@font-face {
  font-family: "Anthropic Sans";
  src: url("https://assets.claude.ai/Fonts/AnthropicSans-Text-Regular-Static.otf")
    format("opentype");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Anthropic Sans";
  src: url("https://assets.claude.ai/Fonts/AnthropicSans-Text-Medium-Static.otf")
    format("opentype");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Anthropic Sans";
  src: url("https://assets.claude.ai/Fonts/AnthropicSans-Text-Semibold-Static.otf")
    format("opentype");
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Anthropic Serif Display";
  src: url("https://assets.claude.ai/Fonts/AnthropicSerif-Display-Regular-Static.otf")
    format("opentype");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Anthropic Serif Display";
  src: url("https://assets.claude.ai/Fonts/AnthropicSerif-Display-Medium-Static.otf")
    format("opentype");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

/* ─── Design Tokens ─── */

:root {
  --font-sans: "Anthropic Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-heading: "Anthropic Serif Display", Georgia, "Times New Roman", Times, serif;

  --canvas: #f5f5f0;
  --surface: #ffffff;
  --surface-inset: #faf7f2;
  --surface-hover: #edeae4;

  --ink: #1a1a18;
  --ink-secondary: #6b6a68;
  --ink-muted: #9a9893;
  --ink-tertiary: #b0ada6;

  --accent: #5c4a35;
  --accent-hover: #4a3c2b;
  --accent-muted: rgba(92, 74, 53, 0.08);

  --border: rgba(0, 0, 0, 0.1);
  --border-subtle: rgba(0, 0, 0, 0.06);
  --border-softer: rgba(0, 0, 0, 0.04);

  --shadow: 0 1px 3px rgba(45, 42, 38, 0.04);
  --shadow-lg: 0 4px 12px rgba(45, 42, 38, 0.08);

  --space-micro: 4px;
  --space-sm: 8px;
  --space-md: 12px;
  --space-lg: 16px;
  --space-xl: 24px;
  --space-2xl: 28px;
  --space-3xl: 32px;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 10px;
  --radius-pill: 12px;
  --radius-full: 20px;

  --green: #6b8f71;
  --green-dim: rgba(107, 143, 113, 0.08);
  --red: #c47755;
  --red-dim: rgba(196, 119, 85, 0.08);
  --amber: #c4956a;
  --amber-dim: rgba(196, 149, 106, 0.08);
  --blue: #5b7fa6;
  --blue-dim: rgba(91, 127, 166, 0.08);
  --purple: #957b8d;
  --purple-dim: rgba(149, 123, 141, 0.08);
  --teal: #7a9a8e;
  --teal-dim: rgba(122, 154, 142, 0.08);
}

html.dark {
  --canvas: #1a1a18;
  --surface: #252521;
  --surface-inset: #2d2d28;
  --surface-hover: #3a3a34;
  --ink: #e8e6e1;
  --ink-secondary: #a8a69f;
  --ink-muted: #7a7870;
  --ink-tertiary: #5a584f;
  --accent: #c4a882;
  --accent-hover: #d4bc9a;
  --accent-muted: rgba(196, 168, 130, 0.1);
  --border: rgba(255, 255, 255, 0.1);
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-softer: rgba(255, 255, 255, 0.04);
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.3);

  --green: #8aad8f;
  --green-dim: rgba(138, 173, 143, 0.12);
  --red: #d4917a;
  --red-dim: rgba(212, 145, 122, 0.12);
  --amber: #d4ab84;
  --amber-dim: rgba(212, 171, 132, 0.12);
  --blue: #7a9fc6;
  --blue-dim: rgba(122, 159, 198, 0.12);
  --purple: #b59aad;
  --purple-dim: rgba(181, 154, 173, 0.12);
  --teal: #9abaa8;
  --teal-dim: rgba(154, 186, 168, 0.12);
}

/* ─── Reset ─── */

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-sans);
  line-height: 1.55;
  font-size: 13px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background 0.3s, color 0.3s;
}

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

/* ─── Site Shell ─── */

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 24px 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand-name {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 500;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.3px;
}

.brand-name:hover {
  color: var(--accent);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-toggle {
  background: var(--surface-inset);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  padding: 6px 14px;
  font-size: 12px;
  font-weight: 500;
  color: var(--ink-secondary);
  cursor: pointer;
  transition: all 0.15s;
  font-family: inherit;
  display: flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.theme-toggle:hover {
  background: var(--surface-hover);
  color: var(--ink);
  border-color: var(--accent);
}

.nav-hamburger {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 8px;
  cursor: pointer;
  flex-direction: column;
  gap: 4px;
}

.nav-hamburger span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  border-radius: 1px;
  transition: all 0.2s;
}

.site-nav {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border);
  padding: 0 32px;
  background: var(--surface);
  overflow-x: auto;
}

.site-nav-link {
  padding: 12px 16px;
  font-size: 13px;
  font-weight: 500;
  color: var(--ink-muted);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: all 0.15s;
  white-space: nowrap;
}

.site-nav-link:hover {
  color: var(--ink);
  background: var(--surface-hover);
}

.site-nav-link.active {
  color: var(--ink);
  border-bottom-color: var(--accent);
}

/* ─── Content Components ─── */

.page-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 24px 32px;
}

.page-title {
  font-family: var(--font-heading);
  font-size: 26px;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: -0.3px;
  margin: 0 0 8px;
}

.page-subtitle {
  font-size: 14px;
  color: var(--ink-secondary);
  margin: 0 0 24px;
  line-height: 1.5;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}

.content-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: all 0.2s;
  position: relative;
  overflow: hidden;
}

.content-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--card-accent, var(--accent));
}

.content-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  border-color: var(--border-subtle);
}

.content-card .card-title {
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 400;
  color: var(--ink);
  margin: 0 0 8px;
  letter-spacing: -0.2px;
}

.content-card .card-description {
  font-size: 13px;
  color: var(--ink-secondary);
  line-height: 1.55;
  margin: 0 0 16px;
}

.content-card .card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.card-tag {
  font-size: 11px;
  font-weight: 500;
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  background: var(--accent-muted);
  color: var(--accent);
}

/* ─── Empty State ─── */

.empty-state {
  text-align: center;
  padding: 80px 32px;
  color: var(--ink-muted);
}

.empty-state p {
  font-size: 15px;
  margin: 0;
}

/* ─── Repo Card ─── */

a.repo-card {
  text-decoration: none;
  color: inherit;
  display: block;
}

.repo-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  transition: all 0.2s;
}

.repo-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.repo-card .repo-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
}

.repo-card .repo-name:hover {
  text-decoration: underline;
}

.repo-card .repo-desc {
  font-size: 13px;
  color: var(--ink-secondary);
  margin: 8px 0 12px;
  line-height: 1.55;
}

.repo-card .repo-meta {
  display: flex;
  gap: 16px;
  font-size: 12px;
  color: var(--ink-muted);
}

.repo-card .repo-lang {
  display: flex;
  align-items: center;
  gap: 4px;
}

.repo-card .repo-lang::before {
  content: '';
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--lang-color, var(--ink-muted));
}

/* ─── About Page ─── */

.about-content {
  max-width: 640px;
}

.about-content h2 {
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 400;
  color: var(--ink);
  margin: 32px 0 12px;
  letter-spacing: -0.2px;
}

.about-content h2:first-child {
  margin-top: 0;
}

.about-content p {
  font-size: 14px;
  color: var(--ink-secondary);
  line-height: 1.65;
  margin: 0 0 12px;
}

.contact-links {
  display: flex;
  gap: 16px;
  margin-top: 24px;
}

.contact-links a {
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: all 0.15s;
}

.contact-links a:hover {
  background: var(--accent-muted);
  border-color: var(--accent);
}

/* ─── Home Hero ─── */

.home-hero {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 48px 32px;
  text-align: center;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: 32px;
  font-weight: 400;
  color: var(--ink);
  letter-spacing: -0.4px;
  max-width: 640px;
  margin: 0 auto 12px;
  line-height: 1.3;
}

.hero-subtitle {
  font-size: 15px;
  color: var(--ink-secondary);
  max-width: 560px;
  margin: 0 auto 24px;
  line-height: 1.55;
}

.hero-cta {
  display: inline-block;
  background: var(--accent);
  color: #ffffff;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
  padding: 10px 24px;
  border-radius: var(--radius-md);
  transition: background 0.15s;
}

.hero-cta:hover {
  background: var(--accent-hover);
}

/* ─── Home Sections ─── */

.home-section {
  padding: 32px 32px;
  max-width: 1200px;
  margin: 0 auto;
}

.home-section-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 20px;
}

.home-section-title {
  font-family: var(--font-sans);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--ink-muted);
  margin: 0;
}

.home-section-link {
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s;
}

.home-section-link:hover {
  color: var(--accent-hover);
}

/* ─── Image Card ─── */

.image-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: all 0.2s;
}

.image-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.card-image {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  object-position: center top;
  display: block;
  background: var(--surface-inset);
}

.card-body {
  padding: 16px 20px;
}

.card-body .card-title {
  font-family: var(--font-heading);
  font-size: 16px;
  font-weight: 400;
  color: var(--ink);
  margin: 0 0 6px;
  letter-spacing: -0.2px;
}

.card-body .card-description {
  font-size: 13px;
  color: var(--ink-secondary);
  line-height: 1.55;
  margin: 0;
}

/* ─── Research Preview ─── */

.research-preview {
  aspect-ratio: 16 / 9;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.research-stat {
  font-family: var(--font-heading);
  font-size: 28px;
  font-weight: 400;
  color: var(--accent);
  margin: 0;
  line-height: 1.2;
}

.research-stat-label {
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: 6px;
}

.card-body .card-meta {
  font-size: 11px;
  color: var(--ink-muted);
  margin: 0 0 4px;
  font-weight: 500;
}

/* ─── Responsive ─── */

@media (max-width: 768px) {
  .site-header {
    padding: 16px 20px;
  }

  .site-nav {
    display: none;
    flex-direction: column;
    padding: 0;
  }

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

  .site-nav-link {
    padding: 12px 20px;
    border-bottom: none;
    border-left: 2px solid transparent;
  }

  .site-nav-link.active {
    border-bottom: none;
    border-left-color: var(--accent);
  }

  .nav-hamburger {
    display: flex;
  }

  .page-container {
    padding: 20px 16px;
  }

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

  .page-title {
    font-size: 22px;
  }

  .contact-links {
    flex-direction: column;
  }

  .home-hero {
    padding: 32px 20px;
  }

  .hero-title {
    font-size: 24px;
  }

  .hero-subtitle {
    font-size: 14px;
  }

  .home-section {
    padding: 20px 16px;
  }
}