:root {
  --color-bg: #050B18;
  --color-panel: #0A1425;
  --color-panel-raised: #102038;
  --color-border: #1B3043;
  --color-accent: #07C160;
  --color-accent-dark: #079447;
  --color-text: #F2F6F3;
  --color-muted: #8EA1B3;
  --color-success: #07C160;
  --color-warn: #D6A84B;
  --color-error: #D9615D;
  --color-ocean-bright: #176C78;
  --color-ocean-mid: #0D4757;
  --color-ocean-dark: #082938;
  --color-land-bright: #17694F;
  --color-land-mid: #0D493C;
  --color-land-dark: #092E2D;
  --color-text-soft: color-mix(in srgb, var(--color-text) 78%, transparent);
  --color-text-faint: color-mix(in srgb, var(--color-text) 12%, transparent);
  --color-line: color-mix(in srgb, var(--color-text) 22%, transparent);
  --color-route: color-mix(in srgb, var(--color-accent) 68%, var(--color-text));
  --color-route-soft: color-mix(in srgb, var(--color-accent) 28%, transparent);
  --color-accent-soft: color-mix(in srgb, var(--color-accent) 13%, transparent);
  --color-accent-border: color-mix(in srgb, var(--color-accent) 30%, transparent);
  --color-panel-soft: color-mix(in srgb, var(--color-panel) 78%, transparent);
  --color-shadow: color-mix(in srgb, var(--color-bg) 76%, transparent);
  --color-shadow-deep: color-mix(in srgb, var(--color-bg) 92%, transparent);
  --color-overlay: color-mix(in srgb, var(--color-bg) 74%, transparent);
  --color-code: color-mix(in srgb, var(--color-panel-raised) 78%, var(--color-bg));
  --color-table-stripe: color-mix(in srgb, var(--color-panel-raised) 54%, transparent);
  --color-warn-soft: color-mix(in srgb, var(--color-warn) 14%, transparent);
  --color-error-soft: color-mix(in srgb, var(--color-error) 14%, transparent);
  --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-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 34px;
  --radius-pill: 999px;
  --radius-circle: 50%;
  --shadow-button: 0 14px 34px color-mix(in srgb, var(--color-accent) 18%, transparent);
  --shadow-panel: 0 22px 58px var(--color-shadow);
  --shadow-planet: 0 36px 72px var(--color-shadow-deep);
  --page-width: 1320px;
  --reading-width: 768px;
  --nav-height: 88px;
  --gutter: clamp(18px, 4vw, 32px);
  --section-space: clamp(76px, 9vw, 132px);
  --toc-top: 14px;
  --toc-height: 62px;
  --ease-soft: cubic-bezier(.22, .7, .22, 1);
  --ease-quick: cubic-bezier(.2, .8, .2, 1);
  --duration-fast: 180ms;
  --duration-slow: 680ms;
}

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

html {
  min-width: 0;
  scroll-behavior: smooth;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  text-size-adjust: 100%;
}

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 0;
  min-height: 100vh;
  margin: 0;
  overflow-x: clip;
  background:
    radial-gradient(circle at 13% 22%, var(--color-text-faint) 0 1px, transparent 1.5px),
    radial-gradient(circle at 29% 68%, var(--color-text-faint) 0 1px, transparent 1.5px),
    radial-gradient(circle at 59% 14%, var(--color-text-faint) 0 1px, transparent 1.5px),
    radial-gradient(circle at 74% 63%, var(--color-text-faint) 0 1px, transparent 1.5px),
    radial-gradient(circle at 91% 26%, var(--color-text-faint) 0 1px, transparent 1.5px),
    linear-gradient(180deg, var(--color-bg), var(--color-bg));
  background-size: 211px 211px, 307px 307px, 263px 263px, 367px 367px, 293px 293px, auto;
  color: var(--color-text);
  font-family: var(--font-body);
  line-height: 1.7;
}

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

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

img,
svg {
  display: block;
}

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

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

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

button {
  border: 0;
}

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

code {
  overflow-wrap: anywhere;
  word-break: break-word;
}

pre {
  max-width: 100%;
  margin: 1.5rem 0;
  padding: 18px 20px;
  overflow-x: auto;
  border-radius: var(--radius-md);
  background: var(--color-code);
  color: var(--color-text-soft);
  line-height: 1.65;
  overscroll-behavior-inline: contain;
  -webkit-overflow-scrolling: touch;
}

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

table {
  border-collapse: collapse;
}

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

.wrap {
  max-width: calc(var(--page-width) + var(--gutter) + var(--gutter));
}

.reading-wrap {
  max-width: calc(var(--reading-width) + var(--gutter) + var(--gutter));
}

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

.section-compact {
  padding-top: calc(var(--section-space) * .62);
  padding-bottom: calc(var(--section-space) * .62);
}

.section-head {
  max-width: 780px;
  margin-bottom: 42px;
}

.section-kicker {
  margin: 0 0 12px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: .76rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

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

h1 {
  margin-bottom: 24px;
  font-size: clamp(3.25rem, 6vw, 4.875rem);
  font-weight: 760;
  line-height: 1.04;
  letter-spacing: -.052em;
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(2rem, 4vw, 3.35rem);
  font-weight: 720;
  line-height: 1.12;
  letter-spacing: -.038em;
}

h3 {
  margin-bottom: 12px;
  font-size: clamp(1.25rem, 2.2vw, 1.65rem);
  font-weight: 680;
  line-height: 1.3;
  letter-spacing: -.018em;
}

h4 {
  margin-bottom: 10px;
  font-size: 1.05rem;
  font-weight: 680;
}

p {
  margin-top: 0;
}

.lead {
  max-width: 710px;
  color: var(--color-muted);
  font-size: clamp(1.03rem, 1.8vw, 1.22rem);
  line-height: 1.85;
}

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

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

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

.gradient-text {
  background: linear-gradient(90deg, var(--color-text), var(--color-accent));
  background-clip: text;
  color: transparent;
  -webkit-background-clip: text;
}

.button {
  min-height: 48px;
  max-width: 100%;
  padding: 0 22px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border-radius: var(--radius-pill);
  font-size: .94rem;
  font-weight: 720;
  line-height: 1.2;
  text-align: center;
  cursor: pointer;
  transition:
    transform var(--duration-fast) var(--ease-soft),
    background-color var(--duration-fast) var(--ease-soft),
    color var(--duration-fast) var(--ease-soft);
}

.button svg {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
}

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

.button:focus-visible,
.nav-link:focus-visible,
.language-trigger:focus-visible,
.menu-toggle:focus-visible,
.footer-link:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

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

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

.button-secondary {
  background: var(--color-panel);
  color: var(--color-text);
  box-shadow: inset 0 0 0 1px var(--color-border);
}

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

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

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

.button[aria-disabled="true"],
.button:disabled {
  opacity: .46;
  pointer-events: none;
}

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

.badge {
  min-height: 31px;
  padding: 0 11px;
  background: var(--color-panel-soft);
  color: var(--color-muted);
  font-size: .76rem;
  font-weight: 620;
}

.badge::before {
  width: 6px;
  height: 6px;
  flex: 0 0 auto;
  border-radius: var(--radius-circle);
  background: var(--color-accent);
  content: "";
}

.badge-accent {
  background: var(--color-accent-soft);
  color: var(--color-text);
  box-shadow: inset 0 0 0 1px var(--color-accent-border);
}

.tag {
  min-height: 28px;
  padding: 0 10px;
  background: var(--color-panel-raised);
  color: var(--color-text-soft);
  font-family: var(--font-mono);
  font-size: .7rem;
}

.panel {
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  box-shadow: inset 0 1px 0 var(--color-border), var(--shadow-panel);
}

.panel-raised {
  background: var(--color-panel-raised);
}

.panel-pad {
  padding: clamp(22px, 4vw, 38px);
}

.tilt,
.tilt-soft {
  transform: rotate(-.35deg);
  transform-origin: center;
}

.site-header {
  position: relative;
  z-index: 50;
  height: var(--nav-height);
}

.nav-shell {
  width: min(calc(100% - 64px), var(--page-width));
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
  gap: 12px;
  margin-right: auto;
}

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

.brand-copy {
  display: flex;
  align-items: baseline;
  gap: 9px;
  white-space: nowrap;
}

.brand-en {
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 760;
  letter-spacing: -.02em;
}

.brand-local {
  color: var(--color-muted);
  font-size: .78rem;
  font-weight: 520;
  letter-spacing: .07em;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 5px;
}

.nav-link,
.more-trigger,
.language-trigger {
  min-height: 40px;
  padding: 0 13px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-muted);
  font-size: .875rem;
  font-weight: 550;
  white-space: nowrap;
  cursor: pointer;
  transition:
    color var(--duration-fast) var(--ease-soft),
    background-color var(--duration-fast) var(--ease-soft);
}

.nav-link:hover,
.more-trigger:hover,
.language-trigger:hover {
  background: var(--color-text-faint);
  color: var(--color-text);
}

.nav-link.is-active {
  color: var(--color-text);
}

.nav-link.is-active::after {
  width: 4px;
  height: 4px;
  margin-left: 7px;
  flex: 0 0 auto;
  border-radius: var(--radius-circle);
  background: var(--color-accent);
  content: "";
}

.more-menu,
.language-menu {
  position: relative;
}

.more-trigger::after,
.language-trigger::after {
  margin-left: 7px;
  color: var(--color-muted);
  content: "⌄";
  transform: translateY(-1px);
}

.more-panel,
.language-panel {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 198px;
  padding: 8px;
  visibility: hidden;
  opacity: 0;
  transform: translateY(-5px);
  border-radius: var(--radius-md);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-panel);
  transition:
    opacity var(--duration-fast) var(--ease-soft),
    transform var(--duration-fast) var(--ease-soft),
    visibility var(--duration-fast) var(--ease-soft);
}

.more-menu:hover .more-panel,
.more-menu:focus-within .more-panel,
.language-menu.is-open .language-panel {
  visibility: visible;
  opacity: 1;
  transform: translateY(0);
}

.more-panel a,
.language-panel a {
  min-height: 44px;
  padding: 0 12px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-sm);
  color: var(--color-muted);
  font-size: .875rem;
}

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

.nav-tools {
  display: flex;
  align-items: center;
  gap: 8px;
}

.login-button {
  min-height: 40px;
  padding: 0 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-pill);
  background: var(--color-panel-raised);
  color: var(--color-text);
  box-shadow: inset 0 0 0 1px var(--color-border);
  font-size: .875rem;
  font-weight: 680;
  white-space: nowrap;
  transition: background-color var(--duration-fast) var(--ease-soft);
}

.login-button:hover {
  background: var(--color-border);
}

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

.menu-toggle svg {
  width: 22px;
  height: 22px;
}

.mobile-drawer {
  display: none;
}

.nav-veil {
  display: none;
}

.site-footer {
  position: relative;
  overflow-x: clip;
  background: var(--color-panel);
  box-shadow: inset 0 1px 0 var(--color-border);
}

.footer-grid {
  padding-top: 72px;
  padding-bottom: 52px;
  display: grid;
  grid-template-columns: minmax(240px, 1.25fr) repeat(3, minmax(150px, 1fr));
  gap: 48px;
}

.footer-brand {
  max-width: 360px;
}

.footer-brand .brand {
  margin-bottom: 18px;
}

.footer-brand p {
  color: var(--color-muted);
  line-height: 1.8;
}

.footer-title {
  margin: 0 0 16px;
  color: var(--color-text);
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: .06em;
}

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

.footer-link {
  width: fit-content;
  max-width: 100%;
  color: var(--color-muted);
  font-size: .875rem;
  overflow-wrap: anywhere;
}

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

.footer-bottom {
  padding-top: 20px;
  padding-bottom: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
  font-size: .78rem;
}

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

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

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

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

.prose {
  color: var(--color-text-soft);
  font-size: 1rem;
  line-height: 1.9;
}

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

.prose h2 {
  margin-top: 3.8rem;
}

.prose h3 {
  margin-top: 2.5rem;
}

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

.prose ul,
.prose ol {
  padding-left: 1.35rem;
}

.prose li + li {
  margin-top: .65rem;
}

.prose blockquote {
  margin: 1.7rem 0;
}

body:has(.toc-tabs) section[id] {
  scroll-margin-top: calc(var(--toc-top) + var(--toc-height) + 20px);
}

@media (max-width: 1080px) {
  .nav-shell {
    width: 100%;
    padding-inline: var(--gutter);
  }

  .desktop-nav {
    display: none;
  }

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

  .menu-toggle {
    display: grid;
  }

  .mobile-drawer {
    position: absolute;
    z-index: 54;
    top: var(--nav-height);
    right: var(--gutter);
    left: var(--gutter);
    max-height: calc(100dvh - var(--nav-height) - 12px);
    padding: 10px;
    overflow-y: auto;
    overscroll-behavior: contain;
    border-radius: var(--radius-lg);
    background: var(--color-panel-raised);
    box-shadow: var(--shadow-panel);
  }

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

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

  .mobile-drawer a {
    width: 100%;
    min-height: 48px;
    padding: 11px 14px;
    display: flex;
    align-items: center;
    border-radius: var(--radius-sm);
    color: var(--color-muted);
  }

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

  .mobile-language-title {
    margin: 12px 14px 5px;
    color: var(--color-muted);
    font-family: var(--font-mono);
    font-size: .68rem;
    letter-spacing: .1em;
  }

  .nav-veil {
    position: fixed;
    z-index: 49;
    inset: var(--nav-height) 0 0;
    background: var(--color-overlay);
  }

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

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

@media (max-width: 640px) {
  :root {
    --gutter: 18px;
    --nav-height: 72px;
    --section-space: 78px;
    --toc-top: 8px;
  }

  .brand-copy {
    gap: 6px;
  }

  .brand-en {
    font-size: 1.04rem;
  }

  .brand-local {
    display: none;
  }

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

  .nav-tools {
    margin-left: auto;
    gap: 6px;
  }

  .nav-tools .language-menu {
    display: none;
  }

  .login-button {
    min-height: 40px;
    padding-inline: 15px;
  }

  h1 {
    font-size: clamp(2.65rem, 13vw, 3.65rem);
  }

  h2 {
    font-size: clamp(1.85rem, 9vw, 2.6rem);
  }

  .button {
    min-height: 50px;
  }

  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 34px;
  }

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

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

  .panel-pad {
    padding: 22px;
  }

  pre {
    padding: 16px;
  }
}

@media (max-width: 390px) {
  :root {
    --gutter: 16px;
  }

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

  .nav-shell {
    gap: 10px;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: .01ms !important;
  }

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