:root {
  --color-canvas: #F3F3F3;
  --color-surface: #FFFFFF;
  --color-surface-muted: #EBECEF;
  --color-line: #DFE0E4;
  --color-brand: #544CC9;
  --color-brand-deep: #3E37A4;
  --color-brand-soft: #A9A5E6;
  --color-brand-wash: #EEEFFA;
  --color-ink: #2A2B33;
  --color-ink-muted: #6B6D78;
  --color-success: #2FA98C;
  --color-success-deep: #1F806A;
  --color-warning: #F08A3C;
  --color-warning-deep: #A94F10;
  --color-error: #E25563;
  --color-error-deep: #A42E3B;
  --color-sky-top: #D9EBF6;
  --color-sky-bottom: #E9F2F6;
  --color-hill-pale: #DCF1EA;
  --color-hill-light: #BFE8DD;
  --color-hill-mid: #7ACBB4;
  --color-hill-main: #2FA98C;
  --color-hill-deep: #1F8A70;
  --color-flag-red: #C7353C;
  --color-flag-blue: #304D91;
  --color-code-bg: #25262E;
  --color-code-ink: #F3F3F3;
  --color-code-key: #BFE8DD;
  --color-code-string: #F5B27E;
  --color-code-comment: #B9BBC4;
  --color-focus: #3E37A4;
  --color-overlay: rgba(42, 43, 51, 0.42);
  --color-fab-shadow: rgba(62, 55, 164, 0.22);
  --color-tile-shadow: rgba(18, 74, 59, 0.16);

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

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-pill: 999px;

  --header-height: 72px;
  --content-width: 1120px;
  --wide-width: 1280px;
  --reading-width: 760px;
  --gutter: clamp(16px, 3.2vw, 32px);

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 72px;
  --space-9: 104px;

  --duration-fast: 160ms;
  --duration-normal: 420ms;
  --ease-standard: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  min-width: 0;
}

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

html.nav-open {
  overflow: hidden;
}

body {
  margin: 0;
  overflow-x: clip;
  background: var(--color-canvas);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.72;
  text-rendering: optimizeLegibility;
}

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

img {
  height: auto;
}

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

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

button {
  border: 0;
}

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

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

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

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

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

h1,
h2,
h3,
h4 {
  color: var(--color-ink);
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.22;
  text-wrap: balance;
}

h1 {
  margin-bottom: var(--space-5);
  font-size: clamp(34px, 4vw, 48px);
  letter-spacing: -0.018em;
}

h2 {
  margin-bottom: var(--space-4);
  font-size: clamp(28px, 3vw, 40px);
  letter-spacing: -0.012em;
}

h3 {
  margin-bottom: var(--space-3);
  font-size: clamp(21px, 2vw, 27px);
}

h4 {
  margin-bottom: var(--space-2);
  font-size: 18px;
  font-weight: 650;
}

p {
  margin-bottom: var(--space-4);
}

strong {
  font-weight: 700;
}

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

hr {
  margin-block: var(--space-7);
  border: 0;
  border-top: 1px solid var(--color-line);
}

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

li + li {
  margin-top: var(--space-2);
}

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

:not(pre) > code {
  padding: 0.15em 0.42em;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-muted);
  color: var(--color-ink);
  font-size: 0.88em;
  overflow-wrap: anywhere;
}

pre {
  max-width: 100%;
  overflow-x: auto;
  padding: var(--space-5);
  border-radius: var(--radius-md);
  background: var(--color-code-bg);
  color: var(--color-code-ink);
  font-size: 14px;
  line-height: 1.7;
  tab-size: 2;
  -webkit-overflow-scrolling: touch;
}

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

.code-key {
  color: var(--color-code-key);
}

.code-string {
  color: var(--color-code-string);
}

.code-comment {
  color: var(--color-code-comment);
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-surface);
  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-surface-muted);
  color: var(--color-ink);
  font-weight: 700;
}

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

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

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

.section {
  padding-top: var(--space-9);
  padding-bottom: var(--space-9);
  overflow-x: clip;
}

.section--surface {
  background: var(--color-surface);
  color: var(--color-ink);
}

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

.section-heading {
  max-width: 760px;
  margin-bottom: var(--space-7);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
  color: var(--color-brand-deep);
  font-size: 13px;
  font-weight: 750;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 8px;
  height: 8px;
  flex-shrink: 0;
  border-radius: var(--radius-pill);
  background: var(--color-success);
  content: "";
}

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

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

.cluster {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.stack > * + * {
  margin-top: var(--space-4);
}

.grid {
  display: grid;
  gap: var(--space-5);
}

.grid > *,
.cluster > * {
  min-width: 0;
}

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

.grid--3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

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

.panel {
  padding: clamp(22px, 3vw, 36px);
}

.card {
  padding: var(--space-5);
}

.tilt,
.tilt-left,
.tilt-right {
  transform: none;
}

.button,
.btn-main,
.btn-secondary,
.btn-quiet {
  display: inline-flex;
  min-height: 48px;
  max-width: 100%;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 24px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  cursor: pointer;
  font-weight: 700;
  line-height: 1.25;
  text-align: center;
  text-decoration: none;
  transition:
    transform var(--duration-fast) ease,
    background-color var(--duration-fast) ease,
    border-color var(--duration-fast) ease,
    color var(--duration-fast) ease;
}

.button svg,
.btn-main svg,
.btn-secondary svg,
.btn-quiet svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.button--primary,
.btn-main {
  background: var(--color-brand);
  color: var(--color-surface);
}

.button--primary:hover,
.btn-main:hover {
  transform: translateY(-1px);
  background: var(--color-brand-deep);
  color: var(--color-surface);
}

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

.button--secondary:hover,
.btn-secondary:hover {
  background: var(--color-brand-wash);
  color: var(--color-brand-deep);
}

.button--quiet,
.btn-quiet {
  min-height: 44px;
  padding-inline: 10px;
  background: transparent;
  color: var(--color-brand-deep);
}

.button--quiet:hover,
.btn-quiet:hover {
  background: var(--color-brand-wash);
  color: var(--color-brand-deep);
}

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

.site-topbar {
  position: relative;
  z-index: 120;
  border-bottom: 1px solid var(--color-line);
  background: var(--color-surface);
  color: var(--color-ink);
}

.site-topbar__inner {
  width: 100%;
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  min-height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: var(--space-5);
}

.site-brand {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 11px;
  color: var(--color-ink);
  font-size: 17px;
  font-weight: 750;
  text-decoration: none;
}

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

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

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

.desktop-nav__links {
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.35vw, 34px);
}

.desktop-nav a {
  color: var(--color-ink-muted);
  font-size: 14.5px;
  font-weight: 550;
  text-decoration: none;
}

.desktop-nav a:hover {
  color: var(--color-ink);
}

.desktop-nav a.is-active,
.desktop-nav a[aria-current="page"] {
  color: var(--color-brand-deep);
  font-weight: 750;
}

.header-tools {
  display: flex;
  flex-shrink: 0;
  align-items: center;
  gap: var(--space-2);
}

.language-switch {
  position: relative;
}

.language-trigger,
.menu-trigger {
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-ink-muted);
  cursor: pointer;
}

.language-trigger {
  padding: 8px 15px;
  white-space: nowrap;
}

.language-trigger:hover,
.menu-trigger:hover {
  border-color: var(--color-ink-muted);
  color: var(--color-ink);
}

.language-trigger__short {
  display: none;
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 135;
  width: 176px;
  padding: var(--space-2);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-ink);
}

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

.language-menu a {
  display: flex;
  min-height: 44px;
  width: 100%;
  align-items: center;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: var(--color-ink);
  text-decoration: none;
}

.language-menu a:hover,
.language-menu a[aria-current="true"] {
  background: var(--color-brand-wash);
  color: var(--color-brand-deep);
}

.menu-trigger {
  display: none;
  padding: 10px;
}

.menu-trigger span,
.menu-trigger::before,
.menu-trigger::after {
  display: block;
  width: 20px;
  height: 2px;
  margin-inline: auto;
  border-radius: var(--radius-pill);
  background: var(--color-ink);
  content: "";
  transition: transform var(--duration-fast) ease, opacity var(--duration-fast) ease;
}

.menu-trigger span {
  margin-block: 4px;
}

.menu-trigger[aria-expanded="true"]::before {
  transform: translateY(6px) rotate(45deg);
}

.menu-trigger[aria-expanded="true"] span {
  opacity: 0;
}

.menu-trigger[aria-expanded="true"]::after {
  transform: translateY(-6px) rotate(-45deg);
}

.mobile-drawer {
  display: none;
}

.nav-veil {
  position: fixed;
  inset: var(--header-height) 0 0;
  z-index: 105;
  background: var(--color-overlay);
}

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

.site-footer {
  padding-top: var(--space-8);
  padding-bottom: var(--space-5);
  border-top: 1px solid var(--color-line);
  background: var(--color-surface);
  color: var(--color-ink);
}

.site-footer__grid {
  display: grid;
  grid-template-columns: minmax(250px, 1.25fr) repeat(3, minmax(150px, 1fr));
  gap: var(--space-6);
}

.footer-brand p {
  max-width: 380px;
  margin-top: var(--space-4);
  color: var(--color-ink-muted);
}

.footer-title {
  margin-bottom: var(--space-3);
  color: var(--color-ink);
  font-size: 14px;
  font-weight: 750;
}

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

.footer-links li + li {
  margin-top: var(--space-2);
}

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

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: var(--space-4);
  margin-top: var(--space-7);
  padding-top: var(--space-5);
  border-top: 1px solid var(--color-line);
  color: var(--color-ink-muted);
  font-size: 13px;
}

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

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

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

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

.prose h2 {
  margin-top: var(--space-8);
}

.prose h3 {
  margin-top: var(--space-6);
}

.prose a {
  overflow-wrap: anywhere;
}

.prose img {
  margin-block: var(--space-5);
  border-radius: var(--radius-md);
}

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

.icon,
.status-dot,
.badge-dot {
  flex-shrink: 0;
}

.decorated-section,
.hero,
.preview-hero,
.visual-stage {
  overflow-x: clip;
}

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

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

  .menu-trigger {
    display: block;
  }

  .mobile-drawer {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 130;
    display: block;
    max-height: calc(100dvh - var(--header-height));
    overflow-y: auto;
    padding: var(--space-3) var(--gutter) var(--space-5);
    border-top: 1px solid var(--color-line);
    background: var(--color-surface);
    color: var(--color-ink);
    overscroll-behavior: contain;
  }

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

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

  .mobile-drawer a.is-active,
  .mobile-drawer a[aria-current="page"] {
    color: var(--color-brand-deep);
    font-weight: 750;
  }

  .mobile-drawer__languages {
    margin-top: var(--space-4);
  }

  .mobile-drawer__label {
    margin: 0;
    padding: 8px 12px;
    color: var(--color-ink-muted);
    font-size: 13px;
    font-weight: 700;
  }

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

@media (max-width: 768px) {
  h1 {
    font-size: clamp(24px, 7vw, 30px);
    line-height: 1.28;
    letter-spacing: -0.01em;
  }

  h2 {
    font-size: clamp(25px, 7vw, 32px);
  }

  .section {
    padding-top: var(--space-8);
    padding-bottom: var(--space-8);
  }

  .grid--3,
  .grid--2 {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
  }
}

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

  body {
    font-size: 15.5px;
  }

  .site-topbar__inner {
    min-height: var(--header-height);
    gap: var(--space-2);
  }

  .site-brand {
    gap: 8px;
    font-size: 15px;
  }

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

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

  .language-trigger {
    padding-inline: 12px;
  }

  .language-trigger__full {
    display: none;
  }

  .language-trigger__short {
    display: inline;
  }

  .panel,
  .card {
    padding: 20px;
  }

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

  .cluster,
  .chip-row,
  .badge-row {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .site-footer__grid {
    grid-template-columns: 1fr;
  }

  pre {
    padding: 18px;
    font-size: 13px;
  }

  th,
  td {
    padding: 12px;
  }
}

@media (max-width: 390px) {
  .site-brand__name {
    max-width: 116px;
    overflow-wrap: anywhere;
    line-height: 1.2;
  }

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

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

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

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