100%;
    margin-left: 0;
  }

  .hero__meta li + li {
    margin-left: 0;
    margin-top: var(--space-sm);
  }

  .fact-strip__inner,
  .stat-band,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .work-card {
    flex-direction: column;
  }

  .site-header__actions .button {
    display: none;
  }

  .to-top {
    right: var(--space-md);
    bottom: var(--space-md);
  }
}

/* Reduced motion: disable non-essential motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .book-stage__trace path {
    stroke-dashoffset: 0;
  }
}