:root {
  --color-bg: #FAF4E6;
  --color-panel: #FFFDF7;
  --color-panel-alt: #F2E8D3;
  --color-border: #E2D5B9;
  --color-accent: #33241F;
  --color-accent-dark: #1F1409;
  --color-text: #3A2E21;
  --color-muted: #7C6D57;
  --color-success: #35803F;
  --color-warning: #B07A18;
  --color-error: #B3372B;
  --color-success-soft: rgba(53, 128, 63, .16);
  --color-shadow: rgba(51, 36, 31, .18);
  --color-shadow-strong: rgba(31, 20, 9, .45);
  --font-display: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Menlo, Consolas, 'Courier New', monospace;
  --radius-xs: 6px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-pill: 999px;
  --shadow-window: 0 30px 60px -28px rgba(51, 36, 31, .30), 0 10px 22px -12px rgba(51, 36, 31, .16);
  --shadow-button: 0 10px 20px -10px var(--color-shadow-strong);
  --shadow-soft: 0 8px 22px -12px var(--color-shadow);
  --header-height: 64px;
  --content-width: 1392px;
  --reading-width: 820px;
  --gutter: clamp(16px, 3vw, 28px);
  --section-space: clamp(64px, 9vw, 116px);
  --focus-width: 2px;
  --toc-offset: 124px;
  --transition-fast: 160ms ease;
  --transition-reveal: 620ms cubic-bezier(.2, .75, .25, 1);
}

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

html {
  min-width: 320px;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
}

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: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 80;
  pointer-events: none;
  opacity: .05;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='.55'/%3E%3C/svg%3E");
}

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

img {
  height: auto;
}

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

button {
  cursor: pointer;
}

a {
  color: var(--color-accent);
  text-decoration-thickness: .08em;
  text-underline-offset: .2em;
}

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

a,
button,
summary,
[role="tab"],
select,
input,
textarea {
  -webkit-tap-highlight-color: transparent;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible,
[role="tab"]:focus-visible,
select:focus-visible,
input:focus-visible,
textarea:focus-visible {
  outline: var(--focus-width) solid var(--color-accent);
  outline-offset: 3px;
}

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

p:last-child,
ul:last-child,
ol:last-child,
blockquote:last-child {
  margin-bottom: 0;
}

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

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

code {
  overflow-wrap: anywhere;
  padding: .1em .35em;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  background: var(--color-panel-alt);
  font-size: .9em;
}

pre {
  max-width: 100%;
  overflow-x: auto;
  padding: 18px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-accent-dark);
  color: var(--color-panel);
  line-height: 1.7;
  -webkit-overflow-scrolling: touch;
}

pre code {
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  overflow-wrap: normal;
}

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

h1 {
  margin-bottom: 24px;
  font-size: clamp(52px, 5vw, 72px);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.1;
}

h2 {
  margin-bottom: 20px;
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 900;
  letter-spacing: -.018em;
  line-height: 1.16;
}

h3 {
  margin-bottom: 14px;
  font-size: clamp(21px, 2.3vw, 28px);
  font-weight: 800;
  line-height: 1.25;
}

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

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

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

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

.section-tight {
  padding-top: clamp(42px, 6vw, 72px);
  padding-bottom: clamp(42px, 6vw, 72px);
  overflow-x: clip;
}

.section-head {
  max-width: 760px;
  margin-bottom: clamp(30px, 5vw, 56px);
}

.section-number {
  display: inline-block;
  margin-bottom: 12px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .08em;
}

.lead {
  max-width: 720px;
  color: var(--color-muted);
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.75;
}

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

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

.panel,
.card {
  min-width: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  box-shadow: var(--shadow-soft);
}

.card {
  padding: clamp(20px, 3vw, 30px);
}

.btn,
.btn-primary,
.btn-secondary,
.btn-quiet {
  display: inline-flex;
  min-width: 24px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border: 1.5px solid transparent;
  border-radius: 10px;
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  transition: color var(--transition-fast), background var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
}

.btn svg,
.btn-primary svg,
.btn-secondary svg,
.btn-quiet svg {
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
}

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

.btn-primary:hover {
  transform: translateY(-1px);
  background: var(--color-accent-dark);
  color: var(--color-panel);
}

.btn-secondary {
  border-color: var(--color-accent);
  background: transparent;
  color: var(--color-accent);
}

.btn-secondary:hover {
  background: var(--color-panel-alt);
}

.btn-quiet {
  border-color: var(--color-border);
  background: var(--color-panel);
  color: var(--color-text);
}

.btn[aria-disabled="true"],
.btn-primary[aria-disabled="true"],
.btn-secondary[aria-disabled="true"],
button:disabled {
  cursor: not-allowed;
  opacity: .5;
  transform: none;
}

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

.badge,
.tag,
.fact-pill {
  display: inline-flex;
  max-width: 100%;
  min-height: 24px;
  align-items: center;
  gap: 7px;
  padding: 4px 11px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-muted);
  font-size: 12px;
  font-weight: 700;
  line-height: 1.3;
}

.badge-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--color-success);
}

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

.reveal {
  transition: opacity var(--transition-reveal), transform var(--transition-reveal);
}

.reveal.pending {
  opacity: 0;
  transform: translateY(16px);
}

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

.site-header {
  position: relative;
  z-index: 70;
  height: var(--header-height);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
}

.header-inner {
  width: 100%;
  max-width: var(--content-width);
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  display: inline-flex;
  min-width: max-content;
  align-items: center;
  gap: 9px;
  color: var(--color-accent-dark);
  text-decoration: none;
}

.brand img {
  width: 30px;
  height: 30px;
  flex: 0 0 auto;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -.01em;
}

.brand-local {
  color: var(--color-muted);
  font-size: 14px;
  font-weight: 600;
}

.desktop-nav {
  display: flex;
  min-width: 0;
  flex: 1;
  align-items: center;
  gap: 2px;
}

.desktop-nav a {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  gap: 6px;
  padding: 7px 9px;
  border-radius: var(--radius-sm);
  color: var(--color-muted);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
}

.desktop-nav a svg,
.login-button svg,
.menu-toggle svg {
  width: 14px;
  height: 14px;
  flex: 0 0 auto;
}

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

.desktop-nav a.active {
  color: var(--color-accent-dark);
  font-weight: 700;
}

.header-tools {
  position: relative;
  display: flex;
  align-items: center;
  gap: 9px;
}

.language-control {
  position: relative;
}

.language-button {
  min-width: 44px;
  min-height: 36px;
  padding: 6px 8px;
  border: 0;
  background: transparent;
  color: var(--color-muted);
  font-size: 13px;
}

.language-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 76;
  display: none;
  width: 156px;
  padding: 6px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  box-shadow: var(--shadow-window);
}

.language-menu.open {
  display: grid;
}

.language-menu a {
  min-height: 40px;
  padding: 8px 10px;
  border-radius: var(--radius-xs);
  color: var(--color-text);
  text-decoration: none;
}

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

.login-button {
  display: inline-flex;
  min-height: 38px;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border: 1.5px solid var(--color-accent);
  border-radius: var(--radius-sm);
  color: var(--color-accent);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
}

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

.menu-toggle {
  display: none;
  width: 44px;
  min-width: 44px;
  height: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
}

.mobile-nav {
  position: fixed;
  top: var(--header-height);
  right: 0;
  left: 0;
  z-index: 74;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 12px var(--gutter) 20px;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-panel);
  box-shadow: var(--shadow-window);
}

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

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 44px;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  color: var(--color-text);
  text-decoration: none;
}

.mobile-nav a svg {
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
}

.mobile-nav a.active,
.mobile-nav a:hover {
  background: var(--color-panel-alt);
}

.mobile-language-list {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--color-border);
}

.nav-veil {
  position: fixed;
  inset: var(--header-height) 0 0;
  z-index: 69;
  display: none;
  border: 0;
  background: rgba(31, 20, 9, .3);
}

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

.site-footer {
  position: relative;
  z-index: 2;
  border-top: 1px solid var(--color-border);
  background: var(--color-panel);
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(240px, 1.25fr) repeat(3, minmax(150px, 1fr));
  gap: 42px;
  padding-top: 58px;
  padding-bottom: 44px;
}

.footer-brand p {
  max-width: 360px;
  margin-top: 16px;
  color: var(--color-muted);
}

.footer-heading {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

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

.footer-links a {
  min-height: 24px;
  color: var(--color-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 14px;
  padding-top: 20px;
  padding-bottom: 24px;
  border-top: 1px solid var(--color-border);
  color: var(--color-muted);
  font-size: 12px;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
}

.footer-legal a {
  color: inherit;
}

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

.prose h2,
.prose h3 {
  scroll-margin-top: var(--toc-offset);
}

.prose p,
.prose li {
  font-size: 16px;
  line-height: 1.85;
}

.prose p {
  margin-bottom: 1.25em;
}

.prose blockquote {
  margin-inline: 0;
}

@media (max-width: 1180px) {
  .desktop-nav {
    display: none;
  }

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

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

@media (max-width: 768px) {
  :root {
    --header-height: 60px;
  }

  h1 {
    font-size: clamp(28px, 9.5vw, 40px);
    line-height: 1.12;
  }

  h2 {
    font-size: clamp(28px, 8vw, 36px);
  }

  .language-control {
    display: none;
  }

  .footer-main {
    grid-template-columns: 1fr 1fr;
    gap: 32px 24px;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

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

@media (max-width: 640px) {
  .no-break {
    white-space: normal;
  }

  .tilted,
  [data-tilt-card] {
    transform: none;
  }

  .header-inner {
    gap: 10px;
  }

  .brand-name {
    font-size: 16px;
  }

  .brand-local {
    display: none;
  }

  .login-button {
    padding-inline: 11px;
  }

  .login-button svg {
    display: none;
  }

  .button-row > a,
  .button-row > button {
    flex: 1 1 150px;
  }

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

  .footer-brand {
    grid-column: auto;
  }
}

@media (max-width: 380px) {
  .brand img {
    width: 28px;
    height: 28px;
  }

  .login-button {
    min-width: 54px;
    padding-inline: 9px;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto;
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }

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