:root {
  color-scheme: dark;
  --color-bg: #0A0A08;
  --color-panel: #11110E;
  --color-panel-raised: #181814;
  --color-panel-soft: #20201B;
  --color-border: #30302A;
  --color-border-bright: #48483F;
  --color-accent: #7CF7FF;
  --color-accent-dark: #237D82;
  --color-text: #F4F4EF;
  --color-muted: #9A9A91;
  --color-subtle: #707069;
  --color-warn: #C5C5B9;
  --color-success: #7CF7FF;
  --color-error: #F4F4EF;
  --color-white: #FFFFFF;
  --color-black: #000000;
  --color-shadow: rgba(0, 0, 0, 0.52);
  --color-shadow-soft: rgba(0, 0, 0, 0.26);
  --color-accent-glow: rgba(124, 247, 255, 0.18);
  --color-accent-soft: rgba(124, 247, 255, 0.08);
  --color-accent-faint: rgba(124, 247, 255, 0.035);
  --color-grid: rgba(244, 244, 239, 0.025);
  --color-overlay: rgba(10, 10, 8, 0.86);
  --color-veil: rgba(0, 0, 0, 0.68);
  --color-flag-red: #D94452;
  --color-flag-blue: #3157A4;
  --color-flag-navy: #274478;
  --color-flag-white: #F4F4EF;
  --color-flag-black: #11110E;

  --font-display: "Inter", "Noto Sans SC", "Noto Sans JP", "Noto Sans KR", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "Noto Sans JP", "Noto Sans KR", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Consolas, monospace;

  --radius-xs: 4px;
  --radius-sm: 7px;
  --radius-md: 11px;
  --radius-lg: 16px;
  --radius-pill: 999px;

  --page-width: 1376px;
  --reading-width: 768px;
  --header-height: 78px;
  --hero-min-height: 822px;
  --gutter: clamp(16px, 4vw, 32px);
  --section-space: clamp(72px, 9vw, 132px);
  --display-size: clamp(52px, 5.2vw, 68px);
  --display-line: 1.1;
  --body-size: 17px;
  --small-size: 13px;
  --micro-size: 11px;
  --border-thin: 1px;
  --toc-top: 92px;

  --shadow-window: 0 32px 80px var(--color-shadow);
  --shadow-panel: 0 20px 50px var(--color-shadow-soft);
  --shadow-accent: 0 0 26px var(--color-accent-glow);
  --transition-fast: 180ms ease;
  --transition-slow: 520ms cubic-bezier(0.2, 0.75, 0.25, 1);
}

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

html {
  min-width: 0;
  background: var(--color-bg);
  scroll-behavior: smooth;
}

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 0;
  margin: 0;
  overflow-x: clip;
  background:
    linear-gradient(var(--color-grid) var(--border-thin), transparent var(--border-thin)),
    linear-gradient(90deg, var(--color-grid) var(--border-thin), transparent var(--border-thin)),
    var(--color-bg);
  background-size: 72px 72px;
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--body-size);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

main,
section,
article,
aside,
header,
footer,
nav,
div,
li {
  min-width: 0;
}

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

img,
svg {
  display: block;
}

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

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

button,
a,
summary {
  -webkit-tap-highlight-color: transparent;
}

button {
  border: 0;
}

p,
ul,
ol,
blockquote,
pre,
table {
  margin-top: 0;
}

p {
  margin-bottom: 1.25em;
}

ul,
ol {
  padding-left: 1.35em;
}

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

:not(pre) > code {
  padding: 0.12em 0.36em;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-xs);
  background: var(--color-panel-raised);
  color: var(--color-warn);
  font-size: 0.88em;
  overflow-wrap: anywhere;
  word-break: break-word;
}

pre {
  max-width: 100%;
  padding: 20px;
  overflow-x: auto;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  color: var(--color-warn);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  -webkit-overflow-scrolling: touch;
}

pre code {
  white-space: pre;
}

::selection {
  background: var(--color-accent-dark);
  color: var(--color-white);
}

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

[hidden] {
  display: none !important;
}

.wrap {
  width: 100%;
  max-width: calc(var(--page-width) + (var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.reading-wrap {
  width: 100%;
  max-width: calc(var(--reading-width) + (var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  position: relative;
  overflow-x: clip;
  padding-top: var(--section-space);
  padding-bottom: var(--section-space);
}

.section-compact {
  padding-top: clamp(48px, 6vw, 82px);
  padding-bottom: clamp(48px, 6vw, 82px);
}

.section-rule {
  border-top: var(--border-thin) solid var(--color-border);
}

.stack > * + * {
  margin-top: 24px;
}

.cluster {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.grid {
  display: grid;
  gap: 20px;
}

.grid > * {
  min-width: 0;
}

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

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

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

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  text-wrap: balance;
}

h1,
.hero-title {
  max-width: 760px;
  margin-bottom: 0;
  font-size: var(--display-size);
  font-weight: 560;
  letter-spacing: -0.02em;
  line-height: var(--display-line);
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(34px, 4vw, 52px);
  font-weight: 560;
  letter-spacing: -0.02em;
  line-height: 1.14;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 590;
  line-height: 1.25;
}

h4 {
  margin-bottom: 10px;
  font-size: 18px;
  font-weight: 620;
  line-height: 1.35;
}

.title-nowrap {
  white-space: nowrap;
}

.title-accent {
  color: var(--color-accent);
  text-shadow: 0 0 34px var(--color-accent-glow);
}

.eyebrow {
  width: max-content;
  max-width: 100%;
  margin: 0 0 22px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px 8px 9px;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-warn);
  font-family: var(--font-mono);
  font-size: var(--micro-size);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.eyebrow-signal {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  border: var(--border-thin) solid var(--color-accent-dark);
  border-radius: 50%;
  color: var(--color-accent);
  font-size: 9px;
  box-shadow: inset 0 0 10px var(--color-accent-soft);
}

.lead {
  max-width: 720px;
  color: var(--color-muted);
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.65;
}

.muted {
  color: var(--color-muted);
}

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

.section-heading {
  max-width: 820px;
  margin-bottom: 46px;
}

.section-heading p {
  max-width: 680px;
  margin-bottom: 0;
  color: var(--color-muted);
}

.button,
.cta {
  min-height: 48px;
  padding: 0 22px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-text);
  font-size: 15px;
  font-weight: 650;
  line-height: 1;
  text-align: center;
  cursor: pointer;
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast),
    background var(--transition-fast),
    color var(--transition-fast);
}

.button:hover,
.cta:hover {
  transform: translateY(-2px);
}

.button-primary,
.cta-primary {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-bg);
  box-shadow: 0 10px 32px var(--color-accent-soft);
}

.button-primary:hover,
.cta-primary:hover {
  border-color: var(--color-text);
  background: var(--color-text);
}

.button-secondary,
.cta-secondary {
  background: var(--color-panel);
}

.button-secondary:hover,
.cta-secondary:hover {
  border-color: var(--color-border-bright);
  background: var(--color-panel-raised);
}

.button-quiet {
  min-height: 40px;
  padding-inline: 16px;
  color: var(--color-muted);
}

.button-quiet:hover {
  color: var(--color-text);
}

.button[aria-disabled="true"],
.button:disabled {
  opacity: 0.46;
  cursor: not-allowed;
  transform: none;
}

.cta-arrow {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 16px;
}

.panel,
.card {
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel);
}

.panel-raised,
.card-raised {
  border-color: var(--color-border-bright);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-panel);
}

.panel-pad,
.card-pad {
  padding: clamp(20px, 3vw, 32px);
}

.badge,
.tag,
.fact-chip {
  max-width: 100%;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 9px;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel-raised);
  color: var(--color-warn);
  font-family: var(--font-mono);
  font-size: 10px;
  line-height: 1;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.badge-accent {
  border-color: var(--color-accent-dark);
  color: var(--color-accent);
}

.status-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 10px var(--color-accent-glow);
}

.site-header {
  position: relative;
  z-index: 50;
  height: var(--header-height);
  border-bottom: var(--border-thin) solid var(--color-border);
  background: var(--color-overlay);
  backdrop-filter: blur(18px);
}

.header-inner {
  width: 100%;
  max-width: calc(var(--page-width) + (var(--gutter) * 2));
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 26px;
}

.brand {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 11px;
  min-width: 194px;
}

.brand-logo {
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
}

.brand-copy {
  display: flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
}

.brand-latin {
  color: var(--color-text);
  font-size: 17px;
  font-weight: 720;
  letter-spacing: -0.02em;
}

.brand-cn {
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 470;
}

.primary-nav {
  flex: 1 1 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 3px;
}

.nav-link {
  min-height: 36px;
  padding: 9px 11px;
  display: inline-flex;
  align-items: center;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 520;
  line-height: 1;
  white-space: nowrap;
  transition:
    color var(--transition-fast),
    background var(--transition-fast),
    border-color var(--transition-fast);
}

.nav-link:hover {
  background: var(--color-panel-raised);
  color: var(--color-text);
}

.nav-link.is-active {
  border-color: var(--color-border);
  background: var(--color-panel-raised);
  color: var(--color-text);
}

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

.language-control {
  position: relative;
}

.language-switch {
  min-height: 42px;
  padding: 9px 11px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-muted);
  font-size: 12px;
  cursor: pointer;
}

.language-switch:hover,
.language-switch[aria-expanded="true"] {
  border-color: var(--color-border);
  color: var(--color-text);
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  width: 170px;
  padding: 7px;
  border: var(--border-thin) solid var(--color-border-bright);
  border-radius: var(--radius-sm);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-panel);
}

.language-menu a {
  min-height: 40px;
  padding: 9px 10px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-xs);
  color: var(--color-muted);
  font-size: 13px;
}

.language-menu a:hover,
.language-menu a.is-current {
  background: var(--color-panel-soft);
  color: var(--color-text);
}

.login-button {
  min-height: 42px;
  padding: 10px 17px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: var(--border-thin) solid var(--color-border-bright);
  border-radius: var(--radius-sm);
  background: var(--color-panel-raised);
  color: var(--color-text);
  font-size: 13px;
  font-weight: 620;
  white-space: nowrap;
  transition:
    border-color var(--transition-fast),
    background var(--transition-fast);
}

.login-button:hover {
  border-color: var(--color-accent-dark);
  background: var(--color-panel-soft);
}

.menu-toggle {
  min-width: 44px;
  min-height: 44px;
  padding: 10px;
  display: none;
  place-items: center;
  border: var(--border-thin) solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  cursor: pointer;
}

.menu-toggle-lines,
.menu-toggle-lines::before,
.menu-toggle-lines::after {
  width: 18px;
  height: var(--border-thin);
  display: block;
  background: var(--color-text);
}

.menu-toggle-lines {
  position: relative;
}

.menu-toggle-lines::before,
.menu-toggle-lines::after {
  content: "";
  position: absolute;
  left: 0;
}

.menu-toggle-lines::before {
  top: -6px;
}

.menu-toggle-lines::after {
  top: 6px;
}

.mobile-drawer {
  display: none;
}

.nav-veil {
  display: none;
}

.site-footer {
  position: relative;
  overflow-x: clip;
  border-top: var(--border-thin) solid var(--color-border);
  background: var(--color-panel);
}

.footer-main {
  padding-top: 64px;
  padding-bottom: 50px;
  display: grid;
  grid-template-columns: minmax(250px, 1.25fr) repeat(3, minmax(150px, 1fr));
  gap: 44px;
}

.footer-brand p {
  max-width: 360px;
  margin: 18px 0 0;
  color: var(--color-muted);
  font-size: 14px;
}

.footer-heading {
  margin: 0 0 16px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.footer-links {
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
  list-style: none;
}

.footer-links a {
  color: var(--color-muted);
  font-size: 13px;
}

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

.footer-bottom {
  min-height: 66px;
  padding-top: 18px;
  padding-bottom: 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-top: var(--border-thin) solid var(--color-border);
  color: var(--color-subtle);
  font-family: var(--font-mono);
  font-size: 10px;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-legal a:hover {
  color: var(--color-text);
}

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

.prose > * {
  max-width: 100%;
}

.prose h2 {
  margin-top: 2.1em;
  scroll-margin-top: 120px;
}

.prose h3 {
  margin-top: 1.8em;
  scroll-margin-top: 120px;
}

.prose strong {
  color: var(--color-text);
}

.prose a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-color: var(--color-accent-dark);
  text-underline-offset: 3px;
}

.prose li {
  margin-bottom: 0.55em;
}

.prose blockquote {
  margin-inline: 0;
}

.prose > .data-table {
  min-width: 0;
  max-width: 100%;
  display: block;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.reveal {
  transition:
    opacity var(--transition-slow),
    transform var(--transition-slow);
}

.reveal.pending {
  opacity: 0;
  transform: translateY(16px);
}

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

.tilt,
.card-tilt {
  transform: rotate(-0.35deg);
}

@media (max-width: 1180px) {
  .primary-nav {
    gap: 0;
  }

  .nav-link {
    padding-inline: 8px;
  }

  .brand {
    min-width: auto;
  }

  .brand-cn {
    display: none;
  }
}

@media (max-width: 980px) {
  .site-header {
    height: 68px;
  }

  .header-inner {
    gap: 12px;
  }

  .primary-nav,
  .language-control {
    display: none;
  }

  .header-tools {
    margin-left: auto;
  }

  .menu-toggle {
    display: grid;
  }

  .mobile-drawer {
    position: fixed;
    z-index: 4;
    top: 68px;
    right: 0;
    left: 0;
    max-height: calc(100dvh - 68px);
    padding: 12px var(--gutter) 24px;
    overflow-y: auto;
    overscroll-behavior: contain;
    border-bottom: var(--border-thin) solid var(--color-border-bright);
    background: var(--color-panel-raised);
  }

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

  .mobile-drawer-list,
  .mobile-language-list {
    margin: 0;
    padding: 0;
    list-style: none;
  }

  .mobile-drawer-list a,
  .mobile-language-list a {
    width: 100%;
    min-height: 48px;
    padding: 12px;
    display: flex;
    align-items: center;
    border-bottom: var(--border-thin) solid var(--color-border);
    color: var(--color-muted);
    font-size: 15px;
  }

  .mobile-drawer-list a.is-active,
  .mobile-drawer-list a:hover,
  .mobile-language-list a.is-current,
  .mobile-language-list a:hover {
    color: var(--color-text);
    background: var(--color-panel-soft);
  }

  .mobile-language-title {
    margin: 20px 12px 5px;
    color: var(--color-subtle);
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
  }

  .nav-veil {
    position: fixed;
    z-index: 1;
    inset: 68px 0 0;
    background: var(--color-veil);
  }

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

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

@media (max-width: 768px) {
  :root {
    --display-size: clamp(28px, 9.5vw, 40px);
    --body-size: 16px;
    --section-space: 72px;
    --toc-top: 76px;
  }

  h1,
  .hero-title {
    line-height: 1.14;
    letter-spacing: -0.02em;
  }

  .title-nowrap {
    white-space: normal;
  }

  h2 {
    font-size: clamp(30px, 8vw, 40px);
  }

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

  .section-heading {
    margin-bottom: 32px;
  }

  .absolute-caption,
  .decorative-label,
  .mobile-hide-decoration {
    display: none !important;
  }
}

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
  }

  body {
    background-size: 48px 48px;
  }

  .brand-copy {
    display: none;
  }

  .brand {
    min-width: 36px;
  }

  .login-button {
    min-height: 44px;
    padding-inline: 13px;
  }

  .grid-two,
  .grid-three,
  .grid-four,
  .footer-main {
    grid-template-columns: minmax(0, 1fr);
  }

  .button,
  .cta {
    max-width: 100%;
  }

  .footer-main {
    gap: 34px;
  }

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

  .tilt,
  .card-tilt,
  [class*="tilt"] {
    transform: none;
  }

  .absolute-decoration,
  .section-glow,
  .decorative-disc,
  .watermark {
    max-width: 100%;
    inset-inline: 0;
  }
}

@media (max-width: 380px) {
  .header-inner {
    gap: 7px;
  }

  .login-button {
    padding-inline: 10px;
    font-size: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

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

  .reveal,
  .reveal.pending,
  .reveal.shown {
    opacity: 1;
    transform: none;
  }
}