:root {
  --color-bg: #FFFFFF;
  --color-panel: #FAFBFB;
  --color-panel-strong: #F2F6F5;
  --color-border: #E1E6E4;
  --color-border-strong: #C8D2CE;
  --color-grid: #EEF2F1;
  --color-accent: #00B893;
  --color-accent-dark: #00795F;
  --color-accent-soft: #E3F5F0;
  --color-text: #0D1312;
  --color-text-muted: #5D6763;
  --color-success: #12A150;
  --color-warning: #EFA400;
  --color-error: #D64530;
  --color-overlay: rgba(13, 19, 18, 0.48);
  --color-transparent: transparent;
  --font-display: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', 'Consolas', 'Menlo', monospace;
  --radius-none: 0;
  --radius-logo: 6px;
  --header-height: 64px;
  --content-width: 1120px;
  --wide-width: 1360px;
  --gutter: 40px;
  --section-space: 112px;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --shadow-focus: 0 0 0 3px var(--color-accent-soft);
  --transition-fast: 160ms ease;
  --transition-reveal: 560ms ease;
}

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

html {
  min-width: 320px;
  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-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  text-rendering: optimizeLegibility;
}

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

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

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

svg[data-full-bleed] {
  width: 100%;
  height: 100%;
}

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

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

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

button {
  border: 0;
  cursor: pointer;
}

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

:focus-visible {
  outline: 2px solid var(--color-accent-dark);
  outline-offset: 3px;
}

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

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

h1,
h2,
h3,
h4 {
  color: var(--color-text);
  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, 3.5vw, 48px);
  letter-spacing: -0.015em;
}

h2 {
  margin-bottom: var(--space-5);
  font-size: clamp(28px, 3vw, 38px);
  letter-spacing: -0.012em;
}

h3 {
  margin-bottom: var(--space-4);
  font-size: clamp(21px, 2vw, 26px);
}

h4 {
  margin-bottom: var(--space-3);
  font-size: 18px;
}

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

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

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

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

small {
  font-size: 0.875rem;
}

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

:not(pre) > code {
  padding: 0.12em 0.36em;
  border: 1px solid var(--color-border);
  background: var(--color-panel-strong);
  color: var(--color-text);
  overflow-wrap: anywhere;
}

pre {
  max-width: 100%;
  margin-bottom: var(--space-5);
  padding: var(--space-5);
  overflow-x: auto;
  border: 1px solid var(--color-border-strong);
  background: var(--color-panel);
  color: var(--color-text);
  line-height: 1.65;
  -webkit-overflow-scrolling: touch;
}

pre code {
  padding: 0;
  border: 0;
  background: var(--color-transparent);
  color: inherit;
  overflow-wrap: normal;
  white-space: pre;
}

hr {
  height: 1px;
  margin: var(--space-7) 0;
  border: 0;
  background: var(--color-border);
}

table {
  width: 100%;
  border-collapse: collapse;
  color: var(--color-text);
}

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

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

caption {
  margin-bottom: var(--space-3);
  color: var(--color-text-muted);
  text-align: left;
}

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

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

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

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

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

.section-band {
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  background: linear-gradient(90deg, var(--color-panel-strong), var(--color-accent-soft), var(--color-panel-strong));
  color: var(--color-text);
}

.section-kicker,
.mono-note {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.section-kicker {
  margin-bottom: var(--space-4);
  color: var(--color-accent-dark);
}

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

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

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

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

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

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 24px;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-none);
  background: var(--color-bg);
  color: var(--color-text);
  font-weight: 600;
  line-height: 1.2;
  text-align: center;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast);
}

.button:hover {
  border-color: var(--color-accent-dark);
  background: var(--color-panel-strong);
  color: var(--color-accent-dark);
}

.button-primary {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-bg);
}

.button-primary:hover {
  border-color: var(--color-accent-dark);
  background: var(--color-accent-dark);
  color: var(--color-bg);
}

.button-danger {
  border-color: var(--color-error);
  background: var(--color-error);
  color: var(--color-bg);
}

.button:disabled,
.button[aria-disabled="true"] {
  cursor: not-allowed;
  opacity: 0.56;
}

.icon-button {
  display: inline-grid;
  width: 44px;
  min-width: 44px;
  height: 44px;
  min-height: 44px;
  place-items: center;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
}

.panel,
.card {
  min-width: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-none);
  background: var(--color-bg);
  color: var(--color-text);
}

.panel {
  padding: clamp(22px, 4vw, 42px);
}

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

.card-head {
  display: flex;
  min-width: 0;
  align-items: flex-start;
  gap: var(--space-4);
}

.card-head > svg,
.card-head > img,
.card-icon,
.status-dot {
  flex-shrink: 0;
}

.status-dot {
  width: 8px;
  height: 8px;
  background: var(--color-success);
}

.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: var(--space-5);
}

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

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

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

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

.prose h2,
.prose h3,
.prose h4 {
  margin-top: var(--space-8);
}

.prose a {
  color: var(--color-accent-dark);
  text-decoration: underline;
  text-underline-offset: 0.18em;
}

.prose img {
  height: auto;
}

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

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

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

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

.site-head {
  position: relative;
  z-index: 100;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
}

.head-inner {
  width: 100%;
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 32px;
}

.brand {
  display: inline-flex;
  min-width: 0;
  align-items: center;
  gap: 11px;
  flex-shrink: 0;
}

.brand img,
.brand-mark {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
}

.brand-name {
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

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

.desktop-nav > ul,
.nav-more-panel,
.mobile-nav ul,
.footer-links,
.footer-keywords,
.footer-languages {
  margin: 0;
  padding: 0;
  list-style: none;
}

.desktop-nav > ul {
  display: flex;
  align-items: center;
  gap: 6px;
}

.desktop-nav li {
  margin: 0;
}

.desktop-nav a {
  display: flex;
  min-height: 44px;
  align-items: center;
  padding: 6px 14px;
  border: 1px solid var(--color-transparent);
  color: var(--color-text-muted);
  font-size: 14.5px;
}

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

.desktop-nav a[aria-current="page"],
.nav-more.is-active > .nav-more-trigger {
  padding-bottom: 4px;
  border-bottom: 2px solid var(--color-accent);
  color: var(--color-text);
}

.nav-more {
  position: relative;
}

.nav-more-trigger::after {
  content: "▾";
  margin-left: 7px;
  color: var(--color-text-muted);
  font-size: 11px;
}

.nav-more-panel {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  display: none;
  min-width: 170px;
  padding: 6px 0;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
}

.nav-more:hover .nav-more-panel,
.nav-more:focus-within .nav-more-panel {
  display: block;
}

.nav-more-panel a {
  width: 100%;
  padding: 10px 18px;
}

.nav-more-note {
  display: block;
  padding: 7px 18px 4px;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.07em;
}

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

.language-menu {
  position: relative;
}

.language-button {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  gap: 7px;
  padding: 7px 13px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text-muted);
  white-space: nowrap;
}

.language-button:hover {
  border-color: var(--color-text-muted);
  color: var(--color-text);
}

.language-button svg {
  width: 14px;
  height: 14px;
}

.language-short {
  display: none;
}

.language-panel {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  display: none;
  min-width: 160px;
  padding: 6px 0;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
}

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

.language-panel a {
  display: flex;
  width: 100%;
  min-height: 44px;
  align-items: center;
  padding: 8px 16px;
  color: var(--color-text-muted);
}

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

.menu-button {
  display: none;
  width: 44px;
  min-width: 44px;
  height: 44px;
  min-height: 44px;
  padding: 10px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
}

.menu-button-lines,
.menu-button-lines::before,
.menu-button-lines::after {
  display: block;
  width: 20px;
  height: 1px;
  background: var(--color-text);
}

.menu-button-lines {
  position: relative;
  margin-inline: auto;
}

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

.menu-button-lines::before {
  top: -6px;
}

.menu-button-lines::after {
  top: 6px;
}

.mobile-nav {
  position: fixed;
  z-index: 103;
  top: var(--header-height);
  right: 0;
  left: 0;
  display: none;
  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-bg);
  color: var(--color-text);
}

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

.mobile-nav ul {
  padding: 8px var(--gutter) 18px;
}

.mobile-nav li {
  margin: 0;
  border-bottom: 1px solid var(--color-border);
}

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 48px;
  align-items: center;
  justify-content: space-between;
  padding: 10px 2px;
  color: var(--color-text-muted);
}

.mobile-nav a[aria-current="page"] {
  color: var(--color-text);
}

.mobile-nav-label {
  padding: 18px 2px 6px;
  color: var(--color-accent-dark);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
}

.mobile-nav-veil {
  position: fixed;
  z-index: 99;
  inset: var(--header-height) 0 0;
  display: none;
  background: var(--color-overlay);
}

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

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

.footer-main {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 1.25fr 0.8fr;
  gap: 44px;
  padding-top: 64px;
  padding-bottom: 56px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 11px;
  margin-bottom: 16px;
}

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

.footer-title {
  color: var(--color-text);
  font-weight: 600;
}

.footer-copy {
  max-width: 320px;
  color: var(--color-text-muted);
  font-size: 14px;
}

.footer-heading {
  margin-bottom: 15px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.09em;
}

.footer-links li,
.footer-keywords li,
.footer-languages li {
  margin: 0;
}

.footer-links a,
.footer-keywords a,
.footer-languages a {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  color: var(--color-text-muted);
  font-size: 14px;
}

.footer-bottom {
  padding-top: 18px;
  padding-bottom: 18px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 12px;
}

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

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

@media (max-width: 1080px) {
  .desktop-nav {
    display: none;
  }

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

  .menu-button {
    display: block;
  }

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

@media (max-width: 768px) {
  :root {
    --gutter: 20px;
    --section-space: 80px;
  }

  h1 {
    font-size: clamp(24px, 7.5vw, 30px);
    line-height: 1.2;
  }

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

  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .language-full {
    display: none;
  }

  .language-short {
    display: inline;
  }
}

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

  body {
    overflow-x: clip;
  }

  .head-inner {
    gap: 12px;
  }

  .brand-name {
    display: none;
  }

  .language-button {
    min-width: 44px;
    justify-content: center;
    padding-inline: 9px;
  }

  .grid-2,
  .grid-3,
  .grid-4,
  .footer-main {
    grid-template-columns: minmax(0, 1fr);
  }

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

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

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

  pre,
  .data-table {
    max-width: 100%;
    overflow-x: auto;
  }

  .footer-main {
    gap: 34px;
    padding-top: 48px;
    padding-bottom: 42px;
  }
}