:root {
  --color-bg: #262B96;
  --color-bg-deep: #1F2378;
  --color-panel: #2F35A8;
  --color-panel-raised: #383FBA;
  --color-panel-alt: #3D44BF;
  --color-border: #4A51C4;
  --color-accent: #FF8A3D;
  --color-accent-dark: #E86F1F;
  --color-coral: #FF5C6A;
  --color-lime: #B8E84A;
  --color-pink: #E86BD8;
  --color-warning: #FFC94D;
  --color-text: #FFFFFF;
  --color-text-muted: #C3C7F2;
  --color-ink: #23276B;
  --color-flag-red: #E8404F;
  --color-flag-blue: #2C4699;
  --color-transparent: transparent;
  --color-overlay: rgba(31, 35, 120, 0.94);
  --color-header: rgba(31, 35, 120, 0.86);
  --color-panel-glass: rgba(56, 63, 186, 0.45);
  --color-band: rgba(47, 53, 168, 0.62);
  --color-border-soft: rgba(74, 81, 196, 0.58);
  --color-text-soft: rgba(195, 199, 242, 0.68);
  --color-star: rgba(255, 255, 255, 0.48);
  --color-star-soft: rgba(195, 199, 242, 0.28);
  --color-accent-glow: rgba(255, 138, 61, 0.48);
  --color-coral-glow: rgba(255, 92, 106, 0.48);
  --color-lime-glow: rgba(184, 232, 74, 0.42);
  --color-pink-glow: rgba(232, 107, 216, 0.46);
  --color-nebula: rgba(88, 97, 230, 0.31);
  --color-nebula-pink: rgba(232, 107, 216, 0.13);
  --color-nebula-orange: rgba(255, 138, 61, 0.08);
  --color-shadow: rgba(10, 13, 60, 0.5);
  --color-shadow-soft: rgba(13, 16, 74, 0.4);
  --color-focus: rgba(255, 201, 77, 0.72);
  --color-table-stripe: rgba(56, 63, 186, 0.38);
  --color-table-hover: rgba(74, 81, 196, 0.56);
  --color-success-tint: rgba(184, 232, 74, 0.12);
  --color-warning-tint: rgba(255, 201, 77, 0.12);
  --color-error-tint: rgba(255, 92, 106, 0.12);
  --gradient-page: linear-gradient(180deg, var(--color-bg-deep) 0%, var(--color-bg) 42%, var(--color-bg) 100%);
  --gradient-accent: linear-gradient(180deg, var(--color-accent), var(--color-accent-dark));
  --gradient-title: linear-gradient(94deg, var(--color-accent) 12%, var(--color-pink) 92%);
  --gradient-logo: linear-gradient(135deg, var(--color-accent), var(--color-pink));
  --font-display: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', -apple-system, 'PingFang SC', 'Hiragino Sans', 'Malgun Gothic', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'Noto Sans JP', 'Noto Sans KR', -apple-system, 'PingFang SC', 'Hiragino Sans', 'Malgun Gothic', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  --radius-xl: 44px;
  --radius-lg: 24px;
  --radius-md: 12px;
  --radius-sm: 6px;
  --radius-pill: 999px;
  --shadow-card: 0 16px 30px var(--color-shadow);
  --shadow-button: 0 12px 26px var(--color-accent-glow);
  --shadow-soft: 0 10px 24px var(--color-shadow-soft);
  --header-height: 64px;
  --content-width: 1360px;
  --reading-width: 56rem;
  --gutter: clamp(16px, 3vw, 32px);
  --section-gap: clamp(72px, 9vw, 132px);
  --toc-offset: 76px;
  --transition-fast: 180ms ease;
  --transition-reveal: 580ms cubic-bezier(0.2, 0.7, 0.2, 1);
}

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

html {
  min-width: 320px;
  scroll-behavior: smooth;
  background: var(--color-bg-deep);
}

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 320px;
  min-height: 100%;
  margin: 0;
  overflow-x: clip;
  color: var(--color-text);
  background: var(--gradient-page);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

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

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

button {
  border: 0;
}

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

p,
h1,
h2,
h3,
h4,
ul,
ol,
dl,
dd,
figure,
blockquote {
  margin-top: 0;
}

ul,
ol {
  padding-left: 1.25rem;
}

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

:not(pre) > code {
  overflow-wrap: anywhere;
  padding: 0.12em 0.38em;
  border: 1px solid var(--color-border-soft);
  border-radius: var(--radius-sm);
  color: var(--color-warning);
  background: var(--color-panel-glass);
}

pre {
  max-width: 100%;
  margin: 1.5rem 0;
  overflow-x: auto;
  padding: 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg-deep);
  box-shadow: var(--shadow-soft);
  -webkit-overflow-scrolling: touch;
}

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

table {
  border-collapse: collapse;
}

::selection {
  color: var(--color-ink);
  background: var(--color-lime);
}

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

.wrap {
  width: 100%;
  max-width: var(--content-width);
  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-space {
  padding-top: var(--section-gap);
  padding-bottom: var(--section-gap);
}

.prose {
  max-width: var(--reading-width);
  margin-inline: auto;
}

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

.prose h2 {
  margin-top: 2.7rem;
  margin-bottom: 1rem;
  font-size: clamp(1.65rem, 3vw, 2.35rem);
}

.prose h3 {
  margin-top: 2rem;
  margin-bottom: 0.8rem;
  font-size: clamp(1.25rem, 2.4vw, 1.6rem);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  max-width: 100%;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: 2px;
  background: var(--color-accent);
  content: "";
}

h1,
h2,
h3,
h4 {
  color: var(--color-text);
  font-family: var(--font-display);
  font-weight: 850;
  line-height: 1.16;
  text-wrap: balance;
}

h1,
.hero-title {
  font-size: clamp(52px, 5.2vw, 72px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.01em;
}

h2 {
  font-size: clamp(2rem, 4vw, 3.35rem);
}

h3 {
  font-size: clamp(1.3rem, 2.4vw, 1.8rem);
}

.no-break {
  white-space: nowrap;
}

.text-gradient {
  color: var(--color-accent);
  background: var(--gradient-title);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: var(--color-transparent);
}

.lead {
  max-width: 44rem;
  color: var(--color-text-muted);
  font-size: clamp(1rem, 1.5vw, 1.2rem);
  line-height: 1.75;
}

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

.panel {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-panel);
  box-shadow: var(--shadow-soft);
}

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

.card {
  position: relative;
  min-width: 0;
  padding: clamp(22px, 4vw, 38px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  box-shadow: var(--shadow-soft);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
}

.badge,
.tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: 100%;
  padding: 7px 14px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  color: var(--color-text-muted);
  background: var(--color-panel-glass);
  font-size: 0.78rem;
  font-weight: 700;
  line-height: 1.3;
}

.badge-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 2px;
  background: var(--color-accent);
}

.badge-success .badge-dot {
  background: var(--color-lime);
}

.badge-pink .badge-dot {
  background: var(--color-pink);
}

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

.btn {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 12px 28px;
  border: 1px solid var(--color-transparent);
  border-radius: var(--radius-pill);
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 0.98rem;
  font-weight: 800;
  line-height: 1.2;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-fast);
}

.btn svg {
  width: 17px;
  height: 17px;
  flex: 0 0 auto;
}

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

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

.btn-secondary {
  border-color: var(--color-border);
  color: var(--color-text);
  background: var(--color-panel-glass);
}

.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-soft);
}

.btn-light {
  color: var(--color-ink);
  background: var(--color-text);
  box-shadow: var(--shadow-soft);
}

.btn:disabled,
.btn.is-disabled {
  cursor: not-allowed;
  opacity: 0.58;
  transform: none;
}

.site-header {
  position: relative;
  z-index: 40;
  height: var(--header-height);
  border-bottom: 1px solid var(--color-border-soft);
  background: var(--color-header);
}

.header-inner {
  position: relative;
  display: flex;
  width: 100%;
  max-width: var(--content-width);
  height: 100%;
  align-items: center;
  gap: 24px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.site-brand {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
}

.site-brand img {
  width: 34px;
  height: 34px;
  flex: 0 0 auto;
}

.brand-word {
  color: var(--color-text);
  font-size: 1.18rem;
  font-weight: 850;
  letter-spacing: 0.02em;
}

.brand-local {
  color: var(--color-text-muted);
  font-size: 0.82rem;
  font-weight: 650;
}

.desktop-nav {
  display: flex;
  min-width: 0;
  flex: 1 1 auto;
  align-items: center;
  gap: 2px;
}

.desktop-nav a {
  position: relative;
  display: flex;
  min-height: var(--header-height);
  align-items: center;
  padding-inline: 9px;
  color: var(--color-text-muted);
  font-size: 0.82rem;
  font-weight: 650;
  white-space: nowrap;
  transition: color var(--transition-fast);
}

.desktop-nav a::after {
  position: absolute;
  right: 9px;
  bottom: 0;
  left: 9px;
  height: 3px;
  border-radius: var(--radius-sm);
  background: var(--gradient-title);
  content: "";
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-fast);
}

.desktop-nav a:hover,
.desktop-nav a.is-active {
  color: var(--color-text);
}

.desktop-nav a:hover::after,
.desktop-nav a.is-active::after {
  transform: scaleX(1);
}

.header-tools {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 10px;
}

.login-link {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding-inline: 21px;
  border-radius: var(--radius-pill);
  color: var(--color-ink);
  background: var(--color-text);
  font-size: 0.84rem;
  font-weight: 800;
  box-shadow: var(--shadow-soft);
}

.language-picker {
  position: relative;
}

.language-button {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  gap: 6px;
  padding-inline: 8px;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  background: var(--color-transparent);
  cursor: pointer;
  font-size: 0.78rem;
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 60;
  display: none;
  width: 170px;
  padding: 8px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  box-shadow: var(--shadow-card);
}

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

.language-menu a {
  display: flex;
  min-height: 42px;
  align-items: center;
  padding-inline: 12px;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: 0.84rem;
}

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

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

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

.mobile-nav {
  position: absolute;
  top: var(--header-height);
  right: 0;
  left: 0;
  z-index: 55;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  padding: 10px var(--gutter) 22px;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg-deep);
  box-shadow: var(--shadow-card);
  overscroll-behavior: contain;
}

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

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

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 48px;
  align-items: center;
  padding: 11px 12px;
  border-bottom: 1px solid var(--color-border-soft);
  color: var(--color-text-muted);
  font-weight: 700;
}

.mobile-nav a.is-active,
.mobile-nav a:hover {
  color: var(--color-text);
}

.mobile-language-title {
  margin: 18px 12px 6px;
  color: var(--color-text-soft);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
}

.mobile-language-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.nav-veil {
  position: fixed;
  inset: var(--header-height) 0 0;
  z-index: 35;
  display: none;
  background: var(--color-overlay);
}

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

.site-footer {
  position: relative;
  z-index: 2;
  margin-top: var(--section-gap);
  border-top: 1px solid var(--color-border);
  background: var(--color-bg-deep);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr 0.85fr;
  gap: clamp(28px, 5vw, 70px);
  padding-top: 64px;
  padding-bottom: 48px;
}

.footer-brand p {
  max-width: 24rem;
  margin-top: 18px;
  color: var(--color-text-muted);
}

.footer-heading {
  margin-bottom: 14px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.1em;
}

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

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

.footer-links a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

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

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding-top: 20px;
  padding-bottom: 24px;
  border-top: 1px solid var(--color-border-soft);
  color: var(--color-text-muted);
  font-size: 0.82rem;
}

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

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

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

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

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

.decorated-section,
.hero-atmosphere {
  position: relative;
  overflow-x: clip;
}

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

@media (max-width: 1500px) {
  .brand-local {
    display: none;
  }
}

@media (max-width: 1180px) {
  .desktop-nav a {
    padding-inline: 6px;
    font-size: 0.75rem;
  }

  .desktop-nav a::after {
    right: 6px;
    left: 6px;
  }

  .language-button {
    display: none;
  }
}

@media (max-width: 980px) {
  .desktop-nav {
    display: none;
  }

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

  .menu-toggle {
    display: grid;
  }

  .language-picker {
    display: none;
  }

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

@media (max-width: 768px) {
  h1,
  .hero-title {
    font-size: clamp(28px, 9.7vw, 40px);
    line-height: 1.14;
    letter-spacing: -0.01em;
  }

  .section-space {
    padding-top: 64px;
    padding-bottom: 64px;
  }

  .brand-local {
    display: none;
  }

  .login-link {
    min-height: 38px;
    padding-inline: 16px;
  }
}

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
    --radius-xl: 28px;
    --radius-lg: 20px;
  }

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

  .tilt {
    transform: none;
  }

  .button-row {
    width: 100%;
  }

  .button-row .btn {
    flex: 1 1 150px;
  }

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

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

  .mobile-language-links {
    grid-template-columns: 1fr;
  }
}

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

  .site-brand img {
    width: 30px;
    height: 30px;
  }

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

  .header-inner {
    gap: 7px;
  }

  .login-link {
    padding-inline: 12px;
    font-size: 0.78rem;
  }
}

@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;
  }

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