:root {
  --color-bg: #F6F9F8;
  --color-panel: #FFFFFF;
  --color-panel-soft: #EEF4F1;
  --color-tile: #F3F7F5;
  --color-border: #E3EAE8;
  --color-accent: #1FA463;
  --color-accent-dark: #157A48;
  --color-text: #1F2A26;
  --color-muted: #66736E;
  --color-success: #1FA463;
  --color-warning: #D99A1E;
  --color-error: #D9534F;
  --color-accent-soft: rgba(31, 164, 99, 0.12);
  --color-accent-ring: rgba(31, 164, 99, 0.22);
  --color-field-mint: rgba(31, 164, 99, 0.11);
  --color-field-sky: rgba(112, 168, 232, 0.14);
  --color-shadow: rgba(20, 40, 32, 0.08);
  --color-shadow-near: rgba(20, 40, 32, 0.07);
  --color-shadow-far: rgba(20, 40, 32, 0.10);
  --color-button-shadow: rgba(31, 164, 99, 0.28);
  --color-white-line: rgba(255, 255, 255, 0.70);
  --color-veil: rgba(31, 42, 38, 0.36);

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

  --radius-xl: 28px;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 12px;
  --radius-xs: 8px;
  --radius-pill: 999px;

  --shadow-card: 0 24px 64px var(--color-shadow);
  --shadow-float: 0 8px 24px var(--color-shadow-near), 0 40px 90px var(--color-shadow-far);
  --shadow-mini: 0 6px 18px var(--color-shadow-near), 0 20px 48px var(--color-shadow);
  --shadow-button: 0 10px 24px var(--color-button-shadow);

  --header-height: 72px;
  --content-width: 1180px;
  --header-width: 1280px;
  --reading-width: 820px;
  --gutter: clamp(16px, 3vw, 32px);
  --section-space: clamp(72px, 9vw, 128px);
  --transition-fast: 180ms ease;
  --transition-reveal: 680ms cubic-bezier(0.22, 1, 0.36, 1);
}

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

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

html.nav-open {
  overflow: hidden;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: clip;
  color: var(--color-text);
  background: var(--color-bg);
  font-family: var(--font-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

img {
  height: auto;
}

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

button {
  cursor: pointer;
}

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

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--color-accent-ring);
  outline-offset: 3px;
}

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

p {
  margin-bottom: 1.15em;
}

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

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

:not(pre) > code {
  padding: 0.14em 0.38em;
  overflow-wrap: anywhere;
  color: var(--color-accent-dark);
  background: var(--color-panel-soft);
  border-radius: var(--radius-xs);
}

pre {
  max-width: 100%;
  padding: 20px;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  color: var(--color-text);
  background: var(--color-panel-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font: 13px/1.75 var(--font-mono);
  -webkit-overflow-scrolling: touch;
}

pre code {
  white-space: pre;
}

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  text-wrap: balance;
}

h1 {
  margin-bottom: 24px;
  font-size: clamp(34px, 4vw, 48px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.14;
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(30px, 3.2vw, 42px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.18;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(21px, 2vw, 28px);
  font-weight: 750;
  letter-spacing: -0.015em;
  line-height: 1.3;
}

h4 {
  margin-bottom: 10px;
  font-size: 18px;
  line-height: 1.4;
}

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

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

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

.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);
}

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

.section--panel {
  color: var(--color-text);
  background: var(--color-panel);
  border-block: 1px solid var(--color-border);
}

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

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

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 30px;
  margin: 0 0 16px;
  padding: 4px 11px;
  color: var(--color-muted);
  background: var(--color-panel-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  font-size: 13px;
  font-weight: 650;
}

.section-kicker svg,
.inline-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

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

.card {
  padding: clamp(22px, 3vw, 32px);
}

.panel {
  padding: clamp(24px, 4vw, 44px);
}

.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: 20px;
}

.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));
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 10px 22px;
  color: var(--color-text);
  background: var(--color-panel);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-weight: 700;
  line-height: 1.2;
  transition: transform var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast), box-shadow var(--transition-fast);
}

.button:hover {
  border-color: var(--color-muted);
  transform: translateY(-1px);
}

.button:active {
  transform: translateY(0);
}

.button[aria-disabled="true"],
.button:disabled {
  cursor: not-allowed;
  opacity: 0.58;
  transform: none;
}

.button svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.button--primary {
  color: var(--color-panel);
  background: var(--color-accent-dark);
  border-color: var(--color-accent-dark);
  box-shadow: var(--shadow-button);
}

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

.button--small {
  min-height: 40px;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 14px;
}

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

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

.site-header--overlay {
  position: absolute;
  inset: 0 0 auto;
}

.header-shell {
  width: 100%;
  max-width: min(100%, calc(var(--header-width) + var(--gutter) * 2));
  height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 36px;
}

.site-brand {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 750;
  letter-spacing: -0.01em;
}

.site-brand img {
  width: 31px;
  height: 31px;
  flex-shrink: 0;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.2vw, 30px);
}

.desktop-nav a {
  position: relative;
  padding-block: 12px;
  color: var(--color-muted);
  font-size: 15px;
  font-weight: 550;
  transition: color var(--transition-fast);
}

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

.desktop-nav a[aria-current="page"] {
  font-weight: 700;
}

.desktop-nav a[aria-current="page"]::after {
  position: absolute;
  right: 0;
  bottom: 7px;
  left: 0;
  height: 2px;
  content: "";
  background: var(--color-accent);
  border-radius: var(--radius-pill);
}

.header-tools {
  position: relative;
  z-index: 104;
  display: flex;
  margin-left: auto;
  align-items: center;
  gap: 8px;
}

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

.language-button {
  min-width: 112px;
  gap: 7px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 650;
}

.language-short {
  display: none;
}

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

.language-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 170px;
  padding: 7px;
  color: var(--color-text);
  background: var(--color-panel);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-mini);
}

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

.language-menu a {
  display: flex;
  width: 100%;
  min-height: 42px;
  align-items: center;
  padding: 8px 11px;
  border-radius: var(--radius-sm);
  font-size: 14px;
}

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

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

.menu-button-lines,
.menu-button-lines::before,
.menu-button-lines::after {
  width: 19px;
  height: 2px;
  background: var(--color-text);
  border-radius: var(--radius-pill);
}

.menu-button-lines {
  position: relative;
}

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

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

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

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

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

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

.mobile-drawer {
  display: none;
}

.mobile-veil {
  display: none;
}

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

.footer-grid {
  display: grid;
  grid-template-columns: minmax(240px, 1.25fr) repeat(3, minmax(0, 1fr));
  gap: 42px;
  padding-top: 64px;
  padding-bottom: 42px;
}

.footer-brand {
  max-width: 320px;
}

.footer-brand .site-brand {
  margin-bottom: 15px;
}

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

.footer-column h2 {
  margin-bottom: 16px;
  font-size: 14px;
  letter-spacing: 0;
}

.footer-links {
  display: grid;
  gap: 9px;
}

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

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

.footer-bottom {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding-block: 18px;
  color: var(--color-muted);
  border-top: 1px solid var(--color-border);
  font-size: 13px;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

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

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

.prose {
  overflow-wrap: break-word;
}

.prose h2,
.prose h3 {
  scroll-margin-top: calc(var(--header-height) + 28px);
}

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

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

.prose a:not([class*="button"]) {
  color: var(--color-accent-dark);
  text-decoration: underline;
  text-decoration-color: var(--color-accent-ring);
  text-underline-offset: 0.18em;
}

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

.data-table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
  color: var(--color-text);
  background: var(--color-panel);
}

.data-table th,
.data-table td {
  padding: 15px 17px;
  border-bottom: 1px solid var(--color-border);
  text-align: left;
  vertical-align: top;
}

.data-table th {
  color: var(--color-text);
  background: var(--color-panel-soft);
  font-size: 13px;
}

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

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

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

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

@media (max-width: 960px) {
  .desktop-nav {
    gap: 16px;
  }

  .desktop-nav a {
    font-size: 14px;
  }

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

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

@media (max-width: 780px) {
  h1 {
    font-size: clamp(24px, 7.4vw, 30px);
    line-height: 1.18;
  }

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

  .desktop-nav,
  .language-menu {
    display: none;
  }

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

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

  .mobile-veil {
    position: fixed;
    inset: var(--header-height) 0 0;
    z-index: 98;
    display: block;
    background: var(--color-veil);
  }

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

  .mobile-drawer {
    position: fixed;
    top: var(--header-height);
    right: 0;
    left: 0;
    z-index: 102;
    display: block;
    max-height: calc(100dvh - var(--header-height));
    padding: 8px var(--gutter) 18px;
    overflow-y: auto;
    overscroll-behavior: contain;
    color: var(--color-text);
    background: var(--color-panel);
    border-top: 1px solid var(--color-border);
    box-shadow: var(--shadow-mini);
  }

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

  .mobile-drawer a {
    display: flex;
    width: 100%;
    min-height: 48px;
    align-items: center;
    padding: 10px 12px;
    border-bottom: 1px solid var(--color-border);
    font-weight: 650;
  }

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

  .mobile-language-title {
    margin: 16px 12px 4px;
    color: var(--color-muted);
    font-size: 12px;
    font-weight: 700;
  }

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

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

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
    --section-space: 68px;
  }

  .language-button {
    min-width: 54px;
    padding-inline: 10px;
  }

  .language-full {
    display: none;
  }

  .language-short {
    display: inline;
  }

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

  .button-row {
    align-items: stretch;
    flex-direction: column;
  }

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

  .grid-2,
  .grid-4,
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

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

  .section,
  .hero,
  [class*="atmosphere"],
  [class*="decor"] {
    overflow-x: clip;
  }

  .data-table {
    min-width: 560px;
  }
}