:root {
  color-scheme: light;
  --color-background: #ffffff;
  --color-background-elevated: #f5f5f7;
  --color-text: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-separator: #d2d2d7;
  --color-accent: hsl(var(--accent-hue) 68% 40%);
  --color-accent-strong: hsl(var(--accent-hue) 72% 32%);
  --color-accent-soft: hsl(var(--accent-hue) 60% 96%);
  --color-header-backdrop: rgba(255, 255, 255, 0.72);
  --color-card-shadow: rgba(0, 0, 0, 0.06);
  --radius-large: 18px;
  --radius-medium: 14px;
  --content-width: 64rem;
  --article-width: 43rem;
}

[data-theme="dark"] {
  color-scheme: dark;
  --color-background: #000000;
  --color-background-elevated: #1d1d1f;
  --color-text: #f5f5f7;
  --color-text-secondary: #a1a1a6;
  --color-separator: #3d3d41;
  --color-accent: hsl(var(--accent-hue) 80% 64%);
  --color-accent-strong: hsl(var(--accent-hue) 84% 72%);
  --color-accent-soft: hsl(var(--accent-hue) 45% 14%);
  --color-header-backdrop: rgba(22, 22, 23, 0.72);
  --color-card-shadow: rgba(0, 0, 0, 0.5);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s ease, color 0.3s ease;
}

h1,
h2,
h3 {
  line-height: 1.15;
  letter-spacing: -0.015em;
  font-weight: 700;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

img,
svg {
  max-width: 100%;
  height: auto;
}

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: -999rem;
  top: 0;
  background: var(--color-accent);
  color: #ffffff;
  padding: 0.6rem 1.2rem;
  border-radius: 0 0 12px 12px;
  z-index: 200;
}

.skip-link:focus {
  left: 1rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-header-backdrop);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--color-separator);
}

.site-header-inner {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 3.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--color-text);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
}

.site-brand:hover {
  text-decoration: none;
}

.site-brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.7rem;
  height: 1.7rem;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-strong));
  color: #ffffff;
  font-size: 0.95rem;
  font-weight: 700;
}

.site-navigation {
  display: flex;
  align-items: center;
  gap: 1.9rem;
}

.site-navigation a {
  color: var(--color-text-secondary);
  font-size: 0.92rem;
  transition: color 0.2s ease;
}

.site-navigation a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.site-navigation a.active {
  color: var(--color-text);
  font-weight: 600;
}

.site-header-actions {
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.1rem;
  height: 2.1rem;
  border: 1px solid var(--color-separator);
  border-radius: 50%;
  background: transparent;
  color: var(--color-text);
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--color-text-secondary);
}

.theme-icon-moon {
  display: none;
}

[data-theme="dark"] .theme-icon-sun {
  display: none;
}

[data-theme="dark"] .theme-icon-moon {
  display: block;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 0.4rem;
  width: 2.1rem;
  height: 2.1rem;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  height: 1.5px;
  width: 1.15rem;
  margin: 0 auto;
  background: var(--color-text);
  transition: transform 0.25s ease;
}

main {
  min-height: 60vh;
}

.content-container {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.hero {
  padding: 5.75rem 1.5rem 4.25rem;
  text-align: center;
}

.hero h1 {
  font-size: clamp(2.5rem, 6.5vw, 4.25rem);
  letter-spacing: -0.02em;
  max-width: 22ch;
  margin: 0 auto;
}

.hero p {
  font-size: clamp(1.15rem, 2.2vw, 1.4rem);
  color: var(--color-text-secondary);
  max-width: 42rem;
  margin: 1.4rem auto 0;
}

.hero-actions {
  margin-top: 2.4rem;
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.pill-link {
  display: inline-block;
  padding: 0.75em 1.6em;
  border-radius: 980px;
  background: var(--color-accent);
  color: #ffffff;
  font-size: 0.98rem;
  font-weight: 500;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.pill-link:hover {
  background: var(--color-accent-strong);
  text-decoration: none;
  transform: translateY(-1px);
}

.pill-link-quiet {
  background: var(--color-background-elevated);
  color: var(--color-text);
}

.pill-link-quiet:hover {
  background: var(--color-separator);
}

.section {
  padding: 4.25rem 0;
}

.section-alternate {
  background: var(--color-background-elevated);
}

.section-title {
  font-size: clamp(1.85rem, 4vw, 2.5rem);
  text-align: center;
}

.section-introduction {
  color: var(--color-text-secondary);
  text-align: center;
  max-width: 44rem;
  margin: 1.1rem auto 0;
  font-size: 1.12rem;
}

.article-card {
  display: block;
  margin: 3rem auto 0;
  max-width: 52rem;
  background: var(--color-background-elevated);
  border-radius: var(--radius-large);
  padding: 2.6rem 2.8rem;
  color: var(--color-text);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.section-alternate .article-card {
  background: var(--color-background);
}

.article-card:hover {
  text-decoration: none;
  transform: translateY(-3px);
  box-shadow: 0 18px 40px var(--color-card-shadow);
}

.article-card-label {
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-accent);
}

.article-card h3 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  margin-top: 0.7rem;
}

.article-card p {
  margin-top: 1rem;
  color: var(--color-text-secondary);
  font-size: 1.05rem;
}

.article-card-meta {
  margin-top: 1.5rem;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

.topic-grid {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
}

.topic-card {
  background: var(--color-background-elevated);
  border-radius: var(--radius-medium);
  padding: 1.8rem;
}

.section-alternate .topic-card {
  background: var(--color-background);
}

.topic-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
}

.topic-card p {
  margin-top: 0.6rem;
  color: var(--color-text-secondary);
  font-size: 0.97rem;
}

.principle-list {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
  text-align: center;
}

.principle-list h3 {
  font-size: 1.15rem;
  font-weight: 600;
}

.principle-list p {
  margin-top: 0.6rem;
  color: var(--color-text-secondary);
  font-size: 0.97rem;
}

.page-header {
  padding: 4.75rem 1.5rem 1rem;
  text-align: center;
}

.page-header h1 {
  font-size: clamp(2.2rem, 5vw, 3.25rem);
  letter-spacing: -0.02em;
  max-width: 24ch;
  margin: 0 auto;
}

.page-header p {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 42rem;
  margin: 1.2rem auto 0;
}

.page-body {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 2.5rem 1.5rem 5rem;
}

.page-body-wide {
  max-width: 52rem;
}

.page-body h2 {
  font-size: 1.65rem;
  margin-top: 2.9rem;
}

.page-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 2.1rem;
}

.page-body p {
  margin-top: 1.05rem;
}

.page-body ul,
.page-body ol {
  margin-top: 1.05rem;
  padding-left: 1.4rem;
}

.page-body li {
  margin-top: 0.55rem;
}

.page-body li::marker {
  color: var(--color-text-secondary);
}

.detail-panel {
  background: var(--color-background-elevated);
  border-radius: var(--radius-medium);
  padding: 1.6rem 1.8rem;
  margin-top: 1.6rem;
}

.detail-panel p {
  margin-top: 0.5rem;
}

.detail-panel p:first-child {
  margin-top: 0;
}

.author-profile {
  display: flex;
  gap: 1.6rem;
  align-items: flex-start;
  background: var(--color-background-elevated);
  border-radius: var(--radius-large);
  padding: 2.2rem;
  margin-top: 2.5rem;
}

.author-profile-portrait {
  flex: 0 0 5rem;
  width: 5rem;
  height: 5rem;
}

.author-profile h2 {
  margin-top: 0;
  font-size: 1.45rem;
}

.author-profile-handle {
  color: var(--color-text-secondary);
  font-size: 0.92rem;
  margin-top: 0.15rem;
}

.author-profile p {
  margin-top: 0.9rem;
}

.article-header {
  padding: 4.5rem 1.5rem 0;
  text-align: center;
}

.article-header h1 {
  font-size: clamp(2.1rem, 4.6vw, 3.1rem);
  letter-spacing: -0.02em;
  max-width: 24ch;
  margin: 0 auto;
}

.article-header-summary {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 44rem;
  margin: 1.3rem auto 0;
}

.article-byline {
  margin-top: 2.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.9rem;
  font-size: 0.95rem;
  color: var(--color-text-secondary);
}

.article-byline-portrait {
  width: 2.6rem;
  height: 2.6rem;
  flex: 0 0 2.6rem;
}

.article-byline-details {
  text-align: left;
}

.article-byline-author {
  color: var(--color-text);
  font-weight: 600;
}

.article-body {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 3rem 1.5rem 5rem;
}

.article-body h2 {
  font-size: 1.8rem;
  margin-top: 3.2rem;
  scroll-margin-top: 5rem;
}

.article-body h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-top: 2.2rem;
  scroll-margin-top: 5rem;
}

.article-body p {
  margin-top: 1.1rem;
}

.article-body ul,
.article-body ol {
  margin-top: 1.1rem;
  padding-left: 1.4rem;
}

.article-body li {
  margin-top: 0.6rem;
}

.article-body li::marker {
  color: var(--color-text-secondary);
}

.article-disclosure {
  background: var(--color-accent-soft);
  border-radius: var(--radius-medium);
  padding: 1.4rem 1.7rem;
  font-size: 0.97rem;
}

.article-disclosure p {
  margin-top: 0.5rem;
}

.article-disclosure p:first-child {
  margin-top: 0;
}

.article-note {
  background: var(--color-background-elevated);
  border-radius: var(--radius-medium);
  padding: 1.4rem 1.7rem;
  margin-top: 1.6rem;
}

.article-note p {
  margin-top: 0.5rem;
}

.article-note p:first-child {
  margin-top: 0;
}

.table-of-contents {
  background: var(--color-background-elevated);
  border-radius: var(--radius-medium);
  padding: 1.6rem 1.9rem;
  margin-top: 2.4rem;
}

.table-of-contents p {
  margin-top: 0;
  font-weight: 600;
}

.table-of-contents ol {
  margin-top: 0.8rem;
}

.table-of-contents a {
  color: var(--color-text-secondary);
}

.table-of-contents a:hover {
  color: var(--color-accent);
}

.article-sources {
  margin-top: 3rem;
  padding-top: 1.8rem;
  border-top: 1px solid var(--color-separator);
  font-size: 0.94rem;
  color: var(--color-text-secondary);
}

.article-sources p {
  margin-top: 0.5rem;
}

.error-panel {
  padding: 7rem 1.5rem 8rem;
  text-align: center;
}

.error-panel h1 {
  font-size: clamp(2.4rem, 6vw, 3.75rem);
}

.error-panel p {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 36rem;
  margin: 1.3rem auto 0;
}

.site-footer {
  background: var(--color-background-elevated);
  border-top: 1px solid var(--color-separator);
  font-size: 0.88rem;
  color: var(--color-text-secondary);
}

.site-footer-inner {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 3.25rem 1.5rem 2.5rem;
}

.site-footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.6fr;
  gap: 2.5rem;
}

.site-footer-brand {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
}

.site-footer-about p + p {
  margin-top: 0.7rem;
}

.site-footer-heading {
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 0.75rem;
}

.site-footer-navigation {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.site-footer-navigation a {
  color: var(--color-text-secondary);
}

.site-footer-navigation a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.site-footer-contact p {
  margin-top: 0.55rem;
}

.site-footer-contact p:first-child {
  margin-top: 0;
}

.site-footer-contact a {
  color: var(--color-text-secondary);
  text-decoration: underline;
}

.site-footer-contact a:hover {
  color: var(--color-text);
}

.site-footer-legal {
  margin-top: 2.75rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-separator);
}

.site-footer-legal p + p {
  margin-top: 0.4rem;
}

@media (max-width: 820px) {
  .topic-grid,
  .principle-list {
    grid-template-columns: 1fr;
  }

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

  .article-card {
    padding: 2rem 1.6rem;
  }
}

@media (max-width: 640px) {
  .menu-toggle {
    display: flex;
  }

  .site-navigation {
    display: none;
    position: absolute;
    top: 3.25rem;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--color-background);
    border-bottom: 1px solid var(--color-separator);
    padding: 0.5rem 1.5rem 1rem;
  }

  .site-navigation a {
    width: 100%;
    padding: 0.8rem 0;
    font-size: 1.05rem;
    border-bottom: 1px solid var(--color-separator);
  }

  .site-navigation a:last-child {
    border-bottom: 0;
  }

  .navigation-open .site-navigation {
    display: flex;
  }

  .navigation-open .menu-toggle span:first-child {
    transform: translateY(0.28rem) rotate(45deg);
  }

  .navigation-open .menu-toggle span:last-child {
    transform: translateY(-0.28rem) rotate(-45deg);
  }

  .site-footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .author-profile {
    flex-direction: column;
  }

  .article-byline {
    flex-direction: column;
    gap: 0.7rem;
  }

  .article-byline-details {
    text-align: center;
  }
}

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

  *,
  *::before,
  *::after {
    transition: none !important;
  }
}