:root {
  --c-deep-space: #0B1D3A;
  --c-prairie: #3D9970;
  --c-accent: #FF6B35;
  --c-ink: #111111;
  --c-white: #FFFFFF;
  --c-light-gray: #E5E5E5;
  --c-mid-gray: #666666;
  --c-dark-gray: #2A2A2A;
  --font-sans: "Noto Sans SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --content-width: 1280px;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --radius: 0;
}

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

html {
  color-scheme: light;
  scroll-behavior: smooth;
  scroll-padding-top: 2rem;
}

body {
  margin: 0;
  background: var(--c-white);
  color: var(--c-ink);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 300;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 1rem;
  color: var(--c-deep-space);
  font-family: var(--font-sans);
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

p {
  margin: 0 0 1rem;
}

ul, ol, dl, dd, figure, blockquote {
  margin: 0;
  padding: 0;
}

ul, ol {
  list-style: none;
}

img, video, canvas, svg {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: var(--c-deep-space);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

a:hover {
  color: var(--c-accent);
}

button {
  font: inherit;
  cursor: pointer;
}

code, pre, kbd {
  font-family: var(--font-mono);
}

:focus-visible {
  outline: 3px solid var(--c-accent);
  outline-offset: 3px;
}

#main-content {
  outline: none;
}

.container,
.header-inner,
.footer-inner {
  width: 100%;
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: clamp(1.5rem, 5vw, 4rem);
}

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

.page-hero {
  position: relative;
  padding: clamp(4rem, 8vw, 7rem) 0 clamp(2.5rem, 5vw, 4rem);
  background: var(--c-deep-space);
  color: var(--c-white);
  overflow: hidden;
}

.page-hero::before {
  content: "";
  position: absolute;
  inset: auto 0 0 auto;
  width: 42%;
  height: 100%;
  background: linear-gradient(135deg, transparent 0%, rgba(61, 153, 112, 0.28) 100%);
  pointer-events: none;
}

.page-hero h1 {
  position: relative;
  color: var(--c-white);
  font-size: clamp(2.75rem, 6vw, 5.5rem);
  max-width: 12em;
}

.page-hero .kicker {
  color: var(--c-accent);
}

.page-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 2fr);
  gap: clamp(2rem, 4vw, 4rem);
}

.index-rail {
  align-self: start;
  position: sticky;
  top: 2rem;
}

.content-rail {
  min-width: 0;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  z-index: 1300;
  padding: 0.75rem 1.25rem;
  background: var(--c-accent);
  color: var(--c-ink);
  font-weight: 700;
  text-decoration: none;
}

.skip-link:focus {
  top: 1rem;
}

.site-header {
  position: relative;
  background: var(--c-deep-space);
  color: var(--c-white);
}

.header-inner {
  padding-top: 1.25rem;
}

.header-masthead {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: end;
  gap: clamp(1rem, 3vw, 2.5rem);
  padding-bottom: 1.1rem;
}

.header-edition {
  margin: 0;
  color: rgba(255, 255, 255, 0.62);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  line-height: 1.9;
  text-transform: uppercase;
}

.header-edition--left {
  justify-self: start;
  text-align: left;
}

.header-edition--right {
  justify-self: end;
  text-align: right;
}

.edition-line {
  display: block;
}

.edition-line--en {
  color: rgba(255, 255, 255, 0.4);
}

.edition-line--accent {
  color: var(--c-accent);
}

.site-brand {
  display: block;
  text-align: center;
  text-decoration: none;
}

.brand-kicker {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--c-prairie);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

.brand-name {
  display: block;
  color: var(--c-white);
  font-size: clamp(2.25rem, 5vw, 4rem);
  font-weight: 900;
  line-height: 1;
  letter-spacing: 0.06em;
}

.brand-desc {
  display: block;
  margin-top: 0.55rem;
  padding-top: 0.4rem;
  border-top: 1px solid rgba(255, 255, 255, 0.28);
  color: rgba(255, 255, 255, 0.62);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
}

.header-tools {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 1rem;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  border: 1px solid rgba(255, 255, 255, 0.42);
  background: transparent;
  color: var(--c-white);
  padding: 0.5rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  line-height: 1;
}

.nav-toggle:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
}

.nav-toggle__icon {
  position: relative;
  width: 20px;
  height: 2px;
  background: currentColor;
  display: inline-block;
}

.nav-toggle__icon::before,
.nav-toggle__icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  transition: transform 0.18s ease, top 0.18s ease;
}

.nav-toggle__icon::before {
  top: -6px;
}

.nav-toggle__icon::after {
  top: 6px;
}

.nav-toggle.is-active .nav-toggle__icon {
  background: transparent;
}

.nav-toggle.is-active .nav-toggle__icon::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle.is-active .nav-toggle__icon::after {
  top: 0;
  transform: rotate(-45deg);
}

.site-nav {
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.nav-list {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0 2px;
}

.nav-link {
  display: block;
  padding: 0.85rem 1.25rem;
  color: rgba(255, 255, 255, 0.78);
  font-weight: 500;
  font-size: 0.9375rem;
  text-decoration: none;
  border-bottom: 3px solid transparent;
  transition: color 0.18s ease, background-color 0.18s ease, border-color 0.18s ease;
}

.nav-link:hover {
  color: var(--c-white);
  background: rgba(255, 255, 255, 0.06);
}

.nav-link[aria-current="page"] {
  color: var(--c-white);
  border-bottom-color: var(--c-accent);
  background: rgba(255, 255, 255, 0.05);
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1200;
  width: 100%;
  height: 4px;
  background: var(--c-accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
  will-change: transform;
}

.site-footer {
  background: var(--c-ink);
  color: rgba(255, 255, 255, 0.72);
  border-top: 4px solid var(--c-accent);
}

.footer-inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: clamp(2rem, 5vw, 4rem);
  padding-top: 3.5rem;
  padding-bottom: 2rem;
}

.footer-brand .footer-brand-name {
  display: inline-block;
  margin-bottom: 0.5rem;
  color: var(--c-white);
  font-size: 2rem;
  font-weight: 900;
  letter-spacing: 0.06em;
  text-decoration: none;
}

.footer-slogan {
  max-width: 24em;
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.0625rem;
  line-height: 1.6;
}

.footer-trust {
  max-width: 34em;
  color: rgba(255, 255, 255, 0.52);
  font-size: 0.8125rem;
  margin-top: 1rem;
}

.footer-links {
  display: grid;
  align-content: start;
  gap: 0.55rem;
}

.footer-contact {
  display: grid;
  align-content: start;
  gap: 0.35rem;
  font-size: 0.875rem;
  line-height: 1.7;
}

.footer-col-title {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--c-white);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.footer-links a {
  width: fit-content;
  color: rgba(255, 255, 255, 0.75);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.footer-links a:hover {
  color: var(--c-accent);
  border-bottom-color: var(--c-accent);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  padding: 1.25rem clamp(1.5rem, 5vw, 4rem);
}

.footer-bottom p {
  max-width: var(--content-width);
  margin-inline: auto;
  margin-bottom: 0;
  color: rgba(255, 255, 255, 0.55);
  font-size: 0.8125rem;
  line-height: 1.7;
}

.kicker {
  display: inline-block;
  margin-bottom: 0.5rem;
  color: var(--c-prairie);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 2rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--c-deep-space);
}

.section-head h1,
.section-head h2,
.section-head h3,
.section-head h4 {
  margin: 0;
}

.section-head__index {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--c-accent);
  letter-spacing: 0.1em;
}

.card {
  padding: clamp(1.5rem, 2vw, 2.5rem);
  border: 1px solid var(--c-light-gray);
  border-top: 3px solid var(--c-deep-space);
  background: var(--c-white);
}

.card--accent {
  border-top-color: var(--c-accent);
}

.card--prairie {
  border-top-color: var(--c-prairie);
}

.card__title {
  margin-bottom: 0.5rem;
}

.card__meta {
  margin-bottom: 1rem;
  color: var(--c-mid-gray);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.tag {
  display: inline-block;
  padding: 0.25em 0.65em;
  border: 1px solid var(--c-deep-space);
  color: var(--c-deep-space);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: transparent;
}

.tag--accent {
  border-color: var(--c-accent);
  background: var(--c-accent);
  color: var(--c-ink);
}

.tag--prairie {
  border-color: var(--c-prairie);
  background: var(--c-prairie);
  color: var(--c-white);
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.8rem 1.3rem;
  border: 1px solid var(--c-deep-space);
  background: var(--c-deep-space);
  color: var(--c-white);
  font-weight: 600;
  font-size: 0.9375rem;
  text-decoration: none;
  line-height: 1.2;
  transition: background-color 0.18s ease, border-color 0.18s ease, color 0.18s ease, transform 0.18s ease;
}

.btn:hover {
  background: var(--c-accent);
  border-color: var(--c-accent);
  color: var(--c-ink);
}

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

.btn--accent {
  border-color: var(--c-accent);
  background: var(--c-accent);
  color: var(--c-ink);
}

.btn--accent:hover {
  background: var(--c-deep-space);
  border-color: var(--c-deep-space);
  color: var(--c-white);
}

.btn-outline {
  background: transparent;
  color: var(--c-deep-space);
}

.btn-outline:hover {
  background: var(--c-deep-space);
  border-color: var(--c-deep-space);
  color: var(--c-white);
}

.panel {
  border: 1px solid var(--c-light-gray);
  background: var(--c-white);
}

.panel summary {
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  font-weight: 600;
  color: var(--c-deep-space);
  cursor: pointer;
}

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

.panel[open] summary {
  border-bottom: 1px solid var(--c-light-gray);
}

.panel-body {
  padding: 1.25rem 1.5rem;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 2rem;
  color: var(--c-mid-gray);
  font-size: 0.875rem;
}

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

.breadcrumb a:hover {
  color: var(--c-accent);
}

.breadcrumb li + li::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--c-accent);
}

.quote {
  margin: 2.5rem 0;
  padding-left: 1.5rem;
  border-left: 4px solid var(--c-prairie);
  color: var(--c-deep-space);
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.5;
}

.quote-meta {
  display: block;
  margin-top: 0.5rem;
  color: var(--c-mid-gray);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 300;
}

.info-list {
  display: grid;
  grid-template-columns: minmax(7em, 1fr) 2fr;
  gap: 0.55rem 1rem;
  font-size: 0.9375rem;
}

.info-list dt {
  color: var(--c-mid-gray);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.info-list dd {
  color: var(--c-ink);
}

.index-nav {
  border-top: 1px solid var(--c-light-gray);
}

.index-nav li {
  border-bottom: 1px solid var(--c-light-gray);
}

.index-nav a {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 0.7rem 0;
  color: var(--c-deep-space);
  text-decoration: none;
  font-weight: 500;
}

.index-nav a:hover {
  color: var(--c-accent);
}

.index-nav a span {
  color: var(--c-mid-gray);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.img-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--c-light-gray);
  background-color: var(--c-deep-space);
  background-image:
    linear-gradient(45deg, rgba(255, 255, 255, 0.06) 25%, transparent 25%, transparent 75%, rgba(255, 255, 255, 0.06) 75%),
    linear-gradient(45deg, rgba(255, 255, 255, 0.06) 25%, transparent 25%, transparent 75%, rgba(255, 255, 255, 0.06) 75%);
  background-size: 32px 32px;
  background-position: 0 0, 16px 16px;
}

.img-frame::after {
  content: "影像占位 · 数字草原";
  position: absolute;
  right: 0;
  bottom: 0;
  padding: 0.3rem 0.6rem;
  background: rgba(0, 0, 0, 0.55);
  color: rgba(255, 255, 255, 0.85);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
}

.rule {
  border: 0;
  border-top: 1px solid var(--c-light-gray);
  margin: 2.5rem 0;
}

.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

@media (max-width: 900px) {
  .page-grid {
    grid-template-columns: 1fr;
  }

  .index-rail {
    position: static;
  }

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

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

@media (max-width: 767px) {
  .header-inner {
    padding-top: 0.75rem;
  }

  .header-masthead {
    grid-template-columns: 1fr auto;
    align-items: center;
    padding-bottom: 0.75rem;
  }

  .header-edition--left,
  .header-edition--right {
    display: none;
  }

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

  .site-brand {
    text-align: left;
  }

  .brand-name {
    font-size: clamp(1.75rem, 8vw, 2.75rem);
  }

  .site-nav {
    border-top: 0;
  }

  .nav-list {
    display: none;
  }

  .site-nav[data-open] .nav-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.16);
  }

  .nav-link {
    padding: 0.85rem 0.5rem;
    border-bottom: 0;
    border-left: 3px solid transparent;
  }

  .nav-link[aria-current="page"] {
    background: transparent;
    border-bottom: 0;
    border-left-color: var(--c-accent);
  }

  .footer-inner {
    grid-template-columns: 1fr;
    padding-top: 2.5rem;
  }

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

@media (max-width: 480px) {
  .header-masthead {
    gap: 0.75rem;
  }

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

  .footer-bottom p {
    font-size: 0.75rem;
  }
}

@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;
  }

  .js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
}