:root {
  --paper: #F4EBD9;
  --cream: #FBF6ED;
  --ink: #2B2118;
  --line: #B8A98E;
  --ocean: #1D3557;
  --stage: #102A43;
  --ember: #E4572E;
  --gold: #C9A227;
  --font-head: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --font-body: "Noto Serif SC", "Songti SC", "SimSun", "Iowan Old Style", Georgia, serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --rail-width: 272px;
}

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

* {
  margin: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background-color: var(--paper);
  -webkit-font-smoothing: antialiased;
  padding-left: 0;
}

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

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

h1,
h2,
h3,
h4 {
  font-family: var(--font-head);
  font-weight: 300;
  line-height: 1.2;
}

a {
  color: var(--ocean);
}

:focus-visible {
  outline: 3px solid var(--ember);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

.skip-chip {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 200;
  padding: 0.5rem 1rem;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-head);
  font-size: 0.875rem;
  text-decoration: none;
  border: 2px solid var(--ember);
  border-radius: 2px;
  transform: translateY(-200%);
  transition: transform 0.2s;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--rail-width);
  background-color: var(--ocean);
  background-image:
    linear-gradient(rgba(244, 235, 217, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(244, 235, 217, 0.05) 1px, transparent 1px);
  background-size: 34px 34px;
  border-right: 1px solid rgba(201, 162, 39, 0.35);
  display: flex;
  flex-direction: column;
  z-index: 105;
}

.site-header__main {
  flex-shrink: 0;
  padding: 1.5rem 1.25rem 0.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-mark {
  display: inline-flex;
  flex-direction: column;
  text-decoration: none;
  border-bottom: 2px solid var(--gold);
  padding-bottom: 0.75rem;
}

.brand-mark__cn {
  font-family: var(--font-head);
  font-size: 1.875rem;
  font-weight: 700;
  color: var(--paper);
  letter-spacing: 0.06em;
  line-height: 1;
}

.brand-mark__en {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: rgba(244, 235, 217, 0.6);
  margin-top: 0.375rem;
}

.nav-toggle {
  display: none;
}

.site-nav {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}

.site-nav__links {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
  flex: 1;
  justify-content: center;
  padding: 0.5rem 0.875rem;
}

.site-nav__link {
  display: flex;
  align-items: baseline;
  gap: 0.875rem;
  padding: 0.625rem 0.75rem;
  border-radius: 3px;
  text-decoration: none;
  color: rgba(244, 235, 217, 0.82);
  border-left: 3px solid transparent;
  transition: background 0.25s, color 0.25s, border-color 0.25s;
}

.site-nav__link:hover {
  background: rgba(244, 235, 217, 0.08);
  color: var(--cream);
}

.site-nav__link[aria-current="page"] {
  color: #fff;
  border-left-color: var(--ember);
  background: linear-gradient(90deg, rgba(228, 87, 46, 0.2) 0%, rgba(228, 87, 46, 0.04) 100%);
}

.site-nav__num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--gold);
  letter-spacing: 0.05em;
}

.site-nav__label {
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.02em;
}

.cta-stamp {
  display: block;
  flex-shrink: 0;
  background: var(--ember);
  color: var(--cream);
  text-align: left;
  padding: 0.875rem 1rem;
  border-radius: 3px;
  border: 1px solid rgba(43, 33, 24, 0.15);
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.18);
  text-decoration: none;
  margin: 0.75rem 1.25rem 0.25rem;
  transition: background 0.25s, transform 0.15s, box-shadow 0.25s;
}

.cta-stamp:hover {
  background: #c3421e;
  transform: translateY(-2px);
  box-shadow: 4px 6px 0 rgba(0, 0, 0, 0.18);
}

.cta-stamp__text {
  display: block;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: 0.02em;
}

.cta-stamp__tag {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: rgba(251, 246, 237, 0.75);
  margin-top: 0.25rem;
  letter-spacing: 0.08em;
}

.rail-meta {
  flex-shrink: 0;
  padding: 0.75rem 1.25rem 1.25rem;
}

.rail-progress {
  height: 6px;
  background: rgba(244, 235, 217, 0.15);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.rail-progress__fill {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--gold), var(--ember));
  transition: width 0.15s ease-out;
}

.rail-meta__coords {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: rgba(244, 235, 217, 0.5);
}

.main-content {
  min-height: 70vh;
}

.page-shell {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: clamp(2rem, 6vw, 4.5rem) clamp(1.25rem, 5vw, 3.5rem);
}

.paper-card {
  position: relative;
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 2px;
  box-shadow: 6px 8px 0 rgba(43, 33, 24, 0.07), 0 1px 3px rgba(43, 33, 24, 0.08);
  padding: clamp(1.5rem, 3vw, 2.5rem);
}

.paper-stack {
  position: relative;
}

.paper-stack > .paper-card {
  position: relative;
  z-index: 1;
}

.paper-stack::before,
.paper-stack::after {
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  background: var(--cream);
  border: 1px solid var(--line);
  border-radius: 2px;
}

.paper-stack::before {
  top: 10px;
  left: 8px;
}

.paper-stack::after {
  top: 18px;
  left: 16px;
  background: var(--paper);
  opacity: 0.7;
}

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ember);
  border-bottom: 1px solid var(--gold);
  padding-bottom: 0.5rem;
  margin-bottom: 1.25rem;
}

.section-title {
  font-family: var(--font-head);
  font-weight: 300;
  font-size: clamp(2rem, 5vw, 3.75rem);
  line-height: 1.12;
  color: var(--ink);
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
}

.lead {
  font-family: var(--font-body);
  font-size: 1.125rem;
  line-height: 1.8;
  color: rgba(43, 33, 24, 0.85);
  max-width: 62ch;
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  padding: 0.875rem 1.75rem;
  border-radius: 999px;
  border: 1px solid var(--ocean);
  background: transparent;
  color: var(--ocean);
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.25s, color 0.25s, transform 0.15s;
}

.btn:hover {
  background: var(--ocean);
  color: var(--cream);
}

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

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

.btn--primary:hover {
  background: #c3421e;
  border-color: #c3421e;
  color: #fff;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  padding: 0.375rem 0.875rem;
  border: 1px solid var(--gold);
  border-radius: 2px;
  color: var(--ocean);
  background: var(--cream);
  text-transform: uppercase;
}

.crumb {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  margin-bottom: 2rem;
}

.crumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
  list-style: none;
  padding: 0;
  margin: 0;
}

.crumb__item {
  display: inline-flex;
  align-items: center;
}

.crumb__link {
  color: var(--ocean);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}

.crumb__link:hover {
  border-bottom-color: var(--ocean);
}

.crumb__separator {
  color: var(--line);
  margin: 0 0.25rem;
}

.crumb__current {
  color: var(--ink);
  opacity: 0.72;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: clamp(1.25rem, 3vw, 2rem);
}

.grid__span-4 {
  grid-column: span 4;
}

.grid__span-5 {
  grid-column: span 5;
}

.grid__span-6 {
  grid-column: span 6;
}

.grid__span-7 {
  grid-column: span 7;
}

.grid__span-8 {
  grid-column: span 8;
}

.grid__span-12 {
  grid-column: 1 / -1;
}

.media-frame {
  position: relative;
  overflow: hidden;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 3px;
  aspect-ratio: 16 / 9;
}

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

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

.media-frame--landscape {
  aspect-ratio: 16 / 9;
}

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

.site-footer {
  position: relative;
  background-color: var(--stage);
  color: rgba(251, 246, 237, 0.8);
  background-image:
    linear-gradient(rgba(244, 235, 217, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(244, 235, 217, 0.045) 1px, transparent 1px);
  background-size: 44px 44px;
  padding: clamp(2.5rem, 6vw, 5rem) clamp(1.25rem, 4vw, 3rem) 2rem;
  overflow: hidden;
}

.site-footer__orbit {
  position: absolute;
  top: -70px;
  right: -70px;
  width: 240px;
  height: 240px;
  border-radius: 50%;
  border: 1px solid rgba(201, 162, 39, 0.2);
  pointer-events: none;
}

.site-footer__orbit::before {
  content: "";
  position: absolute;
  inset: 28px;
  border-radius: 50%;
  border: 1px solid rgba(201, 162, 39, 0.15);
}

.site-footer__orbit::after {
  content: "";
  position: absolute;
  inset: 56px;
  border-radius: 50%;
  border: 1px solid rgba(201, 162, 39, 0.1);
}

.site-footer__main {
  position: relative;
  max-width: 1080px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 1fr;
  gap: 2.5rem 3rem;
}

.site-footer__name {
  font-family: var(--font-head);
  font-size: 2.5rem;
  font-weight: 300;
  color: var(--paper);
  letter-spacing: 0.06em;
  line-height: 1;
  margin-bottom: 0.5rem;
}

.site-footer__slogan {
  font-family: var(--font-body);
  font-size: 1rem;
  color: rgba(251, 246, 237, 0.7);
  margin-bottom: 1rem;
}

.site-footer__trust {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: rgba(251, 246, 237, 0.55);
  letter-spacing: 0.05em;
  border-top: 1px solid rgba(201, 162, 39, 0.25);
  padding-top: 1rem;
}

.site-footer__label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1rem;
}

.site-footer__link {
  display: block;
  color: rgba(251, 246, 237, 0.75);
  text-decoration: none;
  font-family: var(--font-head);
  font-size: 0.9375rem;
  padding: 0.375rem 0;
  transition: color 0.2s, padding-left 0.2s;
}

.site-footer__link:hover {
  color: var(--paper);
  padding-left: 0.5rem;
}

.site-footer__contact {
  font-family: var(--font-mono);
}

.site-footer__email,
.site-footer__phone {
  margin: 0.25rem 0;
  font-size: 0.9375rem;
  color: rgba(251, 246, 237, 0.85);
}

.site-footer__address {
  font-family: var(--font-body);
  font-size: 0.875rem;
  margin-top: 0.75rem;
  color: rgba(251, 246, 237, 0.55);
  max-width: 30ch;
  line-height: 1.6;
}

.site-footer__bottom {
  position: relative;
  max-width: 1080px;
  margin: 3.5rem auto 0;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(201, 162, 39, 0.25);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem 2rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: rgba(251, 246, 237, 0.5);
}

.return-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 90;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--ocean);
  color: var(--paper);
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.3s, transform 0.3s, background 0.3s;
}

.return-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.return-top:hover {
  background: var(--ember);
  border-color: var(--ember);
}

.return-top__glyph {
  display: inline-block;
  font-family: var(--font-mono);
  line-height: 1;
}

[data-reveal] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

@media (max-width: 1023.98px) {
  body {
    padding-left: 0;
  }

  .site-header {
    position: sticky;
    top: 0;
    width: 100%;
    height: auto;
    bottom: auto;
    background-color: var(--ocean);
    background-image: none;
    border-right: none;
    border-bottom: 2px solid var(--gold);
  }

  .site-header__main {
    padding: 0.625rem 1rem;
  }

  .brand-mark {
    padding-bottom: 0.375rem;
  }

  .brand-mark__cn {
    font-size: 1.375rem;
  }

  .brand-mark__en {
    font-size: 0.625rem;
  }

  .nav-toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 6px;
    width: 44px;
    height: 44px;
    padding: 10px;
    background: transparent;
    border: 1px solid rgba(244, 235, 217, 0.25);
    border-radius: 6px;
    cursor: pointer;
  }

  .nav-toggle__line {
    display: block;
    height: 2px;
    width: 100%;
    background: var(--paper);
    border-radius: 1px;
    transition: transform 0.3s, opacity 0.3s;
  }

  .site-header:has(.site-nav[data-open]) .nav-toggle__line:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }

  .site-header:has(.site-nav[data-open]) .nav-toggle__line:nth-child(2) {
    opacity: 0;
  }

  .site-header:has(.site-nav[data-open]) .nav-toggle__line:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }

  body:has(.site-nav[data-open])::after {
    content: "";
    position: fixed;
    inset: 0;
    background: rgba(16, 42, 67, 0.55);
    z-index: 104;
    pointer-events: none;
  }

  .site-nav {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: min(84vw, 320px);
    background: var(--stage);
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    padding: 4.75rem 1.25rem 1.25rem;
    z-index: 106;
    overflow-y: auto;
    box-shadow: 0 0 60px rgba(0, 0, 0, 0.45);
  }

  .site-nav[data-open] {
    transform: translateX(0);
  }

  .site-nav__links {
    padding: 0;
    justify-content: flex-start;
    gap: 0.25rem;
  }

  .cta-stamp {
    margin: 1.5rem 0 0.5rem;
  }

  .rail-meta {
    padding: 0.75rem 0 0.25rem;
  }

  .site-footer__main {
    grid-template-columns: 1fr;
    gap: 2.25rem;
  }

  .site-footer__orbit {
    width: 160px;
    height: 160px;
    top: -40px;
    right: -40px;
  }

  .return-top {
    right: 1rem;
    bottom: 1rem;
    width: 44px;
    height: 44px;
  }
}

@media (min-width: 1024px) {
  body {
    padding-left: var(--rail-width);
  }
}

@media (max-width: 767px) {
  .grid__span-4,
  .grid__span-5,
  .grid__span-6,
  .grid__span-7,
  .grid__span-8,
  .grid__span-12 {
    grid-column: 1 / -1;
  }

  .page-shell {
    padding-top: 1.75rem;
    padding-bottom: 2.5rem;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.375rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .site-nav,
  .site-nav__link,
  .cta-stamp,
  .return-top,
  .btn,
  .site-footer__link,
  .skip-chip,
  .nav-toggle__line {
    transition: none;
  }
}