:root {
  --color-bg: #0B0B0C;
  --color-panel: #151516;
  --color-panel-raised: #202022;
  --color-panel-soft: #29292B;
  --color-border: #373739;
  --color-border-strong: #555153;
  --color-accent: #F0443E;
  --color-accent-dark: #B92320;
  --color-text: #FAFAF8;
  --color-text-muted: #AAA6A1;
  --color-text-faint: #77736F;
  --color-success: #56B881;
  --color-warn: #D9A441;
  --color-error: #E05A54;
  --color-transparent: transparent;
  --color-overlay: rgb(11 11 12 / 82%);
  --color-shadow: rgb(0 0 0 / 46%);
  --color-accent-soft: rgb(240 68 62 / 12%);
  --color-success-soft: rgb(86 184 129 / 12%);
  --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: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 26px;
  --radius-pill: 999px;
  --page-width: 1380px;
  --content-width: 1120px;
  --article-width: 820px;
  --gutter: 24px;
  --header-height: 74px;
  --toc-top: 86px;
  --section-space: 96px;
  --transition-fast: 160ms ease;
  --transition-base: 280ms ease;
  --shadow-raised: 0 24px 64px var(--color-shadow);
  --shadow-small: 0 12px 28px var(--color-shadow);
}

*,
*::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-color: 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;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -2;
  content: "";
  pointer-events: none;
  background-image:
    linear-gradient(var(--color-transparent) 95%, var(--color-panel) 95%),
    linear-gradient(90deg, var(--color-transparent) 95%, var(--color-panel) 95%);
  background-size: 48px 48px;
}

body::after {
  position: fixed;
  inset: 0;
  z-index: -1;
  content: "";
  pointer-events: none;
  background: linear-gradient(112deg, var(--color-bg) 0%, var(--color-bg) 42%, var(--color-panel) 76%, var(--color-bg) 100%);
  opacity: .78;
}

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

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

img {
  height: auto;
}

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

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

button {
  cursor: pointer;
}

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

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

p {
  margin-bottom: 1.15em;
}

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

li + li {
  margin-top: .42em;
}

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  line-height: 1.12;
  text-wrap: balance;
}

h1 {
  margin-bottom: 24px;
  font-size: clamp(3.25rem, 6vw, 4.2rem);
  font-weight: 820;
  letter-spacing: -.065em;
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 780;
  letter-spacing: -.045em;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(1.25rem, 2.4vw, 1.65rem);
  font-weight: 720;
  letter-spacing: -.025em;
}

h4 {
  margin-bottom: 10px;
  font-size: 1rem;
  font-weight: 700;
}

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

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

hr {
  margin: 40px 0;
  border: 0;
  border-top: 1px solid var(--color-border);
}

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

:not(pre) > code {
  max-width: 100%;
  padding: .12em .36em;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  background: var(--color-panel-raised);
  overflow-wrap: anywhere;
  word-break: break-word;
}

pre {
  max-width: 100%;
  padding: 18px;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  color: var(--color-text-muted);
  font-size: .88rem;
  line-height: 1.65;
  overscroll-behavior-inline: contain;
  -webkit-overflow-scrolling: touch;
}

pre code {
  display: block;
  min-width: max-content;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--color-border);
  text-align: left;
  vertical-align: top;
}

th {
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .04em;
  text-transform: uppercase;
}

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

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

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

.content-wrap {
  width: min(100%, var(--content-width));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.article-wrap {
  width: min(100%, var(--article-width));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

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

.section-compact {
  padding-top: 56px;
  padding-bottom: 56px;
}

.section-heading {
  max-width: 780px;
  margin-bottom: 38px;
}

.section-kicker,
.mono-label {
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .09em;
  text-transform: uppercase;
}

.section-kicker {
  display: block;
  margin-bottom: 12px;
}

.lead {
  max-width: 720px;
  color: var(--color-text-muted);
  font-size: clamp(1.05rem, 2vw, 1.24rem);
  line-height: 1.75;
}

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

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

.display-accent {
  display: block;
  color: var(--color-accent);
}

.eyebrow {
  width: max-content;
  max-width: 100%;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 11px 7px 8px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  color: var(--color-text-muted);
  background: var(--color-panel);
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .07em;
  text-transform: uppercase;
}

.eyebrow-dot,
.status-dot {
  width: 8px;
  height: 8px;
  flex-shrink: 0;
  border: 2px solid var(--color-success);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
}

.badge,
.tag,
.fact-chip {
  max-width: 100%;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.badge,
.tag {
  padding: 5px 9px;
  color: var(--color-text-muted);
  background: var(--color-panel);
  font-family: var(--font-mono);
  font-size: .7rem;
}

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

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

.fact-chip {
  padding: 9px 12px;
  color: var(--color-text-muted);
  background: var(--color-panel);
  font-family: var(--font-mono);
  font-size: .74rem;
}

.button,
.login-link,
.hero-button {
  min-height: 44px;
  padding: 0 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  color: var(--color-text);
  font-weight: 720;
  line-height: 1;
  text-align: center;
  transition: border-color var(--transition-fast), background-color var(--transition-fast), transform var(--transition-fast);
}

.button:hover,
.hero-button:hover {
  border-color: var(--color-text-muted);
  background: var(--color-panel-raised);
  transform: translateY(-1px);
}

.button-primary,
.hero-button-primary {
  border-color: var(--color-accent);
  background: var(--color-accent);
}

.button-primary:hover,
.hero-button-primary:hover {
  border-color: var(--color-accent-dark);
  background: var(--color-accent-dark);
}

.button-quiet {
  border-color: var(--color-border);
  color: var(--color-text-muted);
  background: var(--color-transparent);
}

.button:disabled,
.button[aria-disabled="true"] {
  cursor: not-allowed;
  opacity: .46;
  transform: none;
}

.button-arrow {
  flex-shrink: 0;
  font-family: var(--font-mono);
}

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

.panel,
.card {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
}

.panel {
  padding: 28px;
}

.card {
  padding: 24px;
  transition: border-color var(--transition-fast), background-color var(--transition-fast), transform var(--transition-fast);
}

.card:hover {
  border-color: var(--color-border-strong);
  background: var(--color-panel-raised);
  transform: translateY(-2px);
}

.grid-two,
.grid-three,
.grid-four {
  display: grid;
  gap: 18px;
}

.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));
}

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

.prose h2,
.prose h3,
.prose h4 {
  scroll-margin-top: var(--toc-top);
}

.prose h2 {
  margin-top: 2.3em;
}

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

.prose a {
  color: var(--color-text);
  text-decoration: underline;
  text-decoration-color: var(--color-accent);
  text-underline-offset: .2em;
}

.prose blockquote {
  margin-inline: 0;
}

.prose ol.steps {
  padding: 0;
  list-style: none;
  counter-reset: guide-step;
}

.prose ol.steps > li {
  position: relative;
  min-height: 38px;
  padding-left: 52px;
  counter-increment: guide-step;
}

.prose ol.steps > li::before {
  position: absolute;
  top: 0;
  left: 0;
  width: 34px;
  height: 34px;
  display: grid;
  content: counter(guide-step);
  place-items: center;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-pill);
  color: var(--color-text);
  background: var(--color-accent-soft);
  font-family: var(--font-mono);
  font-size: .75rem;
}

.reveal {
  transition: opacity 560ms ease, transform 560ms ease;
}

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

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

.site-header {
  position: relative;
  z-index: 100;
  width: min(calc(100% - 48px), var(--page-width));
  height: var(--header-height);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 226px minmax(0, 1fr) auto;
  align-items: center;
  gap: 18px;
  border-bottom: 1px solid var(--color-border);
}

.site-brand {
  width: max-content;
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand-logo {
  width: 38px;
  height: 38px;
  flex-shrink: 0;
  border-radius: var(--radius-md);
}

.brand-word {
  font-family: var(--font-display);
  font-size: 1.12rem;
  font-weight: 820;
  letter-spacing: -.03em;
}

.brand-local {
  color: var(--color-text-muted);
  font-size: .8rem;
  font-weight: 500;
}

.desktop-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2px;
  white-space: nowrap;
}

.desktop-nav a {
  padding: 8px 10px;
  border: 1px solid var(--color-transparent);
  border-radius: var(--radius-pill);
  color: var(--color-text-muted);
  font-size: .8rem;
  line-height: 1;
  transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
}

.desktop-nav a:hover {
  border-color: var(--color-border);
  background: var(--color-panel);
  color: var(--color-text);
}

.desktop-nav a[aria-current="page"] {
  border-color: var(--color-border);
  background: var(--color-panel-raised);
  color: var(--color-text);
}

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

.login-link {
  min-height: 36px;
  padding-inline: 14px;
  border-color: var(--color-text);
  border-radius: var(--radius-pill);
  background: var(--color-text);
  color: var(--color-bg);
  font-size: .8rem;
}

.language-toggle {
  min-height: 36px;
  padding: 0 13px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-text-muted);
  font-size: .78rem;
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 46px;
  z-index: 130;
  min-width: 168px;
  padding: 7px;
  display: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-small);
}

.language-menu.open {
  display: block;
}

.language-menu a {
  min-height: 40px;
  padding: 8px 10px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-xs);
  color: var(--color-text-muted);
  font-size: .8rem;
}

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

.menu-toggle {
  width: 44px;
  min-width: 44px;
  height: 44px;
  min-height: 44px;
  padding: 0;
  display: none;
  place-items: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
}

.menu-toggle-lines,
.menu-toggle-lines::before,
.menu-toggle-lines::after {
  width: 18px;
  height: 2px;
  display: block;
  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 {
  margin-top: 88px;
  border-top: 1px solid var(--color-border);
  background: var(--color-panel);
}

.footer-main {
  padding-top: 58px;
  padding-bottom: 44px;
  display: grid;
  grid-template-columns: minmax(240px, 1.25fr) repeat(3, minmax(150px, 1fr));
  gap: 42px;
}

.footer-brand-copy {
  max-width: 360px;
  margin-top: 18px;
  color: var(--color-text-muted);
  font-size: .9rem;
}

.footer-title {
  margin-bottom: 15px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}

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

.footer-links a {
  width: fit-content;
  color: var(--color-text-muted);
  font-size: .87rem;
}

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

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

.footer-keywords a {
  max-width: 100%;
  padding: 5px 8px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: .68rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.footer-bottom {
  padding-top: 18px;
  padding-bottom: 22px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-faint);
  font-family: var(--font-mono);
  font-size: .7rem;
}

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

.hero-preview {
  position: relative;
  min-height: 790px;
  overflow-x: clip;
}

.hero-grid {
  position: relative;
  z-index: 2;
  min-height: 790px;
  display: grid;
  grid-template-columns: 470px minmax(0, 1fr);
  gap: 42px;
  align-items: start;
  padding-top: 72px;
}

.hero-copy {
  position: relative;
  z-index: 3;
  padding-top: 10px;
}

.hero-copy h1 {
  max-width: 470px;
  margin: 24px 0 22px;
  font-size: clamp(3.8rem, 5.1vw, 4.2rem);
  line-height: .98;
}

.hero-actions {
  margin-bottom: 22px;
}

.hero-description {
  max-width: 448px;
  color: var(--color-text-muted);
  line-height: 1.72;
}

.trust-row {
  max-width: 452px;
  margin: 22px 0 0;
  padding: 14px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: .68rem;
}

.trust-item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.trust-item::before {
  width: 5px;
  height: 5px;
  flex-shrink: 0;
  content: "";
  border-radius: var(--radius-pill);
  background: var(--color-success);
}

body:has(.toc-tabs) section[id] {
  scroll-margin-top: calc(var(--toc-top) + 12px);
}

.toc-sticky-host {
  position: sticky;
  top: var(--toc-host-top, var(--toc-top));
  z-index: 40;
}

@media (max-width: 1280px) {
  .site-header {
    width: calc(100% - 32px);
    grid-template-columns: 190px minmax(0, 1fr) auto;
    gap: 10px;
  }

  .brand-local {
    display: none;
  }

  .desktop-nav a {
    padding-inline: 7px;
    font-size: .74rem;
  }

  .hero-grid {
    grid-template-columns: 430px minmax(0, 1fr);
    gap: 30px;
  }
}

@media (max-width: 980px) {
  :root {
    --header-height: 66px;
    --toc-top: 76px;
    --section-space: 72px;
  }

  .site-header {
    grid-template-columns: auto 1fr auto;
  }

  .desktop-nav {
    display: none;
  }

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

  .header-tools > .language-toggle,
  .header-tools > .language-menu {
    display: none;
  }

  .menu-toggle {
    display: grid;
  }

  .mobile-drawer {
    position: fixed;
    top: var(--header-height);
    right: 0;
    left: 0;
    z-index: 120;
    max-height: calc(100dvh - var(--header-height));
    padding: 12px var(--gutter) 24px;
    overflow-y: auto;
    overscroll-behavior: contain;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-panel);
  }

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

  .mobile-drawer a {
    width: 100%;
    min-height: 48px;
    padding: 11px 12px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--color-border);
    color: var(--color-text-muted);
  }

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

  .mobile-language-title {
    margin: 20px 12px 5px;
    color: var(--color-text-faint);
    font-family: var(--font-mono);
    font-size: .68rem;
    letter-spacing: .08em;
    text-transform: uppercase;
  }

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

  .hero-preview,
  .hero-grid {
    min-height: auto;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    padding-top: 56px;
    padding-bottom: 72px;
  }

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

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

@media (max-width: 640px) {
  :root {
    --gutter: 18px;
    --section-space: 58px;
  }

  body {
    font-size: 15px;
  }

  .site-header {
    width: 100%;
    padding-inline: var(--gutter);
    grid-template-columns: auto 1fr auto;
  }

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

  .brand-word {
    font-size: 1rem;
  }

  .login-link {
    min-height: 38px;
    padding-inline: 12px;
  }

  .hero-grid {
    padding-top: 38px;
  }

  .hero-copy h1,
  h1 {
    font-size: clamp(3rem, 15vw, 3.85rem);
  }

  .hero-actions,
  .button-row {
    align-items: stretch;
  }

  .hero-actions .hero-button {
    flex: 1 1 0;
    min-width: 0;
  }

  .trust-row {
    gap: 9px 13px;
  }

  .grid-two,
  .grid-three,
  .grid-four {
    grid-template-columns: 1fr;
  }

  .panel,
  .card {
    padding: 20px;
  }

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

  .footer-main {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .footer-bottom {
    flex-direction: column;
  }

  .prose pre {
    border-radius: var(--radius-xs);
  }
}

@media (max-width: 380px) {
  :root {
    --gutter: 16px;
  }

  .site-brand {
    gap: 7px;
  }

  .brand-local {
    display: none;
  }

  .login-link {
    padding-inline: 10px;
    font-size: .74rem;
  }

  .header-tools {
    gap: 6px;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto;
    transition-duration: .01ms;
  }

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