:root {
  --color-bg: #10203F;
  --color-panel: #172A55;
  --color-panel-raised: #1F366B;
  --color-border: #31497F;
  --color-accent: #A06BFF;
  --color-accent-strong: #7C48E0;
  --color-accent-pink: #FF7FD1;
  --color-text: #EEF1FB;
  --color-text-muted: #A9B5D8;
  --color-success: #4ADE9C;
  --color-warning: #FFC466;
  --color-error: #FF6B7A;
  --color-shadow: #060D20;
  --color-focus: #FFC466;
  --color-overlay: #0B1732;
  --color-white: #FFFFFF;
  --font-display: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Hiragino Sans', 'Yu Gothic', 'Malgun Gothic', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-pill: 999px;
  --header-height: 64px;
  --content-width: 1240px;
  --reading-width: 780px;
  --gutter: 32px;
  --section-space: 104px;
  --shadow-panel: 0 34px 70px color-mix(in srgb, var(--color-shadow) 62%, transparent);
  --shadow-action: 0 12px 34px color-mix(in srgb, var(--color-accent) 36%, transparent);
  --transition-fast: 180ms ease;
  --transition-reveal: 620ms cubic-bezier(.22, 1, .36, 1);
  --toc-offset: 84px;
}

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

html {
  margin: 0;
  padding: 0;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
  background: var(--color-bg);
}

html.nav-open {
  overflow: hidden;
}

body {
  margin: 0;
  min-width: 0;
  overflow-x: clip;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

svg {
  max-width: 100%;
}

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

button,
summary,
select {
  cursor: pointer;
}

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

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

ul[role='list'],
ol[role='list'],
.list-reset {
  margin: 0;
  padding: 0;
  list-style: none;
}

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

h1 {
  margin: 0 0 24px;
  font-size: clamp(52px, 5.2vw, 72px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

h2 {
  margin: 0 0 22px;
  font-size: clamp(34px, 4vw, 52px);
  font-weight: 800;
  letter-spacing: -0.015em;
  line-height: 1.16;
}

h3 {
  margin: 0 0 14px;
  font-size: clamp(21px, 2.3vw, 28px);
  font-weight: 750;
  line-height: 1.28;
}

h4 {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
}

p:last-child,
ul:last-child,
ol:last-child,
blockquote:last-child {
  margin-bottom: 0;
}

strong {
  color: var(--color-text);
  font-weight: 650;
}

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

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

:not(pre) > code {
  padding: 0.14em 0.42em;
  overflow-wrap: anywhere;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  color: var(--color-text);
  font-size: 0.9em;
}

pre {
  max-width: 100%;
  margin: 24px 0;
  padding: 20px;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-overlay);
  color: var(--color-text);
  tab-size: 2;
  -webkit-overflow-scrolling: touch;
}

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

hr {
  height: 1px;
  margin: 48px 0;
  border: 0;
  background: var(--color-border);
}

::selection {
  background: color-mix(in srgb, var(--color-accent) 46%, transparent);
  color: var(--color-text);
}

:where(a, button, input, select, textarea, summary, [role='tab']):focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

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

@media (max-width: 640px) {
  .no-break {
    white-space: normal;
  }
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.grad-text {
  background: linear-gradient(92deg, var(--color-accent) 8%, var(--color-accent-pink) 92%);
  background-clip: text;
  color: transparent;
  -webkit-background-clip: text;
}

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

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

.section-tint {
  border-block: 1px solid color-mix(in srgb, var(--color-border) 58%, transparent);
  background: color-mix(in srgb, var(--color-panel) 42%, transparent);
}

.section-head {
  max-width: 760px;
  margin-bottom: 44px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-height: 28px;
  margin-bottom: 14px;
  color: var(--color-accent-pink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 7px;
  height: 7px;
  flex-shrink: 0;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
  box-shadow: 0 0 12px color-mix(in srgb, var(--color-accent) 72%, transparent);
  content: '';
}

.lede {
  max-width: 42em;
  margin: 0;
  color: var(--color-text-muted);
  font-size: clamp(16px, 1.7vw, 19px);
  line-height: 1.85;
}

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

.btn,
.btn-primary,
.btn-secondary,
.btn-quiet {
  display: inline-flex;
  min-width: 24px;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 11px 25px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-weight: 700;
  line-height: 1.25;
  text-align: center;
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast),
    background-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

.btn-primary {
  border-color: color-mix(in srgb, var(--color-accent-pink) 45%, transparent);
  background: linear-gradient(120deg, var(--color-accent-strong), var(--color-accent));
  box-shadow: var(--shadow-action);
  color: var(--color-text);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 16px 40px color-mix(in srgb, var(--color-accent) 46%, transparent);
}

.btn-secondary {
  border-color: var(--color-border);
  background: color-mix(in srgb, var(--color-panel) 68%, transparent);
  color: var(--color-text);
}

.btn-secondary:hover {
  border-color: var(--color-accent);
  background: color-mix(in srgb, var(--color-accent) 13%, var(--color-panel));
}

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

.btn-quiet:hover {
  color: var(--color-text);
  background: var(--color-panel);
}

.btn[aria-disabled='true'],
.btn:disabled,
.btn-primary:disabled,
.btn-secondary:disabled {
  cursor: not-allowed;
  opacity: 0.52;
  transform: none;
  box-shadow: none;
}

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

.panel,
.card {
  min-width: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-panel);
  box-shadow: inset 0 1px 0 color-mix(in srgb, var(--color-text) 7%, transparent);
}

.panel {
  padding: clamp(24px, 4vw, 42px);
}

.card {
  padding: 24px;
}

.badge,
.fact-pill,
.tag {
  display: inline-flex;
  max-width: 100%;
  min-height: 28px;
  align-items: center;
  gap: 7px;
  padding: 4px 11px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-panel-raised) 72%, transparent);
  color: var(--color-text-muted);
  font-size: 12px;
  line-height: 1.45;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.badge-accent {
  border-color: color-mix(in srgb, var(--color-accent) 62%, var(--color-border));
  background: color-mix(in srgb, var(--color-accent) 15%, transparent);
  color: var(--color-accent-pink);
}

.badge-success {
  border-color: color-mix(in srgb, var(--color-success) 55%, var(--color-border));
  color: var(--color-success);
}

.status-dot {
  width: 8px;
  height: 8px;
  flex-shrink: 0;
  border-radius: var(--radius-pill);
  background: var(--color-success);
  box-shadow: 0 0 10px color-mix(in srgb, var(--color-success) 60%, transparent);
}

.site-head {
  position: relative;
  z-index: 50;
  border-bottom: 1px solid color-mix(in srgb, var(--color-border) 45%, transparent);
  background: color-mix(in srgb, var(--color-bg) 90%, transparent);
}

.head-in {
  position: relative;
  display: flex;
  height: var(--header-height);
  align-items: center;
  gap: 24px;
}

.brand {
  display: inline-flex;
  min-height: 44px;
  flex-shrink: 0;
  align-items: center;
  gap: 10px;
}

.brand-logo {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  border-radius: 8px;
}

.brand-copy {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  white-space: nowrap;
}

.brand-name {
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.brand-local {
  color: var(--color-text-muted);
  font-size: 13px;
  font-weight: 500;
}

.main-nav {
  display: flex;
  min-width: 0;
  align-items: center;
  gap: 2px;
  margin-inline: auto;
}

.main-nav a {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  justify-content: center;
  padding: 7px 12px;
  border-radius: var(--radius-pill);
  color: var(--color-text-muted);
  font-size: 13px;
  white-space: nowrap;
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast);
}

.main-nav a:hover {
  color: var(--color-text);
}

.main-nav a.active {
  background: color-mix(in srgb, var(--color-accent) 20%, transparent);
  color: var(--color-text);
  font-weight: 650;
}

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

.lang-menu {
  position: relative;
}

.lang-trigger {
  display: inline-flex;
  min-width: 44px;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 6px 8px;
  border: 0;
  background: transparent;
  color: var(--color-text-muted);
  font-size: 13px;
}

.lang-popover {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  display: none;
  width: 164px;
  padding: 8px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-panel);
}

.lang-menu.is-open .lang-popover {
  display: block;
}

.lang-popover a {
  display: flex;
  min-height: 40px;
  align-items: center;
  padding: 8px 11px;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
}

.lang-popover a:hover,
.lang-popover a[aria-current='true'] {
  background: color-mix(in srgb, var(--color-accent) 16%, transparent);
  color: var(--color-text);
}

.btn-login {
  display: inline-flex;
  min-width: 68px;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding: 8px 18px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-panel) 74%, transparent);
  font-size: 14px;
  font-weight: 650;
}

.btn-login:hover {
  border-color: var(--color-accent);
  background: color-mix(in srgb, var(--color-accent) 14%, transparent);
}

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

.nav-toggle-lines,
.nav-toggle-lines::before,
.nav-toggle-lines::after {
  display: block;
  width: 18px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--color-text);
  content: '';
  transition: transform var(--transition-fast);
}

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

.nav-toggle-lines::before {
  position: absolute;
  top: -6px;
}

.nav-toggle-lines::after {
  position: absolute;
  top: 6px;
}

.nav-toggle[aria-expanded='true'] .nav-toggle-lines {
  background: transparent;
}

.nav-toggle[aria-expanded='true'] .nav-toggle-lines::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded='true'] .nav-toggle-lines::after {
  top: 0;
  transform: rotate(-45deg);
}

.mobile-nav {
  position: absolute;
  z-index: 54;
  top: var(--header-height);
  right: 0;
  left: 0;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  padding: 12px var(--gutter) 22px;
  overflow-y: auto;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-panel-raised);
  overscroll-behavior: contain;
}

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

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 46px;
  align-items: center;
  padding: 10px 13px;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
}

.mobile-nav a:hover,
.mobile-nav a.active {
  background: color-mix(in srgb, var(--color-accent) 18%, transparent);
  color: var(--color-text);
}

.mobile-nav-languages {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--color-border);
}

.nav-veil {
  position: fixed;
  z-index: 45;
  inset: var(--header-height) 0 0;
  display: none;
  border: 0;
  background: color-mix(in srgb, var(--color-overlay) 70%, transparent);
}

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

.site-footer {
  overflow-x: clip;
  border-top: 1px solid var(--color-border);
  background: color-mix(in srgb, var(--color-panel) 54%, var(--color-bg));
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(220px, 1.2fr) minmax(0, 2fr);
  gap: 60px;
  padding-top: 66px;
  padding-bottom: 54px;
}

.footer-brand {
  min-width: 0;
}

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

.footer-brand p {
  max-width: 34em;
  color: var(--color-text-muted);
}

.footer-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 34px;
}

.footer-title {
  margin-bottom: 14px;
  color: var(--color-text);
  font-size: 14px;
  font-weight: 700;
}

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

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

.footer-links a {
  display: inline-flex;
  min-height: 28px;
  align-items: center;
  color: var(--color-text-muted);
  font-size: 13px;
}

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

.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 color-mix(in srgb, var(--color-border) 68%, transparent);
  color: var(--color-text-muted);
  font-size: 12px;
}

.footer-legal,
.footer-languages {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
}

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

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

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

.prose {
  min-width: 0;
  color: var(--color-text-muted);
  font-size: 16px;
}

.prose h2 {
  margin-top: 72px;
  color: var(--color-text);
}

.prose h3 {
  margin-top: 42px;
  color: var(--color-text);
}

.prose p,
.prose li {
  overflow-wrap: break-word;
}

.prose a {
  color: var(--color-accent-pink);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--color-accent-pink) 48%, transparent);
  text-underline-offset: 3px;
}

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

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

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

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

@media (max-width: 1160px) {
  .main-nav {
    display: none;
  }

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

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

@media (max-width: 800px) {
  :root {
    --gutter: 20px;
    --section-space: 76px;
  }

  h1 {
    font-size: clamp(34px, 9.5vw, 40px);
    line-height: 1.12;
  }

  h2 {
    font-size: clamp(29px, 8vw, 38px);
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 40px;
  }

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

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

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
    --section-space: 64px;
  }

  body {
    font-size: 14px;
  }

  .brand-local,
  .lang-trigger-label {
    display: none;
  }

  .head-in {
    gap: 8px;
  }

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

  .btn-login {
    min-width: 60px;
    padding-inline: 13px;
  }

  .mobile-nav {
    padding-inline: var(--gutter);
  }

  .button-row > :where(.btn, .btn-primary, .btn-secondary) {
    flex: 1 1 140px;
  }

  .panel,
  .card {
    border-radius: var(--radius-lg);
  }

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

  .tilt,
  .tilt-card {
    transform: none;
  }
}

@media (max-width: 360px) {
  .brand-name {
    font-size: 16px;
  }

  .btn-login {
    min-width: 54px;
    padding-inline: 10px;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-duration: 0s;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

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