:root {
  --color-cyan: #0B6E8A;
  --color-indigo: #102A43;
  --color-orange: #F28A2E;
  --color-gold: #C99A3D;
  --color-snow: #F7FAFC;
  --color-mist: #DDE8EC;
  --color-ink: #071923;
  --color-teal: #2BA89A;
  --color-sand: #F3E4C8;
  --color-electric: #3FD0C9;
  --font-heading: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-numeric: "Inter", "SFMono-Regular", "Cascadia Mono", "Roboto Mono", monospace;
  --gutter: clamp(1rem, 4vw, 3rem);
  --layout-max: 1200px;
  --radius-pill: 999px;
  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 14px;
  --shadow-island: 0 18px 48px rgba(7, 25, 35, 0.12), inset 0 1px 0 rgba(255, 255, 255, 0.74);
  --shadow-card: 0 16px 38px rgba(7, 25, 35, 0.07);
  --hairline: 1px solid rgba(16, 42, 67, 0.14);
  --ease: cubic-bezier(0.2, 0.75, 0.25, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 132px;
}

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--color-ink);
  background-color: var(--color-snow);
  background-image:
    radial-gradient(circle at 7% 4%, rgba(11, 110, 138, 0.08), transparent 30rem),
    radial-gradient(circle at 96% 16%, rgba(242, 138, 46, 0.06), transparent 24rem),
    linear-gradient(90deg, rgba(16, 42, 67, 0.018) 1px, transparent 1px),
    linear-gradient(rgba(16, 42, 67, 0.018) 1px, transparent 1px);
  background-size: auto, auto, 64px 64px, 64px 64px;
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: 0.01em;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body,
button,
input,
textarea,
select {
  font-family: var(--font-sans);
}

h1,
h2,
h3,
h4,
p,
figure,
blockquote,
dl,
dd {
  margin: 0;
}

h1,
h2,
h3,
h4 {
  text-wrap: balance;
}

h1,
h2 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: 0.01em;
  color: var(--color-indigo);
}

h1 {
  font-size: clamp(2.6rem, 6vw, 5.6rem);
  line-height: 1.06;
}

h2 {
  font-size: clamp(1.8rem, 3.5vw, 3rem);
}

h3 {
  font-family: var(--font-sans);
  font-size: clamp(1.15rem, 2vw, 1.48rem);
  font-weight: 700;
  line-height: 1.38;
  letter-spacing: -0.01em;
  color: var(--color-indigo);
}

h4 {
  font-family: var(--font-sans);
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.45;
  color: var(--color-indigo);
}

p {
  margin-bottom: 1em;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

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

img {
  height: auto;
}

a {
  color: var(--color-cyan);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  transition: color 220ms var(--ease), border-color 220ms var(--ease), background-color 220ms var(--ease);
}

a:hover {
  color: var(--color-orange);
}

button {
  color: inherit;
}

::selection {
  color: var(--color-snow);
  background: var(--color-cyan);
}

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 3px solid var(--color-orange);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 50%;
  z-index: 220;
  padding: 11px 18px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-pill);
  color: var(--color-snow);
  background: var(--color-ink);
  box-shadow: 0 12px 30px rgba(7, 25, 35, 0.24);
  font-size: 0.88rem;
  font-weight: 700;
  text-decoration: none;
  pointer-events: auto;
  transform: translate(-50%, -160%);
  transition: transform 220ms var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  color: var(--color-snow);
  transform: translate(-50%, 0);
}

.container {
  width: min(calc(100% - var(--gutter) - var(--gutter)), var(--layout-max));
  margin-inline: auto;
}

.page-shell {
  padding-block: clamp(2.5rem, 6vw, 6rem);
}

.section {
  margin-block-start: clamp(2.5rem, 6vw, 6rem);
}

.section-head {
  display: grid;
  gap: 12px;
  max-width: 760px;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.kicker,
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  color: var(--color-gold);
  font-family: var(--font-numeric);
  font-size: 0.74rem;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.kicker::before,
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--color-gold);
}

.display-title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: clamp(2.8rem, 7vw, 6rem);
  font-weight: 700;
  line-height: 1.02;
  letter-spacing: -0.015em;
  color: var(--color-indigo);
  text-wrap: balance;
}

.section-title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: clamp(1.8rem, 3.8vw, 3.2rem);
  font-weight: 700;
  line-height: 1.14;
  color: var(--color-indigo);
  text-wrap: balance;
}

.lede {
  max-width: 62ch;
  margin: 0;
  color: rgba(7, 25, 35, 0.72);
  font-size: clamp(1.04rem, 1.35vw, 1.28rem);
  line-height: 1.82;
}

.body-copy {
  color: rgba(7, 25, 35, 0.82);
  font-size: 1rem;
  line-height: 1.75;
}

.muted {
  color: rgba(7, 25, 35, 0.58);
}

.content-column {
  max-width: 68ch;
}

.rule {
  height: 1px;
  margin-block: clamp(24px, 4vw, 40px);
  border: 0;
  background: linear-gradient(90deg, rgba(201, 154, 61, 0.65), rgba(16, 42, 67, 0.12), transparent);
}

.grid {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
}

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

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

.grid--4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.grid--split {
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  align-items: start;
}

.action-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 12px;
  margin-top: clamp(20px, 3vw, 32px);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: 0.92rem;
  font-weight: 700;
  line-height: 1;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  transition:
    transform 240ms var(--ease),
    background-color 240ms var(--ease),
    border-color 240ms var(--ease),
    color 240ms var(--ease),
    box-shadow 240ms var(--ease);
}

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

.button--primary {
  color: var(--color-ink);
  background: var(--color-orange);
  box-shadow: 0 12px 26px rgba(242, 138, 46, 0.22);
}

.button--primary:hover {
  color: var(--color-ink);
  background: #FF9F4D;
  box-shadow: 0 16px 30px rgba(242, 138, 46, 0.3);
}

.button--secondary {
  color: var(--color-snow);
  background: var(--color-cyan);
  box-shadow: 0 12px 26px rgba(11, 110, 138, 0.18);
}

.button--secondary:hover {
  color: var(--color-snow);
  background: #0D86A7;
}

.button--ghost {
  color: var(--color-indigo);
  border-color: rgba(16, 42, 67, 0.2);
  background: rgba(247, 250, 252, 0.72);
}

.button--ghost:hover {
  color: var(--color-cyan);
  border-color: rgba(11, 110, 138, 0.4);
  background: rgba(11, 110, 138, 0.06);
}

.button--small {
  min-height: 38px;
  padding-inline: 15px;
  font-size: 0.82rem;
}

.breadcrumb {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
}

.breadcrumb-item {
  display: inline-flex;
  align-items: center;
  color: rgba(7, 25, 35, 0.58);
  font-size: 0.82rem;
}

.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-inline: 10px;
  color: var(--color-gold);
}

.breadcrumb-link {
  color: rgba(7, 25, 35, 0.66);
  text-decoration: none;
}

.breadcrumb-link:hover {
  color: var(--color-cyan);
}

.breadcrumb-link[aria-current="page"] {
  color: var(--color-indigo);
  font-weight: 700;
  pointer-events: none;
}

.card {
  position: relative;
  padding: clamp(20px, 3vw, 30px);
  border: var(--hairline);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.84);
  box-shadow: var(--shadow-card);
}

.card--tinted {
  background: linear-gradient(155deg, rgba(221, 232, 236, 0.86), rgba(247, 250, 252, 0.96));
}

.card__index {
  display: block;
  margin-bottom: 14px;
  color: var(--color-gold);
  font-family: var(--font-numeric);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.card__title {
  margin: 0 0 0.55em;
  font-family: var(--font-sans);
  font-size: 1.12rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-indigo);
}

.card__meta {
  margin: 0 0 12px;
  color: var(--color-cyan);
  font-family: var(--font-numeric);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
}

.card__text {
  margin: 0;
  color: rgba(7, 25, 35, 0.7);
  font-size: 0.92rem;
  line-height: 1.72;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  padding: 3px 10px;
  border: 1px solid rgba(11, 110, 138, 0.2);
  border-radius: var(--radius-pill);
  color: var(--color-cyan);
  background: rgba(11, 110, 138, 0.06);
  font-size: 0.74rem;
  font-weight: 600;
  line-height: 1.4;
}

.tag--orange {
  color: #7A3700;
  border-color: rgba(242, 138, 46, 0.28);
  background: rgba(242, 138, 46, 0.12);
}

.tag--teal {
  color: #0D655D;
  border-color: rgba(43, 168, 154, 0.28);
  background: rgba(43, 168, 154, 0.12);
}

.chapter-nav {
  position: sticky;
  top: 118px;
  padding: 18px;
  border: var(--hairline);
  border-radius: var(--radius-md);
  background: rgba(247, 250, 252, 0.9);
  box-shadow: 0 12px 30px rgba(7, 25, 35, 0.05);
  backdrop-filter: blur(14px);
}

.chapter-nav-title {
  margin: 0 0 12px;
  color: var(--color-gold);
  font-family: var(--font-numeric);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.chapter-nav-list {
  display: grid;
  gap: 3px;
}

.chapter-link {
  display: block;
  padding: 8px 10px;
  border-left: 2px solid rgba(16, 42, 67, 0.12);
  color: rgba(7, 25, 35, 0.66);
  font-size: 0.86rem;
  line-height: 1.5;
  text-decoration: none;
}

.chapter-link:hover {
  border-left-color: var(--color-cyan);
  color: var(--color-cyan);
  background: rgba(11, 110, 138, 0.05);
}

.chapter-link[aria-current="location"] {
  border-left-color: var(--color-orange);
  color: var(--color-indigo);
  background: rgba(242, 138, 46, 0.08);
  font-weight: 700;
}

.step-list {
  display: grid;
  gap: 0;
}

.step {
  position: relative;
  padding: 0 0 26px 46px;
  border-left: 1px solid rgba(16, 42, 67, 0.16);
}

.step:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.step__index {
  position: absolute;
  top: 0;
  left: -17px;
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border: 1px solid rgba(201, 154, 61, 0.6);
  border-radius: 50%;
  color: var(--color-gold);
  background: var(--color-snow);
  font-family: var(--font-numeric);
  font-size: 0.78rem;
  font-weight: 700;
}

.step[data-current="true"] .step__index {
  color: var(--color-ink);
  border-color: var(--color-orange);
  background: var(--color-orange);
  animation: step-pulse 1.8s ease-out infinite;
}

.step__title {
  margin: 0 0 6px;
  color: var(--color-indigo);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.5;
}

.step__text {
  margin: 0;
  color: rgba(7, 25, 35, 0.68);
  font-size: 0.9rem;
  line-height: 1.7;
}

@keyframes step-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(242, 138, 46, 0.3);
  }
  70% {
    box-shadow: 0 0 0 10px rgba(242, 138, 46, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(242, 138, 46, 0);
  }
}

.media-frame {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  aspect-ratio: 16 / 10;
  border: 1px solid rgba(16, 42, 67, 0.12);
  border-radius: var(--radius-lg);
  background: var(--color-mist);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.36), var(--shadow-card);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide {
  aspect-ratio: 21 / 9;
}

.media-frame--portrait {
  aspect-ratio: 4 / 5;
}

.media-frame--square {
  aspect-ratio: 1 / 1;
}

.media-frame--map {
  background-image:
    repeating-radial-gradient(ellipse at 72% 42%, transparent 0 28px, rgba(11, 110, 138, 0.22) 29px 30px, transparent 31px 59px),
    linear-gradient(145deg, rgba(221, 232, 236, 0.95), rgba(247, 250, 252, 0.95));
}

.media-frame--diagram {
  background-image:
    linear-gradient(rgba(11, 110, 138, 0.11) 1px, transparent 1px),
    linear-gradient(90deg, rgba(11, 110, 138, 0.11) 1px, transparent 1px),
    linear-gradient(145deg, rgba(243, 228, 200, 0.56), rgba(247, 250, 252, 0.9));
  background-size: 28px 28px, 28px 28px, auto;
}

.media-frame__label {
  position: absolute;
  top: 16px;
  left: 16px;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 3px 10px;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-pill);
  color: var(--color-snow);
  background: rgba(7, 25, 35, 0.64);
  font-family: var(--font-numeric);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  backdrop-filter: blur(8px);
}

.media-caption {
  margin-top: 10px;
  color: rgba(7, 25, 35, 0.56);
  font-size: 0.8rem;
  line-height: 1.6;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 14px var(--gutter) 0;
  pointer-events: none;
}

.header-island {
  display: flex;
  width: min(calc(100% - var(--gutter) - var(--gutter)), var(--layout-max));
  min-height: 66px;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-inline: auto;
  padding: 9px 11px 9px 18px;
  border: 1px solid rgba(16, 42, 67, 0.14);
  border-radius: var(--radius-pill);
  background: rgba(247, 250, 252, 0.92);
  box-shadow: var(--shadow-island);
  backdrop-filter: blur(18px);
  pointer-events: auto;
  transition: background-color 240ms var(--ease), box-shadow 240ms var(--ease);
}

.site-header[data-scrolled="true"] .header-island {
  background: rgba(255, 255, 255, 0.97);
  box-shadow: 0 20px 60px rgba(7, 25, 35, 0.16), inset 0 1px 0 rgba(255, 255, 255, 0.86);
}

.brand-mark {
  display: inline-flex;
  min-width: 0;
  align-items: center;
  gap: 12px;
  color: var(--color-indigo);
  text-decoration: none;
}

.brand-mark:hover {
  color: var(--color-indigo);
}

.brand-sigil {
  position: relative;
  display: block;
  flex: 0 0 auto;
  width: 42px;
  height: 42px;
  overflow: hidden;
  border: 1px solid rgba(16, 42, 67, 0.12);
  border-radius: 50%;
  background:
    radial-gradient(circle at 34% 30%, rgba(255, 255, 255, 0.95) 0 4px, transparent 5px),
    conic-gradient(from 210deg, var(--color-cyan), var(--color-teal), var(--color-orange), var(--color-cyan));
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.24);
  transition: transform 240ms var(--ease);
}

.brand-mark:hover .brand-sigil {
  transform: rotate(-8deg) scale(1.03);
}

.brand-sigil::before {
  content: "";
  position: absolute;
  inset: 8px;
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: 50%;
}

.brand-sigil::after {
  content: "";
  position: absolute;
  top: 7px;
  right: 9px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-orange);
  box-shadow: 0 0 0 3px rgba(242, 138, 46, 0.22);
}

.brand-copy {
  display: grid;
  min-width: 0;
  gap: 1px;
}

.brand-name {
  display: block;
  font-family: var(--font-heading);
  font-size: 1.24rem;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.01em;
}

.brand-descriptor {
  display: block;
  overflow: hidden;
  color: rgba(16, 42, 67, 0.6);
  font-size: 0.7rem;
  font-weight: 500;
  line-height: 1.45;
  white-space: nowrap;
  text-overflow: ellipsis;
}

.header-tools {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 8px;
}

.header-cta {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding: 0 16px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  transition:
    transform 240ms var(--ease),
    background-color 240ms var(--ease),
    border-color 240ms var(--ease),
    color 240ms var(--ease);
}

.header-cta:hover {
  transform: translateY(-1px);
}

.header-cta--ghost {
  color: var(--color-indigo);
  border-color: rgba(16, 42, 67, 0.18);
  background: rgba(255, 255, 255, 0.48);
}

.header-cta--ghost:hover {
  color: var(--color-cyan);
  border-color: rgba(11, 110, 138, 0.34);
  background: rgba(11, 110, 138, 0.06);
}

.header-cta--solid {
  color: var(--color-ink);
  background: var(--color-orange);
  box-shadow: 0 8px 20px rgba(242, 138, 46, 0.2);
}

.header-cta--solid:hover {
  color: var(--color-ink);
  background: #FF9F4D;
}

.nav-toggle {
  display: none;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 12px;
  border: 1px solid rgba(16, 42, 67, 0.16);
  border-radius: var(--radius-pill);
  color: var(--color-indigo);
  background: rgba(11, 110, 138, 0.07);
  font-size: 0.8rem;
  font-weight: 700;
  line-height: 1;
  cursor: pointer;
  transition: background-color 220ms var(--ease), color 220ms var(--ease), border-color 220ms var(--ease);
}

.nav-toggle:hover {
  border-color: rgba(11, 110, 138, 0.32);
  background: rgba(11, 110, 138, 0.12);
}

.nav-toggle[aria-expanded="true"] {
  color: var(--color-snow);
  border-color: rgba(63, 208, 201, 0.32);
  background: var(--color-indigo);
}

.nav-toggle-lines {
  display: grid;
  width: 18px;
  gap: 4px;
}

.nav-toggle-lines span {
  display: block;
  width: 18px;
  height: 1.5px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 220ms var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-lines span:first-child {
  transform: translateY(2.75px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-lines span:last-child {
  transform: translateY(-2.75px) rotate(-45deg);
}

.nav-toggle-label {
  display: inline-block;
  line-height: 1;
}

.site-nav {
  width: min(calc(100% - var(--gutter) - var(--gutter)), var(--layout-max));
  margin: 8px auto 0;
  pointer-events: auto;
}

.site-nav-inner {
  display: flex;
  align-items: center;
  gap: clamp(10px, 2vw, 24px);
  padding: 6px 8px 6px 18px;
  border: 1px solid rgba(63, 208, 201, 0.22);
  border-radius: var(--radius-pill);
  background: rgba(16, 42, 67, 0.96);
  box-shadow: 0 14px 36px rgba(7, 25, 35, 0.18);
  backdrop-filter: blur(14px);
}

.nav-kicker {
  flex: 0 0 auto;
  margin: 0;
  color: var(--color-gold);
  font-family: var(--font-numeric);
  font-size: 0.66rem;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 0.14em;
  white-space: nowrap;
}

.nav-list {
  display: flex;
  flex: 1 1 auto;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: 2px;
}

.nav-link {
  display: inline-flex;
  min-height: 38px;
  align-items: center;
  padding: 0 12px;
  border-radius: var(--radius-pill);
  color: #E6F1F3;
  font-size: 0.83rem;
  font-weight: 500;
  line-height: 1.2;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 220ms var(--ease), color 220ms var(--ease), transform 220ms var(--ease);
}

.nav-link:hover {
  color: #FFFFFF;
  background: rgba(63, 208, 201, 0.14);
  transform: translateY(-1px);
}

.site-nav .nav-link[aria-current="page"] {
  color: var(--color-ink);
  background: var(--color-electric);
  font-weight: 700;
  box-shadow: 0 0 0 1px rgba(63, 208, 201, 0.45), 0 0 24px rgba(63, 208, 201, 0.18);
}

.site-nav .nav-link[aria-current="page"]:hover {
  color: var(--color-ink);
  background: var(--color-electric);
}

.site-footer {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  margin-top: clamp(64px, 9vw, 130px);
  color: var(--color-snow);
  background:
    radial-gradient(ellipse at 12% 0%, rgba(63, 208, 201, 0.18), transparent 42%),
    linear-gradient(145deg, #071923 0%, #102A43 54%, #0B3A4A 100%);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: -28% -10%;
  z-index: -1;
  background: repeating-radial-gradient(ellipse at 82% 30%, transparent 0 34px, rgba(63, 208, 201, 0.1) 35px 36px, transparent 37px 68px);
  opacity: 0.9;
  pointer-events: none;
}

.footer-inner {
  position: relative;
  z-index: 1;
  width: min(calc(100% - var(--gutter) - var(--gutter)), var(--layout-max));
  margin-inline: auto;
  padding-block: clamp(48px, 7vw, 92px) 26px;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.35fr);
  gap: clamp(34px, 6vw, 82px);
  align-items: start;
}

.footer-brand-link {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: var(--color-snow);
  text-decoration: none;
}

.footer-brand-link:hover {
  color: var(--color-snow);
}

.footer-monogram {
  display: grid;
  flex: 0 0 auto;
  width: 58px;
  height: 58px;
  place-items: center;
  border: 1px solid rgba(201, 154, 61, 0.66);
  border-radius: 50%;
  color: var(--color-gold);
  background: rgba(201, 154, 61, 0.06);
  font-family: var(--font-numeric);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  transition: color 220ms var(--ease), border-color 220ms var(--ease), background-color 220ms var(--ease);
}

.footer-brand-link:hover .footer-monogram {
  color: var(--color-ink);
  border-color: var(--color-orange);
  background: var(--color-orange);
}

.footer-brand-copy {
  display: grid;
  gap: 3px;
}

.footer-brand-name {
  display: block;
  font-family: var(--font-heading);
  font-size: 1.26rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-snow);
}

.footer-brand-line {
  display: block;
  color: rgba(221, 232, 236, 0.7);
  font-size: 0.76rem;
  line-height: 1.5;
}

.footer-signature {
  max-width: 18em;
  margin: 28px 0 20px;
  color: var(--color-snow);
  font-family: var(--font-heading);
  font-size: clamp(1.45rem, 2.4vw, 2rem);
  font-weight: 700;
  line-height: 1.5;
  letter-spacing: 0.01em;
}

.footer-coordinate {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  margin: 0;
  color: var(--color-gold);
  font-family: var(--font-numeric);
  font-size: 0.7rem;
  font-weight: 600;
  line-height: 1.6;
  letter-spacing: 0.08em;
}

.footer-coordinate-item {
  display: inline-flex;
  align-items: center;
}

.footer-coordinate-item + .footer-coordinate-item::before {
  content: "";
  width: 18px;
  height: 1px;
  margin-right: 14px;
  background: rgba(201, 154, 61, 0.54);
}

.footer-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(22px, 4vw, 48px);
}

.footer-col {
  min-width: 0;
}

.footer-col-title {
  margin: 0 0 17px;
  color: var(--color-gold);
  font-family: var(--font-sans);
  font-size: 0.76rem;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 0.12em;
}

.footer-list {
  display: grid;
  gap: 9px;
}

.footer-link {
  display: inline-block;
  color: rgba(221, 232, 236, 0.82);
  font-size: 0.9rem;
  line-height: 1.55;
  text-decoration: none;
  transition: color 220ms var(--ease);
}

.footer-link::before {
  content: "";
  display: inline-block;
  width: 0;
  height: 1px;
  margin-right: 0;
  vertical-align: middle;
  background: var(--color-orange);
  transition: width 220ms var(--ease), margin 220ms var(--ease);
}

.footer-link:hover,
.footer-link:focus-visible {
  color: #FFFFFF;
}

.footer-link:hover::before,
.footer-link:focus-visible::before {
  width: 14px;
  margin-right: 8px;
}

.footer-contact-panel {
  display: grid;
  grid-template-columns: minmax(0, 0.75fr) minmax(0, 1.5fr) minmax(0, 1.15fr);
  gap: clamp(22px, 4vw, 42px);
  align-items: start;
  margin-top: clamp(34px, 5vw, 58px);
  padding-block: 24px;
  border-top: 1px solid rgba(221, 232, 236, 0.14);
  border-bottom: 1px solid rgba(221, 232, 236, 0.14);
}

.footer-contact-heading {
  min-width: 0;
}

.footer-contact-label {
  margin: 0 0 7px;
  color: var(--color-electric);
  font-family: var(--font-numeric);
  font-size: 0.68rem;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 0.14em;
}

.footer-contact-title {
  margin: 0;
  color: var(--color-snow);
  font-family: var(--font-heading);
  font-size: 1.14rem;
  font-weight: 700;
  line-height: 1.35;
}

.footer-contact-body {
  display: grid;
  gap: 8px;
  min-width: 0;
}

.footer-contact-line {
  display: flex;
  flex-wrap: wrap;
  gap: 5px 10px;
  margin: 0;
  color: rgba(221, 232, 236, 0.8);
  font-size: 0.84rem;
  line-height: 1.65;
}

.footer-contact-key {
  flex: 0 0 4.6em;
  color: var(--color-gold);
  font-weight: 600;
}

.footer-contact-value {
  min-width: 0;
  color: rgba(247, 250, 252, 0.94);
  overflow-wrap: anywhere;
}

.footer-note {
  margin: 0;
  color: rgba(221, 232, 236, 0.6);
  font-size: 0.76rem;
  line-height: 1.7;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px 24px;
  padding-top: 20px;
}

.footer-legal {
  margin: 0;
  color: rgba(221, 232, 236, 0.56);
  font-family: var(--font-numeric);
  font-size: 0.72rem;
  line-height: 1.7;
  letter-spacing: 0.03em;
}

.footer-mini-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 16px;
}

.footer-mini-link {
  color: rgba(221, 232, 236, 0.74);
  font-size: 0.76rem;
  line-height: 1.6;
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.footer-mini-link:hover {
  color: var(--color-electric);
  border-bottom-color: rgba(63, 208, 201, 0.7);
}

.reading-progress {
  position: fixed;
  inset: 0 0 auto;
  z-index: 160;
  height: 3px;
  overflow: hidden;
  pointer-events: none;
}

.reading-progress-fill {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--color-cyan), var(--color-electric) 55%, var(--color-orange));
  transform: scaleX(0);
  transform-origin: 0 50%;
}

.to-top {
  position: fixed;
  right: clamp(16px, 3vw, 32px);
  bottom: clamp(16px, 3vw, 32px);
  z-index: 95;
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border: 1px solid rgba(16, 42, 67, 0.18);
  border-radius: 50%;
  color: var(--color-indigo);
  background: rgba(247, 250, 252, 0.9);
  box-shadow: 0 12px 30px rgba(7, 25, 35, 0.14);
  opacity: 0;
  visibility: hidden;
  cursor: pointer;
  transform: translateY(10px);
  backdrop-filter: blur(12px);
  transition:
    opacity 220ms var(--ease),
    visibility 220ms var(--ease),
    transform 220ms var(--ease),
    background-color 220ms var(--ease),
    color 220ms var(--ease),
    border-color 220ms var(--ease);
}

.to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.to-top:hover {
  color: var(--color-ink);
  border-color: var(--color-orange);
  background: var(--color-orange);
}

.to-top-arrow {
  font-family: var(--font-numeric);
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1;
}

@media (max-width: 1000px) {
  .grid--4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .grid--3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 960px) {
  html {
    scroll-padding-top: 100px;
  }

  .site-header {
    padding: 10px var(--gutter) 0;
  }

  .header-island {
    min-height: 60px;
    padding: 8px 8px 8px 12px;
    border-radius: 24px;
  }

  .brand-sigil {
    width: 38px;
    height: 38px;
  }

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

  .brand-descriptor {
    font-size: 0.66rem;
  }

  .header-cta--ghost {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    max-height: 0;
    margin-top: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transition:
      max-height 280ms var(--ease),
      opacity 220ms var(--ease),
      visibility 0s linear 280ms,
      margin-top 220ms var(--ease);
  }

  .site-nav[data-open="true"] {
    max-height: 80vh;
    margin-top: 10px;
    overflow-y: auto;
    opacity: 1;
    visibility: visible;
    transition:
      max-height 340ms var(--ease),
      opacity 240ms var(--ease),
      margin-top 240ms var(--ease);
  }

  .site-nav-inner {
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding: 16px;
    border-radius: 24px;
  }

  .nav-kicker {
    padding-left: 2px;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 4px;
  }

  .nav-link {
    min-height: 42px;
    justify-content: flex-start;
    padding: 10px 14px;
    border-radius: 12px;
    font-size: 0.94rem;
  }

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

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

  .footer-contact-panel {
    grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.4fr);
  }

  .footer-note {
    grid-column: 1 / -1;
  }

  .chapter-nav {
    position: static;
  }
}

@media (max-width: 820px) {
  .grid--split,
  .grid--2 {
    grid-template-columns: 1fr;
  }

  .footer-columns {
    gap: 24px;
  }
}

@media (max-width: 720px) {
  .header-cta--solid {
    display: none;
  }

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

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

  .footer-note {
    grid-column: auto;
  }

  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
  }

  .grid--3 {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .brand-descriptor {
    display: none;
  }

  .brand-name {
    font-size: 1.04rem;
  }

  .brand-sigil {
    width: 34px;
    height: 34px;
  }

  .header-island {
    gap: 10px;
  }

  .nav-toggle {
    padding-inline: 10px;
    font-size: 0.76rem;
  }

  .footer-columns {
    grid-template-columns: 1fr;
    gap: 22px;
  }

  .footer-signature {
    font-size: 1.36rem;
  }

  .footer-coordinate {
    align-items: flex-start;
    flex-direction: column;
    gap: 6px;
  }

  .footer-coordinate-item + .footer-coordinate-item::before {
    display: none;
  }

  .to-top {
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 420px) {
  .display-title {
    font-size: clamp(2.35rem, 12vw, 3.25rem);
  }

  .footer-contact-key {
    flex-basis: 100%;
  }

  .footer-mini-nav {
    gap: 6px 12px;
  }
}

@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;
    scroll-behavior: auto !important;
  }

  .step[data-current="true"] .step__index {
    animation: none;
  }
}