:root {
  --color-page: #FFFFFF;
  --color-panel: #F6F7F9;
  --color-panel-strong: #EEF0F4;
  --color-line: #E4E7EC;
  --color-accent: #1D55F0;
  --color-accent-deep: #123CB8;
  --color-accent-soft: #EDF2FE;
  --color-ink: #0E1116;
  --color-ink-muted: #5C6472;
  --color-success: #14894E;
  --color-warning: #B97800;
  --color-error: #D23B3B;
  --color-success-soft: #EAF7F0;
  --color-warning-soft: #FFF6E5;
  --color-error-soft: #FDEEEE;
  --color-overlay: rgba(14, 17, 22, 0.42);
  --color-shadow-soft: rgba(14, 17, 22, 0.04);
  --color-shadow-depth: rgba(14, 17, 22, 0.14);

  --font-display: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', -apple-system, sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, 'Courier New', monospace;

  --radius-xs: 7px;
  --radius-sm: 9px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-xl: 30px;
  --radius-pill: 999px;

  --shadow-line: 0 1px 1px var(--color-shadow-soft);
  --shadow-card: 0 1px 2px var(--color-shadow-soft), 0 16px 40px -24px var(--color-shadow-depth);

  --wrap: 1200px;
  --reading-wrap: 820px;
  --header-wrap: 1280px;
  --gutter: 32px;
  --header-height: 66px;
  --section-space: 104px;
  --motion-fast: 150ms;
  --motion-normal: 420ms;
}

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

html {
  background: var(--color-page);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  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-ink);
  -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%;
}

svg {
  flex-shrink: 0;
}

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

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

button {
  color: inherit;
}

a {
  color: var(--color-accent-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--color-accent);
}

p,
ul,
ol,
dl,
blockquote,
pre,
figure,
table {
  margin-top: 0;
  margin-bottom: 1.25em;
}

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

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--color-ink);
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.2;
  text-wrap: balance;
}

h1 {
  margin-bottom: 24px;
  font-size: clamp(34px, 3.35vw, 48px);
  font-weight: 400;
  letter-spacing: -0.015em;
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(30px, 3vw, 42px);
  font-weight: 400;
  letter-spacing: -0.012em;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(21px, 2vw, 27px);
}

h4 {
  margin-bottom: 10px;
  font-size: 18px;
}

strong {
  color: var(--color-ink);
  font-weight: 600;
}

small {
  font-size: 0.875rem;
}

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

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

pre {
  max-width: 100%;
  padding: 18px 20px;
  overflow-x: auto;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.72;
  tab-size: 2;
  -webkit-overflow-scrolling: touch;
}

pre code {
  color: inherit;
  white-space: pre;
}

hr {
  height: 1px;
  margin: 56px 0;
  border: 0;
  background: var(--color-line);
}

table {
  width: 100%;
  border-spacing: 0;
  border-collapse: collapse;
  color: var(--color-ink);
}

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

th {
  background: var(--color-panel);
  color: var(--color-ink);
  font-weight: 600;
}

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

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

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

.header-wrap {
  width: 100%;
  max-width: min(100%, calc(var(--header-wrap) + 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;
  border-top: 1px solid var(--color-line);
  background: var(--color-page);
  color: var(--color-ink);
}

.section-heading {
  max-width: 760px;
  margin-bottom: 48px;
}

.section-kicker {
  margin-bottom: 12px;
  color: var(--color-ink-muted);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

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

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

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

.panel,
.card {
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-page);
  color: var(--color-ink);
}

.panel {
  padding: 28px;
}

.panel-soft {
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-ink);
}

.card {
  padding: 24px;
  box-shadow: var(--shadow-line);
}

.card-title {
  margin-bottom: 8px;
  font-size: 20px;
}

.card-copy {
  margin-bottom: 0;
  color: var(--color-ink-muted);
}

.button,
.btn {
  min-height: 44px;
  padding: 13px 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  cursor: pointer;
  color: var(--color-ink);
  font-size: 15px;
  font-weight: 500;
  line-height: 1;
  text-align: center;
  text-decoration: none;
  transition:
    background-color var(--motion-fast) ease,
    border-color var(--motion-fast) ease,
    color var(--motion-fast) ease,
    transform var(--motion-fast) ease;
}

.button svg,
.btn svg {
  width: 16px;
  height: 16px;
}

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

.button-primary:hover,
.btn-main:hover {
  border-color: var(--color-accent-deep);
  background: var(--color-accent-deep);
  color: var(--color-page);
}

.button-secondary,
.btn-plain {
  border-color: var(--color-line);
  background: var(--color-page);
  color: var(--color-ink);
}

.button-secondary:hover,
.btn-plain:hover {
  border-color: var(--color-ink-muted);
  background: var(--color-panel);
  color: var(--color-ink);
}

.button:focus-visible,
.btn:focus-visible,
.nav-item:focus-visible,
.lang-button:focus-visible,
.menu-toggle:focus-visible {
  outline: 3px solid var(--color-accent-soft);
  outline-offset: 2px;
}

.button[disabled],
.button.is-disabled {
  cursor: not-allowed;
  border-color: var(--color-line);
  background: var(--color-panel-strong);
  color: var(--color-ink-muted);
  transform: none;
}

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

.site-head {
  position: relative;
  z-index: 40;
  border-bottom: 1px solid var(--color-line);
  background: var(--color-page);
  color: var(--color-ink);
}

.head-in {
  height: var(--header-height);
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 10px;
  color: var(--color-ink);
  text-decoration: none;
}

.brand:hover {
  color: var(--color-ink);
}

.brand-mark {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.brand-name {
  font-size: 16.5px;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 3px;
  margin-left: auto;
}

.nav-item {
  min-height: 42px;
  padding: 9px 11px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border-radius: var(--radius-pill);
  color: var(--color-ink);
  font-size: 13.5px;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color var(--motion-fast) ease, color var(--motion-fast) ease;
}

.nav-item svg {
  width: 16px;
  height: 16px;
  color: var(--color-ink-muted);
}

.nav-item:hover {
  background: var(--color-panel);
  color: var(--color-ink);
}

.nav-item.is-now {
  color: var(--color-accent-deep);
}

.nav-item.is-now svg {
  color: var(--color-accent);
}

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

.lang-menu {
  position: relative;
}

.lang-button {
  min-height: 38px;
  padding: 7px 14px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-pill);
  background: var(--color-page);
  color: var(--color-ink);
  cursor: pointer;
  font-size: 13px;
  white-space: nowrap;
}

.lang-button:hover {
  border-color: var(--color-ink-muted);
}

.lang-short {
  display: none;
}

.lang-caret {
  color: var(--color-ink-muted);
  font-size: 10px;
}

.lang-popover {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 55;
  width: 176px;
  padding: 7px;
  visibility: hidden;
  opacity: 0;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-page);
  color: var(--color-ink);
  box-shadow: var(--shadow-card);
  transform: translateY(-4px);
  transition: opacity var(--motion-fast) ease, transform var(--motion-fast) ease, visibility var(--motion-fast) ease;
}

.lang-menu.is-open .lang-popover {
  visibility: visible;
  opacity: 1;
  transform: translateY(0);
}

.lang-popover a {
  min-height: 42px;
  padding: 8px 11px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-sm);
  color: var(--color-ink);
  font-size: 13px;
  text-decoration: none;
}

.lang-popover a:hover,
.lang-popover a[aria-current="true"] {
  background: var(--color-panel);
  color: var(--color-accent-deep);
}

.menu-toggle {
  min-width: 44px;
  min-height: 44px;
  padding: 9px;
  display: none;
  align-items: center;
  justify-content: center;
  border: 0;
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-ink);
  cursor: pointer;
}

.menu-toggle svg {
  width: 21px;
  height: 21px;
}

.mobile-nav {
  position: absolute;
  top: var(--header-height);
  right: 0;
  left: 0;
  z-index: 52;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  padding: 10px var(--gutter) 20px;
  overflow-y: auto;
  overscroll-behavior: contain;
  border-bottom: 1px solid var(--color-line);
  background: var(--color-page);
  color: var(--color-ink);
}

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

.mobile-nav a {
  width: 100%;
  min-height: 48px;
  padding: 11px 12px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid var(--color-line);
  color: var(--color-ink);
  text-decoration: none;
}

.mobile-nav a svg {
  width: 18px;
  height: 18px;
  color: var(--color-ink-muted);
}

.mobile-nav a.is-now {
  color: var(--color-accent-deep);
}

.mobile-languages {
  padding-top: 12px;
}

.mobile-languages strong {
  padding: 8px 12px;
  display: block;
  color: var(--color-ink-muted);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.mobile-languages a {
  min-height: 44px;
  font-size: 14px;
}

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

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

.site-footer {
  padding-top: 72px;
  padding-bottom: 28px;
  border-top: 1px solid var(--color-line);
  background: var(--color-page);
  color: var(--color-ink);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.8fr 1.2fr 0.8fr;
  gap: 48px;
}

.footer-brand-copy {
  max-width: 330px;
  margin-top: 18px;
  color: var(--color-ink-muted);
  font-size: 14px;
}

.footer-title {
  margin-bottom: 14px;
  color: var(--color-ink);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
}

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

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

.footer-links a {
  color: var(--color-ink-muted);
  font-size: 13.5px;
  text-decoration: none;
}

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

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

.footer-keywords a {
  max-width: 100%;
  padding: 6px 10px;
  overflow-wrap: anywhere;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-pill);
  color: var(--color-ink-muted);
  font-size: 12px;
  text-decoration: none;
}

.footer-keywords a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent-deep);
}

.footer-bottom {
  margin-top: 46px;
  padding-top: 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 24px;
  border-top: 1px solid var(--color-line);
  color: var(--color-ink-muted);
  font-size: 12.5px;
}

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

.footer-legal a {
  color: var(--color-ink-muted);
  text-decoration: none;
}

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

.reveal.shown {
  opacity: 1;
  transform: translateY(0);
}

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

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

.prose h2 {
  margin-top: 2.1em;
  padding-top: 0.35em;
}

.prose h3 {
  margin-top: 1.7em;
}

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

.prose a {
  overflow-wrap: anywhere;
}

.prose figure {
  margin-inline: 0;
}

.prose figcaption {
  margin-top: 9px;
  color: var(--color-ink-muted);
  font-size: 13px;
}

.data-table-wrap,
.prose > .data-table {
  display: block;
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.tilt,
.tilt-card {
  transform: rotate(-0.35deg);
}

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

.decorative-absolute {
  position: absolute;
  inset-inline: 0;
  pointer-events: none;
}

.full-bleed-art svg {
  width: 100%;
  height: 100%;
}

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

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

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

@media (max-width: 1120px) {
  .main-nav {
    gap: 0;
  }

  .nav-item {
    padding-inline: 8px;
    font-size: 13px;
  }

  .head-in {
    gap: 16px;
  }
}

@media (max-width: 960px) {
  .main-nav,
  .desktop-lang {
    display: none;
  }

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

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

  .mobile-lang-button {
    display: inline-flex;
  }

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

@media (min-width: 961px) {
  .mobile-lang-button {
    display: none;
  }
}

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

  h1 {
    font-size: clamp(26px, 7.4vw, 30px);
    line-height: 1.16;
  }

  h2 {
    font-size: clamp(26px, 7vw, 34px);
  }

  .panel,
  .card {
    padding: 21px;
  }

  .footer-grid {
    gap: 36px 24px;
  }
}

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
    --header-height: 62px;
    --section-space: 62px;
  }

  .head-in {
    height: var(--header-height);
  }

  .brand-name {
    font-size: 15px;
  }

  .brand-mark {
    width: 27px;
    height: 27px;
  }

  .lang-full {
    display: none;
  }

  .lang-short {
    display: inline;
  }

  .lang-button {
    min-width: 44px;
    justify-content: center;
    padding-inline: 10px;
  }

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

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

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

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

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

  .footer-legal {
    margin-left: 0;
  }

  th,
  td {
    padding: 11px 12px;
  }
}