:root {
  --color-bg: #090A0A;
  --color-panel: #131515;
  --color-panel-strong: #1B1E1D;
  --color-border: #454A47;
  --color-border-bright: #717873;
  --color-accent: #FF4B22;
  --color-accent-dark: #B92A12;
  --color-text: #F3F5F2;
  --color-text-muted: #A0A6A2;
  --color-success: #20D6A3;
  --color-warn: #FFB13B;
  --color-error: #FF365B;
  --color-black: #000000;
  --color-transparent: transparent;
  --color-accent-soft: rgba(255, 75, 34, 0.15);
  --color-accent-line: rgba(255, 75, 34, 0.42);
  --color-accent-shadow: rgba(185, 42, 18, 0.55);
  --color-text-soft: rgba(243, 245, 242, 0.72);
  --color-text-faint: rgba(243, 245, 242, 0.12);
  --color-grid: rgba(160, 166, 162, 0.10);
  --color-grid-strong: rgba(160, 166, 162, 0.19);
  --color-panel-glow: rgba(255, 75, 34, 0.08);
  --color-success-soft: rgba(32, 214, 163, 0.15);
  --color-success-shadow: rgba(32, 214, 163, 0.36);
  --color-overlay: rgba(0, 0, 0, 0.72);
  --color-focus: rgba(255, 177, 59, 0.42);
  --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-none: 0;
  --radius-small: 3px;
  --radius-pill: 999px;
  --header-height: 76px;
  --header-height-mobile: 64px;
  --page-width: 1360px;
  --reading-width: 768px;
  --gutter: clamp(16px, 3vw, 32px);
  --section-space: clamp(72px, 9vw, 128px);
  --cut-small: 10px;
  --cut-medium: 16px;
  --shadow-hard: 8px 8px 0 var(--color-black);
  --shadow-accent: 10px 10px 0 var(--color-accent-dark);
  --shadow-success: 7px 7px 0 var(--color-success-shadow);
  --ease-industrial: cubic-bezier(0.22, 0.75, 0.28, 1);
  --transition-fast: 180ms;
  --transition-reveal: 620ms;
  --toc-top: 76px;
  --toc-height: 58px;
}

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

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

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 0;
  min-height: 100vh;
  margin: 0;
  overflow-x: clip;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

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

img {
  border: 0;
}

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

button,
input,
select,
textarea {
  margin: 0;
  color: inherit;
  font: inherit;
}

button,
summary {
  -webkit-tap-highlight-color: var(--color-transparent);
}

button {
  cursor: pointer;
}

table {
  border-collapse: collapse;
  border-spacing: 0;
}

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

p,
h1,
h2,
h3,
h4,
ul,
ol,
blockquote,
pre,
table {
  margin-top: 0;
}

p,
li,
td,
th,
h1,
h2,
h3,
h4 {
  overflow-wrap: break-word;
}

code {
  font-family: var(--font-mono);
  overflow-wrap: anywhere;
}

pre {
  max-width: 100%;
  padding: 18px;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  background: var(--color-black);
  color: var(--color-text);
  font-family: var(--font-mono);
  line-height: 1.65;
  tab-size: 2;
  -webkit-overflow-scrolling: touch;
}

pre code {
  overflow-wrap: normal;
  white-space: pre;
}

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

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

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

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

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

.section-compact {
  padding-top: calc(var(--section-space) * 0.6);
  padding-bottom: calc(var(--section-space) * 0.6);
  overflow-x: clip;
}

.section-heading {
  max-width: 820px;
  margin-bottom: 42px;
}

.section-heading p {
  max-width: 680px;
  margin: 16px 0 0;
  color: var(--color-text-muted);
}

.kicker,
.eyebrow {
  display: inline-flex;
  min-height: 30px;
  max-width: 100%;
  align-items: center;
  gap: 9px;
  padding: 5px 13px 5px 10px;
  overflow: hidden;
  border: 1px solid var(--color-border-bright);
  background: var(--color-panel);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  clip-path: polygon(0 0, calc(100% - var(--cut-small)) 0, 100% var(--cut-small), 100% 100%, 0 100%);
}

.status-dot,
.eyebrow-dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border: 2px solid var(--color-success);
  border-radius: var(--radius-pill);
  background: var(--color-success);
  box-shadow: 0 0 0 4px var(--color-success-soft);
}

h1,
h2,
h3,
h4 {
  color: var(--color-text);
  font-family: var(--font-display);
}

h1,
.hero-title {
  margin-bottom: 0;
  font-size: clamp(52px, 5.2vw, 72px);
  font-weight: 850;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(32px, 3.2vw, 48px);
  font-weight: 820;
  line-height: 1.16;
  letter-spacing: -0.015em;
}

h3 {
  margin-bottom: 12px;
  font-size: clamp(22px, 2.2vw, 30px);
  line-height: 1.28;
}

h4 {
  margin-bottom: 10px;
  font-size: 18px;
}

.lead {
  color: var(--color-text-soft);
  font-size: clamp(18px, 1.6vw, 22px);
  line-height: 1.65;
}

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

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

.accent-text {
  color: var(--color-accent);
  text-shadow: 4px 4px 0 var(--color-accent-dark);
}

.success-text {
  color: var(--color-success);
}

.button,
.cta {
  display: inline-flex;
  min-height: 52px;
  max-width: 100%;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 10px 24px;
  border: 2px solid var(--color-transparent);
  background: var(--color-panel);
  color: var(--color-text);
  font-size: 15px;
  font-weight: 800;
  line-height: 1.2;
  text-align: center;
  clip-path: polygon(0 0, calc(100% - var(--cut-medium)) 0, 100% var(--cut-medium), 100% 100%, var(--cut-medium) 100%, 0 calc(100% - var(--cut-medium)));
  transition:
    transform var(--transition-fast) var(--ease-industrial),
    background var(--transition-fast) ease,
    border-color var(--transition-fast) ease;
}

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

.button-primary,
.cta-primary {
  border-color: var(--color-success);
  background: var(--color-success);
  color: var(--color-bg);
  box-shadow: var(--shadow-success);
}

.button-secondary,
.cta-secondary {
  border-color: var(--color-border-bright);
  background: var(--color-panel);
  color: var(--color-text);
  box-shadow: 7px 7px 0 var(--color-black);
}

.button-accent {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-bg);
  box-shadow: var(--shadow-accent);
}

.button-quiet {
  min-height: 44px;
  border-color: var(--color-border);
  background: var(--color-transparent);
  color: var(--color-text-muted);
  clip-path: none;
}

.button[disabled],
.button.is-disabled {
  border-color: var(--color-border);
  background: var(--color-panel-strong);
  color: var(--color-text-muted);
  box-shadow: none;
  cursor: not-allowed;
  opacity: 0.62;
  transform: none;
}

.button-arrow {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 18px;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
}

.panel,
.card {
  position: relative;
  border: 2px solid var(--color-border);
  background: var(--color-panel);
  box-shadow: var(--shadow-hard);
  clip-path: polygon(0 0, calc(100% - var(--cut-medium)) 0, 100% var(--cut-medium), 100% 100%, var(--cut-medium) 100%, 0 calc(100% - var(--cut-medium)));
}

.panel {
  padding: clamp(22px, 3vw, 38px);
}

.card {
  padding: 24px;
}

.panel::before,
.card::before {
  position: absolute;
  top: -2px;
  left: 22px;
  width: 54px;
  height: 4px;
  content: "";
  background: var(--color-accent);
}

.badge,
.tag,
.fact-chip {
  display: inline-flex;
  min-height: 28px;
  max-width: 100%;
  align-items: center;
  gap: 7px;
  padding: 4px 10px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: var(--color-panel-strong);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  line-height: 1.35;
  text-overflow: ellipsis;
  white-space: nowrap;
}

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

.badge-success {
  border-color: var(--color-success);
  background: var(--color-success-soft);
  color: var(--color-success);
}

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

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
}

.fact-band {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border: 2px solid var(--color-border);
  background: var(--color-panel);
  box-shadow: var(--shadow-hard);
}

.fact-band-item {
  min-width: 0;
  padding: 18px 20px;
  border-left: 1px solid var(--color-border);
}

.fact-band-item:first-child {
  border-left: 0;
}

.fact-band-value {
  display: block;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 800;
}

.fact-band-label {
  display: block;
  margin-top: 4px;
  color: var(--color-text-muted);
  font-size: 12px;
}

.site-header {
  position: relative;
  z-index: 100;
  min-height: var(--header-height);
  border-bottom: 2px solid var(--color-border);
  background: var(--color-bg);
}

.topbar-inner {
  width: min(100%, calc(var(--page-width) + var(--gutter) * 2));
  min-height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: stretch;
}

.site-brand {
  display: flex;
  min-width: 190px;
  align-items: center;
  flex: 0 0 auto;
  gap: 11px;
  padding-right: 22px;
  border-right: 1px solid var(--color-border);
}

.site-brand img {
  width: 38px;
  height: 38px;
  flex: 0 0 auto;
  filter: drop-shadow(3px 3px 0 var(--color-accent-dark));
}

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

.brand-latin {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 850;
  letter-spacing: -0.02em;
}

.brand-cn {
  color: var(--color-text-muted);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.06em;
}

.desktop-nav {
  display: flex;
  min-width: 0;
  flex: 1 1 auto;
  align-items: stretch;
  justify-content: center;
  padding-inline: 8px;
}

.nav-link {
  position: relative;
  display: flex;
  min-width: 0;
  align-items: center;
  justify-content: center;
  padding-inline: 11px;
  color: var(--color-text-muted);
  font-size: 13px;
  font-weight: 650;
  white-space: nowrap;
  transition: color var(--transition-fast) ease;
}

.nav-link::after {
  position: absolute;
  right: 11px;
  bottom: -2px;
  left: 11px;
  height: 3px;
  content: "";
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: right center;
  transition: transform var(--transition-fast) ease;
}

.nav-link:hover,
.nav-link.is-active,
.nav-link[aria-current="page"] {
  color: var(--color-text);
}

.nav-link:hover::after,
.nav-link.is-active::after,
.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  transform-origin: left center;
}

.header-tools {
  position: relative;
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 10px;
  padding-left: 14px;
  border-left: 1px solid var(--color-border);
}

.language-control {
  position: relative;
}

.language-button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  gap: 6px;
  padding: 0 8px;
  border: 0;
  background: var(--color-transparent);
  color: var(--color-text-muted);
  font-size: 12px;
}

.language-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  z-index: 130;
  width: 170px;
  padding: 6px;
  border: 2px solid var(--color-border);
  background: var(--color-panel);
  box-shadow: var(--shadow-hard);
}

.language-menu[hidden] {
  display: none;
}

.language-menu a {
  display: flex;
  min-height: 44px;
  align-items: center;
  padding: 8px 12px;
  color: var(--color-text-muted);
  font-size: 13px;
}

.language-menu a:hover,
.language-menu a[aria-current="true"] {
  background: var(--color-panel-strong);
  color: var(--color-text);
}

.login-button {
  display: inline-flex;
  min-width: 68px;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding: 8px 14px;
  border: 2px solid var(--color-success);
  background: var(--color-success);
  color: var(--color-bg);
  font-size: 13px;
  font-weight: 850;
  clip-path: polygon(0 0, calc(100% - var(--cut-small)) 0, 100% var(--cut-small), 100% 100%, var(--cut-small) 100%, 0 calc(100% - var(--cut-small)));
  box-shadow: 4px 4px 0 var(--color-success-shadow);
}

.menu-toggle {
  display: none;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 8px;
  border: 1px solid var(--color-border);
  background: var(--color-panel);
}

.menu-toggle-lines,
.menu-toggle-lines::before,
.menu-toggle-lines::after {
  width: 20px;
  height: 2px;
  background: var(--color-text);
}

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

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

.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: 2px solid var(--color-border);
  background:
    linear-gradient(var(--color-grid) 1px, var(--color-transparent) 1px),
    linear-gradient(90deg, var(--color-grid) 1px, var(--color-transparent) 1px),
    var(--color-panel);
  background-size: 48px 48px;
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(240px, 1.2fr) minmax(160px, 0.8fr) minmax(260px, 1.2fr) minmax(170px, 0.7fr);
  gap: 42px;
  padding-top: 64px;
  padding-bottom: 48px;
}

.footer-brand {
  max-width: 330px;
}

.footer-brand-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-brand-row img {
  width: 42px;
  height: 42px;
  flex: 0 0 auto;
}

.footer-brand-name {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 850;
}

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

.footer-heading {
  margin-bottom: 16px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
}

.footer-links {
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-links li + li {
  margin-top: 8px;
}

.footer-links a {
  display: inline-flex;
  min-height: 32px;
  align-items: center;
  color: var(--color-text-muted);
  font-size: 14px;
}

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

.footer-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.footer-keywords a {
  display: inline-flex;
  min-height: 30px;
  max-width: 100%;
  align-items: center;
  padding: 4px 9px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 10px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 20px;
  padding-bottom: 24px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 11px;
}

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

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

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

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

.tilt,
.tilt-panel {
  transform: rotate(-0.45deg);
}

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

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

.prose h2 {
  margin-top: 2.4em;
}

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

.prose a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

.prose a.button-primary {
  color: var(--color-bg);
  text-decoration: none;
}

.prose blockquote {
  margin-inline: 0;
}

.prose table {
  width: 100%;
}

body:has(.toc-tabs) section[id] {
  scroll-margin-top: calc(var(--toc-top) + var(--toc-height) + 18px);
}

@media (max-width: 1260px) {
  .nav-link {
    padding-inline: 8px;
    font-size: 12px;
  }

  .nav-link::after {
    right: 8px;
    left: 8px;
  }

  .site-brand {
    min-width: 160px;
    padding-right: 14px;
  }

  .brand-cn {
    display: none;
  }
}

@media (max-width: 980px) {
  :root {
    --toc-top: 64px;
  }

  .site-header,
  .topbar-inner {
    min-height: var(--header-height-mobile);
  }

  .topbar-inner {
    align-items: center;
  }

  .site-brand {
    min-width: 0;
    height: var(--header-height-mobile);
    padding-right: 12px;
    border-right: 0;
  }

  .site-brand img {
    width: 34px;
    height: 34px;
  }

  .brand-latin {
    font-size: 18px;
  }

  .desktop-nav {
    display: none;
  }

  .header-tools {
    margin-left: auto;
    padding-left: 8px;
    border-left: 0;
  }

  .header-tools .language-control {
    display: none;
  }

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

  .mobile-drawer {
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    z-index: 120;
    max-height: calc(100dvh - var(--header-height-mobile));
    overflow-y: auto;
    overscroll-behavior: contain;
    border-top: 1px solid var(--color-border);
    border-bottom: 2px solid var(--color-border);
    background: var(--color-panel);
    box-shadow: var(--shadow-hard);
  }

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

  .mobile-drawer ul {
    margin: 0;
    padding: 10px var(--gutter);
    list-style: none;
  }

  .mobile-drawer li {
    border-bottom: 1px solid var(--color-border);
  }

  .mobile-drawer a {
    display: flex;
    width: 100%;
    min-height: 48px;
    align-items: center;
    justify-content: space-between;
    padding: 10px 8px;
    color: var(--color-text-muted);
  }

  .mobile-drawer a:hover,
  .mobile-drawer a[aria-current="page"],
  .mobile-drawer a[aria-current="true"] {
    color: var(--color-text);
  }

  .mobile-language-title {
    padding: 16px 8px 4px;
    color: var(--color-accent);
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.12em;
  }

  .nav-veil {
    position: fixed;
    inset: var(--header-height-mobile) 0 0;
    z-index: 90;
    border: 0;
    background: var(--color-overlay);
  }

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

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

  .fact-band-item:nth-child(3) {
    border-left: 0;
  }

  .fact-band-item:nth-child(n + 3) {
    border-top: 1px solid var(--color-border);
  }

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

@media (max-width: 768px) {
  h1,
  .hero-title {
    font-size: clamp(28px, 9.5vw, 40px);
    line-height: 1.14;
    letter-spacing: -0.015em;
  }

  h2 {
    font-size: clamp(28px, 8vw, 38px);
  }

  .section-heading {
    margin-bottom: 30px;
  }

  .absolute-caption,
  .decorative-label,
  .section-coordinate {
    display: none;
  }

  .button-row {
    align-items: stretch;
  }

  .button-row .button,
  .button-row .cta {
    flex: 1 1 160px;
  }

  .footer-main {
    gap: 34px 22px;
    padding-top: 48px;
  }
}

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
    --section-space: 70px;
  }

  .wrap,
  .reading-wrap {
    width: 100%;
    padding-inline: var(--gutter);
  }

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

  .panel,
  .card {
    padding: 20px;
    box-shadow: 5px 5px 0 var(--color-black);
  }

  .fact-band {
    grid-template-columns: 1fr;
  }

  .fact-band-item,
  .fact-band-item:nth-child(3) {
    border-left: 0;
  }

  .fact-band-item:nth-child(n + 2) {
    border-top: 1px solid var(--color-border);
  }

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

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

  .login-button {
    min-width: 62px;
    padding-inline: 10px;
  }

  .brand-copy {
    gap: 4px;
  }

  .brand-cn {
    display: none;
  }
}

@media (max-width: 370px) {
  .site-brand img {
    width: 31px;
    height: 31px;
  }

  .brand-latin {
    font-size: 17px;
  }

  .header-tools {
    gap: 6px;
  }

  .login-button {
    min-width: 56px;
    font-size: 12px;
  }
}

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

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

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