:root {
  --color-page: #FDFDFC;
  --color-surface: #FFFFFF;
  --color-panel: #F5F5F3;
  --color-mint: #EDF4E4;
  --color-apricot: #FBF0DB;
  --color-mist: #E6EFF8;
  --color-border: #E6E6E1;
  --color-grid: #ECECE8;
  --color-chrome: #D9D9D4;
  --color-accent: #5B8C2A;
  --color-accent-dark: #3F6A1C;
  --color-accent-soft: rgba(91, 140, 42, 0.14);
  --color-accent-shadow: rgba(91, 140, 42, 0.45);
  --color-text: #1C2117;
  --color-muted: #5F665A;
  --color-on-accent: #FFFFFF;
  --color-success: #4A9A5B;
  --color-warning: #D99A2B;
  --color-error: #D14B47;
  --color-shadow-soft: rgba(28, 33, 23, 0.04);
  --color-shadow-card: rgba(28, 33, 23, 0.08);
  --color-shadow-panel: rgba(28, 33, 23, 0.18);
  --color-shadow-segment: rgba(63, 106, 28, 0.28);
  --color-veil: rgba(28, 33, 23, 0.28);

  --font-display: 'Inter', 'Noto Sans SC', system-ui, -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', system-ui, -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, 'Liberation Mono', monospace;

  --radius-pill: 999px;
  --radius-panel: 24px;
  --radius-card: 14px;
  --radius-control: 10px;
  --radius-small: 8px;

  --shadow-card: 0 12px 32px var(--color-shadow-card), 0 1px 2px var(--color-shadow-soft);
  --shadow-panel: 0 24px 48px -28px var(--color-shadow-panel);
  --shadow-accent: 0 10px 22px -8px var(--color-accent-shadow);
  --shadow-segment: 0 2px 6px var(--color-shadow-segment);

  --header-height: 72px;
  --content-width: 1120px;
  --header-width: 1280px;
  --reading-width: 760px;
  --gutter: 32px;
  --section-space: 104px;
  --transition-fast: 180ms ease;
  --transition-reveal: 620ms cubic-bezier(0.2, 0.7, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 320px;
  margin: 0;
  overflow-x: clip;
  background: var(--color-page);
  color: var(--color-text);
  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%;
}

img {
  height: auto;
}

svg[aria-hidden="true"] {
  flex-shrink: 0;
}

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

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

button {
  border: 0;
}

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

h1,
h2,
h3,
h4 {
  margin-bottom: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.18;
  text-wrap: balance;
}

h1 {
  font-size: clamp(34px, 4vw, 48px);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(28px, 3vw, 38px);
  letter-spacing: -0.018em;
}

h3 {
  font-size: clamp(21px, 2vw, 27px);
  letter-spacing: -0.012em;
}

h4 {
  font-size: 18px;
}

p {
  margin-bottom: 1em;
}

strong {
  font-weight: 700;
}

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

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

:not(pre) > code {
  padding: 0.12em 0.38em;
  overflow-wrap: anywhere;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-small);
  background: var(--color-panel);
  color: var(--color-text);
  font-size: 0.9em;
}

pre {
  max-width: 100%;
  margin-bottom: 24px;
  padding: 20px;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background: var(--color-panel);
  color: var(--color-text);
  line-height: 1.75;
  -webkit-overflow-scrolling: touch;
}

pre code {
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  white-space: pre;
}

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

th,
td {
  text-align: left;
}

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

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

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 1000;
  padding: 10px 16px;
  border-radius: var(--radius-pill);
  background: var(--color-accent-dark);
  color: var(--color-on-accent);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.wrap {
  width: 100%;
  max-width: calc(var(--content-width) + var(--gutter) * 2);
  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);
}

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

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

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

.section-head {
  max-width: 720px;
  margin-bottom: 42px;
}

.section-head.centered {
  margin-inline: auto;
  text-align: center;
}

.section-kicker {
  margin-bottom: 10px;
  color: var(--color-accent-dark);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.section-lead {
  margin-top: 14px;
  margin-bottom: 0;
  color: var(--color-muted);
  font-size: 18px;
}

.nowrap-term {
  white-space: nowrap;
}

.surface-card {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background: var(--color-surface);
  color: var(--color-text);
  box-shadow: var(--shadow-card);
}

.soft-panel {
  padding: clamp(24px, 5vw, 56px);
  border-radius: var(--radius-panel);
  background: var(--color-panel);
  color: var(--color-text);
  box-shadow: var(--shadow-panel);
}

.soft-panel--mint {
  background: var(--color-mint);
  color: var(--color-text);
}

.soft-panel--apricot {
  background: var(--color-apricot);
  color: var(--color-text);
}

.soft-panel--mist {
  background: var(--color-mist);
  color: var(--color-text);
}

.tilt-left {
  transform: rotate(-1.5deg);
}

.tilt-right {
  transform: rotate(1.5deg);
}

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

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

.text-link {
  color: var(--color-accent-dark);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: var(--color-accent-soft);
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

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

.button,
.btn {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 28px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  cursor: pointer;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.2;
  text-align: center;
  transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast), transform var(--transition-fast);
}

.button svg,
.btn svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.button:hover,
.btn:hover {
  transform: translateY(-1px);
}

.button.button--primary,
.btn.btn-primary {
  background: var(--color-accent-dark);
  color: var(--color-on-accent);
  box-shadow: var(--shadow-accent);
}

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

.button--secondary,
.btn-ghost {
  border-color: var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
}

.button--secondary:hover,
.btn-ghost:hover {
  border-color: var(--color-muted);
  background: var(--color-surface);
  color: var(--color-text);
}

.button--soft {
  border-color: var(--color-accent-soft);
  background: var(--color-mint);
  color: var(--color-accent-dark);
}

.button[disabled],
.button.is-disabled,
.btn[disabled] {
  cursor: not-allowed;
  opacity: 0.58;
  transform: none;
  box-shadow: none;
}

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

.badge,
.fact-chip,
.platform-chip {
  max-width: 100%;
}

.badge {
  display: inline-flex;
  min-height: 30px;
  align-items: center;
  gap: 8px;
  padding: 5px 11px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-muted);
  font-size: 13px;
  font-weight: 650;
}

.badge-dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
}

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

.badge--warning {
  border-color: var(--color-warning);
  background: var(--color-surface);
  color: var(--color-text);
}

.badge--error {
  border-color: var(--color-error);
  background: var(--color-surface);
  color: var(--color-text);
}

.fact-chip {
  display: inline-flex;
  align-items: center;
  padding: 5px 10px;
  overflow: hidden;
  border-radius: var(--radius-small);
  background: var(--color-panel);
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: 12.5px;
}

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

.site-header {
  position: relative;
  z-index: 100;
  height: var(--header-height);
  background: var(--color-page);
  color: var(--color-text);
}

.site-header__inner {
  display: flex;
  height: var(--header-height);
  align-items: center;
  gap: 24px;
}

.site-brand {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.site-brand img {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

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

.desktop-nav__list {
  display: flex;
  align-items: center;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.desktop-nav a {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  color: var(--color-muted);
  font-size: 15px;
  font-weight: 550;
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

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

.desktop-nav a[aria-current="page"] {
  background: var(--color-mint);
  color: var(--color-accent-dark);
  font-weight: 700;
}

.header-tools {
  position: relative;
  display: flex;
  flex-shrink: 0;
  align-items: center;
  gap: 8px;
}

.language-button,
.menu-button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
}

.language-button {
  gap: 6px;
  min-width: 112px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 600;
}

.language-button__short {
  display: none;
}

.language-button__caret {
  color: var(--color-muted);
  font-size: 11px;
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 130;
  width: 176px;
  padding: 8px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background: var(--color-surface);
  color: var(--color-text);
  box-shadow: var(--shadow-card);
}

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

.language-menu a {
  display: flex;
  min-height: 42px;
  align-items: center;
  width: 100%;
  padding: 8px 12px;
  border-radius: var(--radius-small);
  color: var(--color-muted);
  font-size: 14px;
}

.language-menu a:hover,
.language-menu a[aria-current="true"] {
  background: var(--color-mint);
  color: var(--color-accent-dark);
}

.menu-button {
  display: none;
  min-width: 44px;
  padding: 0;
  border-radius: var(--radius-pill);
}

.menu-button__icon,
.menu-button__icon::before,
.menu-button__icon::after {
  width: 18px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--color-text);
}

.menu-button__icon {
  position: relative;
}

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

.menu-button__icon::before {
  top: -6px;
}

.menu-button__icon::after {
  top: 6px;
}

.menu-button[aria-expanded="true"] .menu-button__icon {
  background: transparent;
}

.menu-button[aria-expanded="true"] .menu-button__icon::before {
  top: 0;
  transform: rotate(45deg);
}

.menu-button[aria-expanded="true"] .menu-button__icon::after {
  top: 0;
  transform: rotate(-45deg);
}

.mobile-drawer {
  display: none;
}

.mobile-drawer[hidden] {
  display: none;
}

.mobile-veil {
  display: none;
}

.site-footer {
  margin-top: 80px;
  border-top: 1px solid var(--color-border);
  background: var(--color-panel);
  color: var(--color-text);
}

.site-footer__main {
  display: grid;
  grid-template-columns: minmax(240px, 1.25fr) repeat(3, minmax(150px, 0.75fr));
  gap: 48px;
  padding-top: 64px;
  padding-bottom: 48px;
}

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

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

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

.footer-column h2 {
  margin-bottom: 14px;
  font-size: 14px;
  letter-spacing: 0.04em;
}

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

.footer-links li + li,
.footer-languages li + li {
  margin-top: 7px;
}

.footer-links a,
.footer-languages a {
  color: var(--color-muted);
  font-size: 14px;
}

.footer-links a:hover,
.footer-languages a:hover,
.footer-keywords a:hover {
  color: var(--color-accent-dark);
}

.footer-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
}

.footer-keywords a {
  display: inline-flex;
  min-height: 30px;
  align-items: center;
  padding: 4px 9px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-muted);
  font-size: 12px;
}

.site-footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding-top: 20px;
  padding-bottom: 28px;
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
  font-size: 13px;
}

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

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--transition-reveal), transform var(--transition-reveal);
}

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

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

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

.prose h2 {
  margin-top: 2.2em;
  margin-bottom: 0.7em;
  scroll-margin-top: 24px;
}

.prose h3 {
  margin-top: 1.7em;
  margin-bottom: 0.65em;
  scroll-margin-top: 24px;
}

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

.prose a {
  color: var(--color-accent-dark);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

.prose li + li {
  margin-top: 0.45em;
}

.table-scroll {
  max-width: 100%;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  min-width: 680px;
  background: var(--color-surface);
  color: var(--color-text);
}

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

.data-table th {
  background: var(--color-panel);
  color: var(--color-text);
  font-size: 14px;
}

.data-table td {
  color: var(--color-muted);
}

.data-table tr:last-child td {
  border-bottom: 0;
}

@media (max-width: 960px) {
  :root {
    --section-space: 84px;
  }

  .desktop-nav {
    display: none;
  }

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

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

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

  .mobile-veil[hidden] {
    display: none;
  }

  .mobile-drawer {
    position: fixed;
    inset: var(--header-height) 0 auto;
    z-index: 110;
    display: block;
    max-height: calc(100dvh - var(--header-height));
    overflow-y: auto;
    overscroll-behavior: contain;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-surface);
    color: var(--color-text);
    box-shadow: var(--shadow-card);
  }

  .mobile-drawer__inner {
    padding: 14px var(--gutter) 24px;
  }

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

  .mobile-drawer a {
    display: flex;
    min-height: 48px;
    align-items: center;
    width: 100%;
    padding: 10px 12px;
    border-radius: var(--radius-small);
    color: var(--color-text);
  }

  .mobile-drawer a[aria-current="page"],
  .mobile-drawer a[aria-current="true"] {
    background: var(--color-mint);
    color: var(--color-accent-dark);
    font-weight: 700;
  }

  .mobile-drawer__languages {
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--color-border);
  }

  .mobile-drawer__label {
    padding: 4px 12px 8px;
    color: var(--color-muted);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.06em;
  }

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

@media (max-width: 768px) {
  :root {
    --gutter: 20px;
    --section-space: 72px;
  }

  h1 {
    font-size: clamp(26px, 7vw, 30px);
    line-height: 1.16;
  }

  h2 {
    font-size: clamp(24px, 6vw, 30px);
  }

  .section-lead {
    font-size: 16px;
  }

  .site-footer__main {
    gap: 36px 24px;
  }
}

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

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

  .language-button {
    min-width: 58px;
    padding-inline: 11px;
  }

  .language-button__full {
    display: none;
  }

  .language-button__short {
    display: inline;
  }

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

  .button-row .button,
  .button-row .btn {
    flex: 1 1 100%;
    width: 100%;
  }

  .site-footer {
    margin-top: 56px;
  }

  .site-footer__main {
    grid-template-columns: 1fr;
    padding-top: 48px;
  }

  .site-footer__bottom {
    align-items: flex-start;
    flex-direction: column;
  }

  .data-table {
    min-width: 620px;
  }

  .badge,
  .fact-chip {
    white-space: normal;
  }
}

@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 {
    opacity: 1;
    transform: none;
  }
}