:root {
  --font-sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --color-bg: #f6fbfd;
  --color-surface: #ffffff;
  --color-surface-strong: #edf8fb;
  --color-text: #10232b;
  --color-muted: #58727c;
  --color-border: rgba(16, 35, 43, 0.14);
  --color-primary: #00b4d8;
  --color-primary-strong: #0077b6;
  --color-accent: #ffb703;
  --color-coral: #fb6f59;
  --shadow-soft: 0 24px 70px rgba(4, 50, 68, 0.14);
  --shadow-card: 0 16px 45px rgba(4, 50, 68, 0.11);
  --radius: 8px;
}

[data-theme="dark"] {
  --color-bg: #07151b;
  --color-surface: #0d222b;
  --color-surface-strong: #12313d;
  --color-text: #eefaff;
  --color-muted: #a8c4cd;
  --color-border: rgba(218, 245, 255, 0.16);
  --color-primary: #48cae4;
  --color-primary-strong: #90e0ef;
  --color-accent: #ffd166;
  --color-coral: #ff8d75;
  --shadow-soft: 0 24px 70px rgba(0, 0, 0, 0.35);
  --shadow-card: 0 16px 45px rgba(0, 0, 0, 0.28);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--color-text);
  background:
    radial-gradient(circle at 8% 0%, rgba(0, 180, 216, 0.14), transparent 26rem),
    linear-gradient(180deg, var(--color-bg), var(--color-surface-strong));
  font-family: var(--font-sans);
  line-height: 1.65;
}

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

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

svg {
  width: 1.15rem;
  height: 1.15rem;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
}

.container {
  width: min(1120px, calc(100% - 2rem));
  margin-inline: auto;
}

.narrow {
  max-width: 760px;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 100;
  transform: translateY(-160%);
  padding: 0.65rem 0.85rem;
  border-radius: var(--radius);
  color: #001219;
  background: var(--color-accent);
  font-weight: 800;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid var(--color-border);
  background: color-mix(in srgb, var(--color-bg) 86%, transparent);
  backdrop-filter: blur(18px);
}

.header-shell {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  min-height: 78px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.72rem;
  font-weight: 900;
  transform-origin: left center;
  transition: transform 180ms ease;
}

.brand:hover,
.brand:focus-visible {
  transform: translateY(-0.15rem) rotate(-1deg);
}

.brand-badge {
  display: grid;
  place-items: center;
  width: 3.05rem;
  height: 3.05rem;
  border-radius: 50%;
  color: #001219;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  box-shadow: 0 14px 30px rgba(0, 119, 182, 0.22);
  letter-spacing: 0;
  transition: box-shadow 180ms ease;
}

.brand:hover .brand-badge,
.brand:focus-visible .brand-badge {
  box-shadow: 0 18px 34px rgba(0, 119, 182, 0.28);
}

.brand-text {
  font-size: clamp(1.2rem, 2vw, 1.55rem);
}

.header-actions {
  display: flex;
  grid-column: 3;
  align-items: center;
  justify-content: flex-end;
  gap: 0.5rem;
}

.site-nav {
  grid-column: 2;
  grid-row: 1;
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.menu-root,
.submenu {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-tools {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.menu-item {
  position: relative;
}

.menu-item > a {
  display: inline-flex;
  align-items: center;
  gap: 0.42rem;
  min-height: 2.6rem;
  padding: 0.52rem 0.72rem;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--color-muted);
  font-size: 0.9rem;
  font-weight: 800;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
}

.menu-item > a:hover,
.menu-item > a:focus-visible,
.menu-item-active > a {
  color: var(--color-text);
  border-color: color-mix(in srgb, var(--color-primary) 65%, var(--color-border));
  background: var(--color-surface-strong);
}

.menu-item > a:hover,
.menu-item > a:focus-visible {
  transform: translateY(-0.1rem);
}

.menu-icon {
  display: inline-flex;
}

.submenu {
  position: absolute;
  top: 100%;
  left: 0;
  display: none;
  min-width: 15rem;
  flex-direction: column;
  align-items: stretch;
  padding: 0.55rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.menu-item-has-children:hover > .submenu,
.menu-item-has-children:focus-within > .submenu {
  display: flex;
}

.submenu a {
  justify-content: flex-start;
  width: 100%;
}

.icon-button {
  display: inline-grid;
  place-items: center;
  width: 2.6rem;
  height: 2.6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  color: var(--color-muted);
  background: var(--color-surface);
  cursor: pointer;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
}

.icon-button:hover,
.icon-button:focus-visible,
.icon-button[aria-checked="true"] {
  color: var(--color-text);
  border-color: color-mix(in srgb, var(--color-primary) 65%, var(--color-border));
  background: var(--color-surface-strong);
}

.icon-button:hover,
.icon-button:focus-visible {
  transform: translateY(-0.1rem);
}

.theme-toggle {
  display: inline-flex;
  gap: 0.25rem;
  padding: 0.2rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
}

.theme-toggle .icon-button {
  width: 2.1rem;
  height: 2.1rem;
  border-color: transparent;
}

.theme-toggle .icon-button:hover,
.theme-toggle .icon-button:focus-visible,
.theme-toggle .icon-button[aria-checked="true"] {
  border-color: color-mix(in srgb, var(--color-primary) 65%, var(--color-border));
}

.language-switcher {
  display: inline-flex;
  gap: 0.25rem;
  overflow: visible;
  padding: 0.2rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
}

.language-option {
  display: inline-grid;
  place-items: center;
  width: 2.1rem;
  height: 2.1rem;
  padding: 0;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--color-muted);
  background: var(--color-surface);
  font-size: 1.15rem;
  font-weight: 900;
  text-align: center;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
}

.language-flag {
  line-height: 1;
}

.language-option-active,
.language-option:hover,
.language-option:focus-visible {
  color: var(--color-text);
  border-color: color-mix(in srgb, var(--color-primary) 65%, var(--color-border));
  background: var(--color-surface-strong);
}

.language-option:hover,
.language-option:focus-visible {
  transform: translateY(-0.1rem);
}

.menu-toggle,
.menu-close {
  display: none;
}

.hero-section,
.page-hero,
.book-hero {
  padding: clamp(4rem, 8vw, 7.5rem) 0 clamp(3rem, 5vw, 5rem);
}

.hero-section {
  padding-block: clamp(2rem, 4vw, 4rem);
}

.hero-grid,
.books-showcase {
  padding: clamp(1.5rem, 4vw, 3rem);
}

.hero-grid {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 2);
  background:
    radial-gradient(circle at 92% 8%, color-mix(in srgb, var(--color-accent) 24%, transparent), transparent 18rem),
    radial-gradient(circle at 76% 100%, color-mix(in srgb, var(--color-primary) 18%, transparent), transparent 24rem),
    var(--color-surface);
  box-shadow: var(--shadow-soft);
}

.hero-copy {
  position: relative;
  z-index: 1;
  max-width: none;
}

.hero-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(210px, 260px);
  align-items: center;
  gap: clamp(2rem, 4vw, 4rem);
}

.eyebrow {
  margin: 0 0 0.7rem;
  color: var(--color-primary-strong);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.05;
  letter-spacing: 0;
}

h1 {
  max-width: 13ch;
  font-size: clamp(2.7rem, 6vw, 5.7rem);
}

.hero-copy h1 {
  max-width: 18ch;
  font-size: clamp(3.25rem, 5vw, 4.75rem);
  line-height: 0.98;
  letter-spacing: -0.035em;
}

.hero-portrait-trigger {
  position: relative;
  z-index: 1;
  display: block;
  width: min(100%, 260px);
  justify-self: end;
  padding: 0.55rem;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 1.5);
  color: var(--color-text);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  cursor: zoom-in;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.hero-portrait-trigger:hover {
  transform: translateY(-0.25rem);
  box-shadow: var(--shadow-soft);
}

.hero-portrait-trigger:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 4px;
}

.hero-portrait-trigger img {
  width: 100%;
  height: clamp(16rem, 24vw, 20rem);
  border-radius: var(--radius);
  object-fit: cover;
  object-position: center 18%;
}

.hero-portrait-hint {
  position: absolute;
  right: 1rem;
  bottom: 1rem;
  left: 1rem;
  transform: translateY(calc(100% + 1.2rem));
  padding: 0.45rem 0.65rem;
  border-radius: var(--radius);
  color: #ffffff;
  background: rgba(7, 21, 27, 0.78);
  font-size: 0.78rem;
  font-weight: 800;
  opacity: 0;
  text-align: center;
  backdrop-filter: blur(8px);
  transition: transform 180ms ease, opacity 180ms ease;
}

.hero-portrait-trigger:hover .hero-portrait-hint,
.hero-portrait-trigger:focus-visible .hero-portrait-hint,
.book-cover-trigger:hover .hero-portrait-hint,
.book-cover-trigger:focus-visible .hero-portrait-hint {
  transform: translateY(0);
  opacity: 1;
}

.image-lightbox {
  width: fit-content;
  max-width: calc(100vw - 2rem);
  max-height: calc(100vh - 2rem);
  padding: 0;
  overflow: visible;
  border: 0;
  border-radius: calc(var(--radius) * 1.5);
  background: transparent;
}

.image-lightbox::backdrop {
  background: rgba(2, 12, 17, 0.88);
  backdrop-filter: blur(8px);
}

.image-lightbox:target {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  width: 100vw;
  max-width: none;
  height: 100vh;
  max-height: none;
  place-items: center;
  padding: 1rem;
  border-radius: 0;
  background: rgba(2, 12, 17, 0.9);
  backdrop-filter: blur(8px);
}

.image-lightbox img {
  width: auto;
  max-width: calc(100vw - 2rem);
  height: auto;
  max-height: calc(100vh - 2rem);
  border-radius: calc(var(--radius) * 1.5);
  box-shadow: 0 28px 90px rgba(0, 0, 0, 0.5);
}

.image-lightbox-close {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid rgba(255, 255, 255, 0.38);
  border-radius: 50%;
  color: #ffffff;
  background: rgba(7, 21, 27, 0.78);
  font: inherit;
  font-size: 0;
  cursor: pointer;
  text-decoration: none;
  backdrop-filter: blur(8px);
  transition: border-color 160ms ease, background-color 160ms ease, transform 160ms ease;
}

.image-lightbox-close::before {
  width: 1rem;
  height: 1rem;
  background:
    linear-gradient(45deg, transparent 44%, #ffffff 45%, #ffffff 55%, transparent 56%),
    linear-gradient(-45deg, transparent 44%, #ffffff 45%, #ffffff 55%, transparent 56%);
  content: "";
}

.image-lightbox-close:hover,
.image-lightbox-close:focus-visible {
  transform: scale(1.08);
  border-color: #ffffff;
  background: rgba(7, 21, 27, 0.96);
}

.image-lightbox-close:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
}

body.lightbox-open {
  overflow: hidden;
}

.page-hero h1 {
  max-width: 16ch;
}

.about-hero {
  padding: clamp(1.25rem, 3vw, 2.5rem) 0 clamp(2rem, 4vw, 3.5rem);
}

.about-hero-card {
  position: relative;
  overflow: hidden;
  padding: clamp(1.5rem, 4vw, 3.25rem);
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 2.5);
  background:
    radial-gradient(circle at 88% 8%, color-mix(in srgb, var(--color-accent) 36%, transparent), transparent 18rem),
    radial-gradient(circle at 68% 112%, color-mix(in srgb, var(--color-primary) 32%, transparent), transparent 27rem),
    linear-gradient(135deg, var(--color-surface), color-mix(in srgb, var(--color-surface-strong) 78%, var(--color-primary) 22%));
  box-shadow: var(--shadow-soft);
}

.about-hero-card::before {
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(112deg, color-mix(in srgb, var(--color-surface) 34%, transparent), transparent 56%);
  content: "";
  pointer-events: none;
}

.about-watermark {
  position: absolute;
  right: 19%;
  bottom: -0.24em;
  color: color-mix(in srgb, var(--color-primary) 9%, transparent);
  font-size: clamp(9rem, 20vw, 16rem);
  font-weight: 900;
  line-height: 0.8;
  letter-spacing: -0.09em;
  pointer-events: none;
  user-select: none;
}

.about-hero-layout {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 280px);
  align-items: center;
  gap: clamp(2rem, 4vw, 4rem);
}

.about-hero-copy {
  position: relative;
  z-index: 1;
}

.about-hero-copy h1 {
  max-width: none;
  font-size: clamp(3.6rem, 7vw, 6.4rem);
  line-height: 0.9;
  letter-spacing: -0.055em;
}

.about-hero-copy .lead {
  max-width: 54ch;
  color: var(--color-text);
}

.about-portrait-trigger {
  position: relative;
  z-index: 1;
  width: min(100%, 280px);
  transform: rotate(1.5deg);
}

.about-portrait-trigger:hover {
  transform: rotate(0) translateY(-0.25rem);
}

.about-portrait-trigger img {
  height: 22rem;
  object-position: center 18%;
}

.about-fact-strip {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.65rem;
  margin-top: clamp(1.5rem, 4vw, 3rem);
}

.about-fact {
  display: grid;
  gap: 0.15rem;
  min-width: 0;
  padding: 0.85rem 1rem;
  border: 1px solid color-mix(in srgb, var(--color-border) 72%, transparent);
  border-radius: calc(var(--radius) * 1.25);
  background: color-mix(in srgb, var(--color-surface) 72%, transparent);
  backdrop-filter: blur(12px);
}

.about-fact span {
  color: var(--color-muted);
  font-size: 0.7rem;
  font-weight: 800;
  text-transform: uppercase;
}

.about-fact strong {
  overflow: hidden;
  font-size: 0.92rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}

h2 {
  font-size: clamp(2rem, 3.8vw, 3.35rem);
}

h3 {
  font-size: 1.4rem;
}

.lead {
  max-width: 66ch;
  margin: 1.25rem 0 0;
  color: var(--color-muted);
  font-size: clamp(1.08rem, 1.6vw, 1.25rem);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.8rem;
}

.button {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  min-height: 2.9rem;
  padding: 0.72rem 1rem;
  overflow: hidden;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-weight: 900;
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.button::before {
  position: absolute;
  inset: -1px;
  transform: translateX(-115%) skewX(-18deg);
  background: linear-gradient(100deg, transparent 20%, rgba(255, 255, 255, 0.42), transparent 80%);
  content: "";
  pointer-events: none;
  transition: transform 520ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-0.2rem);
  border-color: color-mix(in srgb, var(--color-primary-strong) 35%, transparent);
  box-shadow: var(--shadow-card);
}

.button:hover::before,
.button:focus-visible::before {
  transform: translateX(115%) skewX(-18deg);
}

.button svg,
.button > span {
  position: relative;
}

.button svg {
  transition: transform 180ms ease;
}

.button:hover svg,
.button:focus-visible svg {
  transform: translateX(0.2rem);
}

.button-primary {
  color: #001219;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  box-shadow: 0 14px 30px rgba(0, 119, 182, 0.22);
}

.button-secondary {
  color: var(--color-text);
  border-color: var(--color-border);
  background: var(--color-surface);
}

.book-card-cover img,
.book-cover-large {
  width: 100%;
  border-radius: 6px;
  box-shadow: var(--shadow-soft);
}

.section {
  padding: clamp(3rem, 6vw, 6rem) 0;
}

.books-section {
  padding-top: 0;
}

.books-showcase {
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 2);
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--color-surface-strong) 72%, transparent), var(--color-surface));
  box-shadow: var(--shadow-card);
}

.section-topless {
  padding-top: 0;
}

.section-head {
  max-width: 720px;
  margin-bottom: 2rem;
}

.section-head p:not(.eyebrow) {
  color: var(--color-muted);
}

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

.book-card {
  display: grid;
  grid-template-rows: auto 1fr;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.book-card:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
}

.book-card-cover {
  display: grid;
  place-items: center;
  padding: 1.25rem;
  background:
    linear-gradient(135deg, rgba(0, 180, 216, 0.2), rgba(255, 183, 3, 0.18)),
    var(--color-surface-strong);
}

.book-card-cover img {
  max-width: 210px;
  transition: transform 240ms ease, filter 240ms ease;
}

.book-card-cover:hover img,
.book-card-cover:focus-visible img {
  transform: translateY(-0.2rem) scale(1.02);
  filter: saturate(1.06);
}

.book-card-body {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  padding: 1.1rem;
}

.book-card-body p {
  margin: 0;
  color: var(--color-muted);
}

.book-card-meta,
.book-meta-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.book-card-meta span,
.book-meta-list span {
  padding: 0.26rem 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  color: var(--color-muted);
  font-size: 0.78rem;
  font-weight: 800;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: auto;
  color: var(--color-primary-strong);
  font-weight: 900;
}

.text-link svg {
  transition: transform 160ms ease;
}

.text-link:hover,
.text-link:focus-visible,
.back-link:hover,
.back-link:focus-visible,
.prose a:hover,
.prose a:focus-visible,
.contact-email-link:hover,
.contact-email-link:focus-visible {
  color: var(--color-coral);
}

.text-link:hover svg,
.text-link:focus-visible svg {
  transform: translateX(0.2rem);
}

.book-hero-grid {
  display: grid;
  grid-template-columns: minmax(220px, 360px) minmax(0, 1fr);
  align-items: center;
  gap: clamp(2rem, 5vw, 4rem);
}

.book-cover-panel {
  padding: 1.1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: transparent;
}

.book-cover-large {
  display: block;
  max-height: 560px;
  border-radius: inherit;
  object-fit: contain;
  box-shadow: none;
}

.book-cover-trigger {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: var(--radius);
  cursor: zoom-in;
}

.book-cover-trigger .book-cover-large {
  transition: transform 240ms ease, filter 240ms ease;
}

.book-cover-trigger:hover .book-cover-large,
.book-cover-trigger:focus-visible .book-cover-large {
  transform: scale(1.025);
  filter: saturate(1.06);
}

.book-cover-trigger:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 4px;
}

.book-hero-copy h1 {
  max-width: 12ch;
}

.book-hero-copy .book-meta-list {
  margin-top: 0.75rem;
}

.book-hero-copy .button-row .button {
  flex: 1 1 10rem;
}

.back-link {
  display: inline-flex;
  margin-bottom: 1rem;
  color: var(--color-primary-strong);
  font-weight: 900;
}

.small-note {
  max-width: 60ch;
  margin: 0.85rem 0 0;
  color: var(--color-muted);
  font-size: 0.9rem;
}

.book-details-grid {
  display: grid;
  grid-template-columns: 1fr;
  align-items: start;
  gap: 1.5rem;
}

.prose {
  color: var(--color-text);
  font-size: 1.04rem;
}

.prose h2 {
  margin-top: 2.2rem;
  margin-bottom: 0.8rem;
  font-size: clamp(1.55rem, 2.5vw, 2.2rem);
}

.prose h2:first-child {
  margin-top: 0;
}

.prose p,
.prose li {
  color: var(--color-muted);
}

.prose a {
  color: var(--color-primary-strong);
  font-weight: 800;
  text-decoration: underline;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

.about-chapter-section {
  padding-top: 0;
}

.about-section-intro {
  width: 100%;
  margin-bottom: clamp(1.5rem, 4vw, 2.75rem);
}

.about-section-intro h2 {
  max-width: none;
}

.about-section-intro > p:last-child {
  max-width: none;
  color: var(--color-muted);
  font-size: 1.08rem;
}

.about-chapters {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.about-chapter {
  position: relative;
  overflow: hidden;
  padding: clamp(1.5rem, 3vw, 2.35rem);
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 2);
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--color-surface) 94%, var(--color-primary) 6%), var(--color-surface));
  box-shadow: var(--shadow-card);
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.about-chapter::before {
  position: absolute;
  inset: 0 0 auto;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  content: "";
}

.about-chapter:hover {
  transform: translateY(-0.2rem);
  box-shadow: var(--shadow-soft);
}

.about-chapter-wide {
  grid-column: auto;
}

.about-chapter-head {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.about-chapter-head .eyebrow {
  margin-bottom: 0.35rem;
}

.about-chapter-number {
  color: color-mix(in srgb, var(--color-primary) 45%, var(--color-text));
  font-size: clamp(2.7rem, 5vw, 4.1rem);
  font-weight: 900;
  line-height: 0.88;
  letter-spacing: -0.07em;
}

.about-chapter h2 {
  font-size: clamp(1.55rem, 2.7vw, 2.35rem);
}

.about-chapter > p {
  margin: 0.8rem 0 0;
  color: var(--color-muted);
}

.about-chapter-intro {
  max-width: 76ch;
  font-size: 1.05rem;
}

.about-timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.about-timeline-stop,
.about-book-note {
  padding: 1rem;
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 1.25);
  background: var(--color-surface-strong);
}

.about-book-note {
  display: block;
  color: inherit;
  text-decoration: none;
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    box-shadow 160ms ease;
}

.about-book-note:hover,
.about-book-note:focus-visible {
  transform: translateY(-2px);
  border-color: color-mix(in srgb, var(--color-primary) 55%, var(--color-border));
  box-shadow: var(--shadow-soft);
}

.about-timeline-stop {
  display: grid;
  align-content: start;
  gap: 0.25rem;
}

.about-timeline-stop time {
  color: var(--color-primary-strong);
  font-size: 1.65rem;
  font-weight: 900;
}

.about-timeline-stop strong {
  color: var(--color-text);
}

.about-timeline-stop p,
.about-book-notes p {
  margin: 0.35rem 0 0;
  color: var(--color-muted);
  font-size: 0.9rem;
  line-height: 1.5;
}

.about-book-notes {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.about-book-notes h3 {
  font-size: 1.05rem;
}

.about-platform-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.about-platform-grid a {
  display: grid;
  gap: 0.55rem;
  padding: 1rem;
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 1.25);
  background: var(--color-surface-strong);
  transition: border-color 180ms ease, transform 180ms ease;
}

.about-platform-grid a:hover,
.about-platform-grid a:focus-visible {
  transform: translateY(-0.18rem);
  border-color: var(--color-primary);
}

.about-platform-grid a > span:last-child {
  color: var(--color-muted);
  font-size: 0.9rem;
  line-height: 1.5;
}

.about-card-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  color: var(--color-text);
  font-weight: 900;
}

.about-card-arrow {
  display: inline-grid;
  flex: 0 0 1.75rem;
  width: 1.75rem;
  height: 1.75rem;
  place-items: center;
  border-radius: 999px;
  background: color-mix(in srgb, var(--color-primary) 14%, transparent);
  color: var(--color-primary-strong);
  font-size: 1rem;
  line-height: 1;
  transition: transform 160ms ease, background-color 160ms ease;
}

.contact-hero-layout {
  grid-template-columns: minmax(0, 1fr) minmax(280px, 350px);
}

.contact-watermark {
  right: 15%;
  bottom: -0.12em;
  font-size: clamp(12rem, 25vw, 21rem);
  letter-spacing: -0.04em;
}

.contact-hero-address {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 0.45rem;
  min-width: 0;
  padding: clamp(1.35rem, 3vw, 2rem);
  transform: rotate(1.25deg);
  border: 1px solid color-mix(in srgb, var(--color-primary) 45%, var(--color-border));
  border-radius: calc(var(--radius) * 2);
  background: color-mix(in srgb, var(--color-surface) 88%, transparent);
  box-shadow: var(--shadow-card);
  color: var(--color-text);
  text-decoration: none;
  backdrop-filter: blur(14px);
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.contact-hero-address:hover,
.contact-hero-address:focus-visible {
  transform: rotate(0) translateY(-0.25rem);
  border-color: var(--color-primary);
  box-shadow: var(--shadow-soft);
}

.contact-address-symbol {
  color: var(--color-primary-strong);
  font-size: clamp(3rem, 6vw, 4.5rem);
  font-weight: 900;
  line-height: 0.85;
}

.contact-address-label {
  color: var(--color-muted);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.contact-hero-address strong {
  overflow-wrap: anywhere;
  font-size: clamp(1.1rem, 2vw, 1.35rem);
}

.contact-address-hint {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 0.55rem;
  color: var(--color-primary-strong);
  font-size: 0.9rem;
  font-weight: 800;
}

.contact-detail-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.contact-detail-grid .about-chapter {
  height: 100%;
}

.contact-email-link {
  display: inline-block;
  margin-top: 1.35rem;
  color: var(--color-primary-strong);
  font-size: clamp(1.25rem, 2.7vw, 2rem);
  font-weight: 900;
  overflow-wrap: anywhere;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

.contact-link-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.about-book-note:hover .about-card-arrow,
.about-book-note:focus-visible .about-card-arrow,
.about-platform-grid a:hover .about-card-arrow,
.about-platform-grid a:focus-visible .about-card-arrow {
  transform: translateX(2px);
  background: color-mix(in srgb, var(--color-primary) 23%, transparent);
}

.standout {
  padding: 1.1rem;
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius) var(--radius) 0;
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.book-samples-card {
  position: sticky;
  top: 6rem;
}

.book-samples-card .about-chapter-head {
  margin-bottom: 0.8rem;
}

.book-highlights-list {
  display: grid;
  gap: 0.75rem;
  margin: 0;
  padding-left: 1.2rem;
  color: var(--color-muted);
}

.book-highlights-list li::marker {
  color: var(--color-primary-strong);
}

.sample-list {
  display: grid;
  gap: 1.25rem;
  margin-top: 1rem;
}

.sample-intro {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.95rem;
}

.sample-card {
  margin: 0;
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 1.25);
  background: var(--color-surface-strong);
  transition: border-color 160ms ease, box-shadow 160ms ease;
}

.sample-card summary {
  display: grid;
  gap: 0.3rem;
  padding: 1rem;
  cursor: pointer;
  list-style: none;
  transition: background-color 160ms ease;
}

.sample-card summary:hover,
.sample-card summary:focus-visible {
  background: color-mix(in srgb, var(--color-primary) 9%, transparent);
}

.sample-card:hover {
  border-color: color-mix(in srgb, var(--color-primary) 55%, var(--color-border));
  box-shadow: 0 8px 24px color-mix(in srgb, var(--color-primary) 12%, transparent);
}

.sample-card summary::-webkit-details-marker {
  display: none;
}

.sample-card-label {
  margin: 0;
  color: var(--color-primary-strong);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.sample-card-title {
  padding-right: 1.5rem;
  color: var(--color-text);
  font-weight: 900;
}

.sample-card-text {
  padding: 0 1rem 1rem;
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.sample-card-text p {
  margin: 0.9rem 0 0;
}

.sample-card-text p + p {
  margin-top: 0.9rem;
}

.sample-card-text p:last-child {
  margin-bottom: 0;
}

.sample-card:focus-within {
  border-color: color-mix(in srgb, var(--color-primary) 55%, var(--color-border));
}

.sample-card summary:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--color-primary) 55%, transparent);
  outline-offset: -3px;
}

.sample-card h3 {
  font-size: 1.15rem;
}

.standard-page {
  min-height: 60vh;
}

.search-stage {
  position: relative;
  min-height: 34rem;
  padding: clamp(4rem, 8vw, 7rem) 0 clamp(4rem, 8vw, 7rem);
  overflow: hidden;
  border-bottom: 1px solid var(--color-border);
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--color-primary) 10%, transparent), transparent 48%),
    linear-gradient(315deg, color-mix(in srgb, var(--color-accent) 10%, transparent), transparent 42%);
}

.search-shell {
  position: relative;
}

.search-intro {
  max-width: 52rem;
}

.search-intro h1 {
  max-width: none;
  font-size: clamp(3.75rem, 8vw, 6.5rem);
}

.search-intro .lead {
  max-width: 48rem;
}

.not-found-panel {
  display: grid;
  grid-template-columns: minmax(10rem, 0.45fr) minmax(0, 1.55fr);
  align-items: center;
  gap: clamp(3rem, 7vw, 6rem);
  padding: clamp(2rem, 5vw, 4.5rem);
  border: 1px solid var(--color-border);
  border-radius: calc(var(--radius) * 2);
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--color-surface-strong) 86%, transparent), var(--color-surface));
  box-shadow: var(--shadow-soft);
}

.not-found-code {
  min-width: 0;
  margin: 0;
  transform: translateX(-1.25rem);
  color: var(--color-primary-strong);
  font-size: clamp(6.5rem, 11vw, 8.5rem);
  font-weight: 950;
  line-height: 0.8;
  text-align: left;
}

.not-found-copy h1 {
  max-width: 13ch;
  font-size: clamp(2.6rem, 4vw, 4rem);
  overflow-wrap: break-word;
}

.not-found-copy {
  min-width: 0;
  padding-left: clamp(1rem, 2vw, 2rem);
  border-left: 1px solid var(--color-border);
}

.not-found-copy .lead {
  max-width: 44rem;
}

.not-found-copy .button-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 16rem));
}

.not-found-copy .button {
  width: 100%;
  white-space: nowrap;
}

.search-workspace {
  width: min(100%, 62rem);
  margin-top: clamp(2rem, 4vw, 3rem);
}

.search-form {
  position: relative;
  display: block;
}

.search-form input {
  width: 100%;
  min-height: 4.25rem;
  padding: 0.9rem 3.5rem 0.9rem 3.5rem;
  border: 2px solid color-mix(in srgb, var(--color-primary) 38%, var(--color-border));
  border-radius: var(--radius);
  color: var(--color-text);
  background: var(--color-surface);
  font: inherit;
  font-size: 1.08rem;
  box-shadow: var(--shadow-card);
}

.search-form input:focus-visible {
  border-color: var(--color-primary);
  outline: 3px solid color-mix(in srgb, var(--color-primary) 24%, transparent);
}

.search-form input::-webkit-search-cancel-button {
  display: none;
  width: 0;
  height: 0;
  -webkit-appearance: none;
  appearance: none;
}

.search-form input::-ms-clear,
.search-form input::-ms-reveal {
  display: none;
  width: 0;
  height: 0;
}

.search-field-icon,
.search-clear {
  position: absolute;
  top: 50%;
  z-index: 1;
  display: inline-grid;
  place-items: center;
  transform: translateY(-50%);
  color: var(--color-muted);
}

.search-field-icon {
  left: 1.2rem;
  pointer-events: none;
}

.search-field-icon svg {
  width: 1.4rem;
  height: 1.4rem;
}

.search-clear {
  right: 1rem;
  width: 2.25rem;
  height: 2.25rem;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.search-feedback {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  min-height: 3rem;
  padding: 0.75rem 0.25rem;
}

.search-feedback-mark {
  display: inline-flex;
  color: var(--color-primary-strong);
}

.search-status {
  margin: 0;
  color: var(--color-muted);
  font-weight: 700;
}

.search-results {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  width: min(100%, 62rem);
}

.search-result {
  padding: 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.search-result h2 {
  font-size: 1.35rem;
}

.search-result a:hover,
.search-result a:focus-visible {
  color: var(--color-primary-strong);
}

.search-result p {
  margin: 0.55rem 0 0;
  color: var(--color-muted);
}

.site-footer {
  margin-top: 2rem;
  padding: 3rem 0 1.25rem;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2rem;
}

.footer-grid h2 {
  margin-bottom: 0.85rem;
  font-size: 0.9rem;
  text-transform: uppercase;
}

.footer-grid p,
.copyright {
  color: var(--color-muted);
}

.footer-grid a:hover {
  color: var(--color-primary-strong);
}

.footer-brand {
  margin-bottom: 0.75rem;
}

.copyright {
  width: min(1120px, calc(100% - 2rem));
  margin: 2rem auto 0;
  font-size: 0.9rem;
}

@media (max-width: 980px) {
  .header-shell {
    grid-template-columns: auto 1fr;
  }

  .site-nav {
    grid-column: 1 / -1;
    justify-self: stretch;
    display: flex;
  }

  .menu-toggle {
    display: inline-grid;
  }

  .menu-close {
    display: inline-grid;
    align-self: flex-end;
  }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: 60;
    display: flex;
    width: 100%;
    height: 100dvh;
    flex-direction: column;
    align-items: stretch;
    gap: 1.5rem;
    padding: 1.5rem;
    overflow-y: auto;
    transform: translateY(-110%);
    border: 0;
    background-color: var(--color-surface);
    background:
      radial-gradient(circle at 90% 0%, color-mix(in srgb, var(--color-accent) 18%, transparent), transparent 20rem),
      var(--color-surface);
    isolation: isolate;
    box-shadow: var(--shadow-soft);
    transition: transform 180ms ease;
  }

  .menu-open .site-nav {
    transform: translateY(0);
  }

  .nav-tools {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
    margin-top: auto;
    padding-top: 1.5rem;
    border-top: 1px solid var(--color-border);
  }

  .menu-root,
  .submenu {
    position: static;
    display: flex;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    border: 0;
    box-shadow: none;
  }

  .submenu {
    padding: 0 0 0 1rem;
    background: transparent;
  }

  .book-hero-grid,
  .book-details-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .about-fact-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

  .contact-detail-grid {
    grid-template-columns: 1fr;
  }

  .hero-copy h1 {
    max-width: 15ch;
    font-size: clamp(3.25rem, 8vw, 4.75rem);
  }

  .hero-layout {
    grid-template-columns: 1fr;
  }

  .hero-portrait-trigger {
    width: min(100%, 240px);
    justify-self: start;
  }

  .hero-portrait-trigger img {
    height: 17.5rem;
  }

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

  .book-samples-card {
    position: static;
  }
}

@media (max-width: 760px) {
  .about-hero-layout,
  .contact-hero-layout {
    grid-template-columns: 1fr;
  }

  .contact-hero-address {
    width: min(100%, 360px);
    justify-self: start;
  }

  .about-portrait-trigger {
    justify-self: center;
  }

  .about-book-notes,
  .about-platform-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 1rem, 1120px);
  }

  .header-shell {
    min-height: 68px;
  }

  .brand-badge {
    width: 2.55rem;
    height: 2.55rem;
  }

  .brand-text {
    font-size: 1.12rem;
  }

  .header-actions {
    gap: 0.3rem;
  }

  .language-option {
    width: 1.85rem;
    height: 1.85rem;
  }

  .theme-toggle .icon-button {
    width: 1.85rem;
    height: 1.85rem;
  }

  .hero-section,
  .page-hero,
  .book-hero {
    padding-top: 3rem;
  }

  .hero-section {
    padding-top: 1rem;
  }

  .hero-grid,
  .books-showcase,
  .about-hero-card,
  .about-chapter {
    padding: 1.25rem;
    border-radius: var(--radius);
  }

  .about-hero-copy h1 {
    font-size: clamp(2.75rem, 15vw, 4.2rem);
  }

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

  .about-fact:last-child {
    grid-column: 1 / -1;
  }

  .about-timeline {
    grid-template-columns: 1fr;
  }

  h1 {
    font-size: 2.55rem;
  }

  .hero-copy h1 {
    max-width: none;
    font-size: clamp(2.55rem, 12vw, 3.5rem);
    line-height: 1;
  }

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

  .button {
    width: 100%;
  }

  .search-results {
    grid-template-columns: 1fr;
  }

  .search-stage {
    min-height: 30rem;
    padding-top: 3rem;
  }

  .not-found-panel {
    grid-template-columns: minmax(0, 1fr);
    gap: 2rem;
    padding: 2rem 1.25rem;
  }

  .not-found-code {
    transform: none;
    font-size: clamp(6rem, 30vw, 9rem);
    text-align: center;
  }

  .not-found-copy {
    padding-left: 0;
    border-left: 0;
    text-align: center;
  }

  .not-found-copy h1,
  .not-found-copy .lead {
    max-width: none;
  }

  .not-found-copy .button-row {
    grid-template-columns: 1fr;
  }

  .not-found-copy .button {
    gap: 0.35rem;
    padding-inline: 0.5rem;
    font-size: 0.78rem;
  }
}

@media (max-width: 420px) {
  .brand-text {
    display: none;
  }

  .not-found-copy h1 {
    font-size: 1.85rem;
  }
}