/* ==========================================================================
   ROTALABS.AI - Minimal Design (Catchme-inspired)
   ========================================================================== */

@font-face {
  font-family: 'Rota';
  src: url('/assets/fonts/rota.woff2') format('woff2');
  font-weight: normal;
  font-style: normal;
  font-display: swap;
}

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

:root {
  --text: #1a1a1a;
  --text-secondary: #525252;
  --text-tertiary: #8a8a8a;
  --border: #e5e5e5;
  --bg: #fafafa;
  --bg-card: #fff;
  --accent: #b509ac;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'IBM Plex Sans', -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text-secondary);
  line-height: 1.65;
  min-height: 100vh;
}

/* --------------------------------------------------------------------------
   Layout
   -------------------------------------------------------------------------- */

.container {
  max-width: 840px;
  margin: 0 auto;
  padding: 0 24px;
}

main.container {
  padding-top: 0;
  padding-bottom: 96px;
}

/* --------------------------------------------------------------------------
   Links
   -------------------------------------------------------------------------- */

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

a:hover {
  text-decoration: underline;
}

.link-arrow::after {
  content: ' →';
}

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */

h1 {
  font-size: clamp(32px, 5vw, 42px);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--text);
  margin-bottom: 24px;
}

h2 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  margin-bottom: 24px;
  border: none;
  padding: 0;
}

h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

h4 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-tertiary);
  margin-top: 24px;
  margin-bottom: 12px;
}

p {
  margin-bottom: 16px;
}

strong {
  color: var(--text);
  font-weight: 500;
}

ul {
  margin: 12px 0;
  padding-left: 24px;
}

li {
  margin-bottom: 8px;
  color: var(--text-secondary);
}

/* --------------------------------------------------------------------------
   Navigation
   -------------------------------------------------------------------------- */

.site-header {
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: 840px;
  margin: 0 auto;
  padding: 0 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.nav-logo:hover {
  text-decoration: none;
}

.logo-rota {
  background: var(--text);
  color: var(--bg);
  padding: 0 6px;
  margin-right: 1px;
  border-radius: 2px;
}

.logo-labs {
  color: var(--text);
  background: #fff;
  padding: 0 6px;
  border-radius: 2px;
}

[data-theme="dark"] .logo-labs {
  background: #000;
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  color: var(--text-tertiary);
}

.nav-links a:hover {
  color: var(--text);
  text-decoration: none;
}

.nav-links a.active {
  color: var(--text);
}

/* Mobile Navigation Toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-tertiary);
}

.nav-toggle:hover {
  color: var(--text);
}

.nav-toggle svg {
  width: 24px;
  height: 24px;
}

.nav-toggle .icon-close {
  display: none;
}

.nav-toggle[aria-expanded="true"] .icon-menu {
  display: none;
}

.nav-toggle[aria-expanded="true"] .icon-close {
  display: block;
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
    order: 2;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 16px 24px 24px;
    gap: 0;
  }

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

  .nav-links li {
    margin: 0;
  }

  .nav-links a {
    display: block;
    padding: 12px 0;
    font-size: 16px;
    border-bottom: 1px solid var(--border);
  }

  .nav-links li:last-child a {
    border-bottom: none;
  }

  .theme-toggle {
    order: 3;
  }

  .site-header {
    position: relative;
  }
}

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */

.hero {
  padding: 120px 0 80px;
  border-bottom: 1px solid var(--border);
  text-align: left;
}

.hero-eyebrow {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-secondary);
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 6px 12px;
  display: inline-block;
  margin-bottom: 32px;
}

.hero h1 {
  margin-bottom: 24px;
}

.hero-description {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 560px;
  margin-bottom: 0;
}

.hero-links {
  margin-top: 32px;
}

.hero-links a {
  font-size: 16px;
}

@media (max-width: 600px) {
  .hero {
    padding: 80px 0 60px;
  }
}

/* --------------------------------------------------------------------------
   Sections
   -------------------------------------------------------------------------- */

section {
  padding: 64px 0;
  border-bottom: 1px solid var(--border);
}

section:first-child {
  padding-top: 64px;
}

section:last-of-type {
  border-bottom: none;
}

section + section {
  border-top: none;
}

.section-link {
  margin-top: 32px;
}

.section-intro {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

@media (max-width: 600px) {
  section {
    padding: 48px 0;
  }
}

/* --------------------------------------------------------------------------
   Page Header
   -------------------------------------------------------------------------- */

.page-header {
  padding: 80px 0 64px;
  border-bottom: 1px solid var(--border);
}

.page-header h1 {
  margin-bottom: 16px;
}

.page-header p {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 560px;
  margin-bottom: 0;
}

/* --------------------------------------------------------------------------
   Stats
   -------------------------------------------------------------------------- */

.stats {
  display: flex;
  gap: 48px;
  padding: 32px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.stat-value {
  font-size: 24px;
  font-weight: 600;
  color: var(--text);
  line-height: 1;
  margin-bottom: 4px;
}

.stat-value.accent {
  color: var(--accent);
}

.stat-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-tertiary);
}

@media (max-width: 600px) {
  .stats {
    flex-direction: column;
    gap: 24px;
  }
}

/* --------------------------------------------------------------------------
   Cards
   -------------------------------------------------------------------------- */

.card,
.paper,
.project,
.research-track,
.post-preview {
  padding: 24px 0;
  border-bottom: 1px solid var(--border);
}

.card:last-child,
.paper:last-child,
.project:last-child,
.research-track:last-child,
.post-preview:last-child {
  border-bottom: none;
}

.card h3,
.paper h3,
.project h3,
.research-track h3 {
  margin-bottom: 8px;
}

.meta {
  font-size: 13px;
  color: var(--text-tertiary);
  margin-bottom: 12px;
}

/* Paper/Project links */
.paper-links a,
.project-links a,
.track-links a,
.person-links a {
  margin-right: 24px;
  font-size: 14px;
}

/* Project stats */
.project-stats {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  color: var(--text-tertiary);
  margin-bottom: 16px;
}

/* --------------------------------------------------------------------------
   Tables
   -------------------------------------------------------------------------- */

table {
  width: 100%;
  font-size: 14px;
  border-collapse: collapse;
  margin: 24px 0;
}

th {
  font-weight: 500;
  text-align: left;
  padding: 12px 0;
  padding-right: 24px;
  border-bottom: 1px solid var(--border);
  color: var(--text-tertiary);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

td {
  padding: 14px 0;
  padding-right: 24px;
  border-bottom: 1px solid #f0f0f0;
  vertical-align: top;
}

tr:last-child td {
  border-bottom: none;
}

td:first-child {
  font-weight: 500;
  color: var(--text);
}

/* --------------------------------------------------------------------------
   Code
   -------------------------------------------------------------------------- */

pre {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 16px;
  overflow-x: auto;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 14px;
  color: var(--text-secondary);
  margin: 16px 0;
}

code {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.9em;
}

p code {
  background: #f0f0f0;
  padding: 2px 6px;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */

.site-footer {
  padding: 64px 0;
  border-top: 1px solid var(--border);
  margin-top: 0;
}

.site-footer .container {
  max-width: 840px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.footer-brand {
  display: flex;
  align-items: center;
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 8px;
}

.footer-brand img {
  width: 24px;
  height: 24px;
}

.footer-tagline {
  font-size: 14px;
  color: var(--text-tertiary);
  margin-bottom: 8px;
}

.footer-copyright {
  font-size: 13px;
  color: var(--text-tertiary);
}

.footer-links {
  display: flex;
  gap: 24px;
}

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

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

.footer-column h4 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text);
  margin-bottom: 16px;
  margin-top: 0;
}

.footer-column ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-column li {
  margin-bottom: 8px;
}

.footer-column a {
  font-size: 14px;
  color: var(--text-tertiary);
}

@media (max-width: 600px) {
  .footer-content {
    flex-direction: column;
    gap: 24px;
  }
}

/* --------------------------------------------------------------------------
   Blog Post
   -------------------------------------------------------------------------- */

.post-header {
  padding: 80px 0 64px;
  border-bottom: 1px solid var(--border);
}

.post-header .meta {
  margin-bottom: 16px;
}

.post-header h1 {
  margin-bottom: 0;
}

.back-link {
  display: inline-block;
  font-size: 14px;
  color: var(--text-tertiary);
  margin-bottom: 32px;
}

.back-link:hover {
  color: var(--text);
}

.post-content {
  padding: 48px 0;
}

.post-content h2 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
  text-transform: none;
  letter-spacing: -0.01em;
  margin-top: 48px;
  margin-bottom: 16px;
}

.post-content p {
  line-height: 1.75;
}

.post-footer {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.post-tags {
  display: flex;
  gap: 8px;
}

.post-entry time {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  color: var(--text-tertiary);
  display: block;
  margin-bottom: 8px;
}

.post-entry h2 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
  text-transform: none;
  letter-spacing: -0.01em;
  margin: 0 0 8px 0;
  padding: 0;
  border: none;
}

.post-entry h2 a {
  color: var(--text);
}

.post-entry h2 a:hover {
  color: var(--accent);
}

.empty-state {
  color: var(--text-tertiary);
  font-style: italic;
}

/* --------------------------------------------------------------------------
   Badge (minimal)
   -------------------------------------------------------------------------- */

.badge {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-tertiary);
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 4px 8px;
  display: inline-block;
}

/* --------------------------------------------------------------------------
   About / Team
   -------------------------------------------------------------------------- */

.team-member {
  margin-bottom: 48px;
}

.team-member h3 {
  margin-bottom: 4px;
}

.team-role {
  font-size: 14px;
  color: var(--text-tertiary);
  margin-bottom: 16px;
}

.team-links {
  display: flex;
  gap: 24px;
  font-size: 14px;
  margin-top: 16px;
}

/* --------------------------------------------------------------------------
   Utilities
   -------------------------------------------------------------------------- */

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

/* --------------------------------------------------------------------------
   Syntax Highlighting
   -------------------------------------------------------------------------- */

.highlight {
  background: var(--bg-card);
  border: 1px solid var(--border);
  margin: 16px 0;
}

.highlight pre {
  margin: 0;
  border: none;
}

.highlight .c { color: var(--text-tertiary); }
.highlight .k { color: #0066cc; }
.highlight .n { color: var(--text-secondary); }
.highlight .s { color: #22863a; }
.highlight .o { color: var(--text-tertiary); }

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */

@media (max-width: 600px) {
  h1 {
    font-size: 28px;
  }

  .page-header {
    padding: 60px 0 48px;
  }
}

/* --------------------------------------------------------------------------
   Dark Mode
   -------------------------------------------------------------------------- */

[data-theme="dark"] {
  --text: #f5f5f5;
  --text-secondary: #d0d0d0;
  --text-tertiary: #999999;
  --border: #4a4a4a;
  --bg: #333333;
  --bg-card: #3d3d3d;
  --accent: #FFC500;
}

[data-theme="dark"] body {
  background: var(--bg);
}

[data-theme="dark"] pre {
  background: var(--bg-card);
  border-color: var(--border);
}

[data-theme="dark"] p code {
  background: #4a4a4a;
  color: #f0f0f0;
}

[data-theme="dark"] .highlight .k { color: #7eb8ff; }
[data-theme="dark"] .highlight .s { color: #7ee07e; }

/* Theme Toggle */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s ease;
}

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

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

.theme-toggle .icon-sun {
  display: none;
}

.theme-toggle .icon-moon {
  display: block;
}

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

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

/* --------------------------------------------------------------------------
   Search Modal
   -------------------------------------------------------------------------- */

.search-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: none;
  align-items: flex-start;
  justify-content: center;
  padding-top: 10vh;
}

.search-modal.open {
  display: flex;
}

.search-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.search-modal-container {
  position: relative;
  width: 100%;
  max-width: 560px;
  margin: 0 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  overflow: hidden;
}

.search-modal-header {
  border-bottom: 1px solid var(--border);
}

.search-modal-input-wrapper {
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 12px;
}

.search-modal-icon {
  width: 20px;
  height: 20px;
  color: var(--text-tertiary);
  flex-shrink: 0;
}

.search-modal-input {
  flex: 1;
  padding: 16px 0;
  font-family: inherit;
  font-size: 16px;
  border: none;
  background: transparent;
  color: var(--text);
  outline: none;
}

.search-modal-input::placeholder {
  color: var(--text-tertiary);
}

.search-modal-kbd {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  padding: 4px 6px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--text-tertiary);
}

.search-modal-results {
  max-height: 400px;
  overflow-y: auto;
}

.search-modal-empty {
  padding: 32px 16px;
  text-align: center;
  color: var(--text-tertiary);
}

.search-modal-empty p {
  margin: 0;
}

.search-modal-hint {
  margin-top: 8px !important;
  font-size: 13px;
}

.search-modal-hint kbd {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  padding: 2px 5px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 3px;
}

.search-modal-list {
  list-style: none;
  padding: 8px;
  margin: 0;
}

.search-modal-item {
  margin: 0;
  border-radius: 6px;
}

.search-modal-item a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  color: var(--text);
  text-decoration: none;
  border-radius: 6px;
}

.search-modal-item:hover a,
.search-modal-item.selected a {
  background: var(--bg);
}

.search-modal-item-icon {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  color: var(--text-tertiary);
}

.search-modal-item-icon svg {
  width: 20px;
  height: 20px;
}

.search-modal-item-content {
  flex: 1;
  min-width: 0;
}

.search-modal-item-title {
  display: block;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.search-modal-item-meta {
  display: block;
  font-size: 13px;
  color: var(--text-tertiary);
  margin-top: 2px;
}

/* Dark mode adjustments */
[data-theme="dark"] .search-modal-backdrop {
  background: rgba(0, 0, 0, 0.5);
}

/* --------------------------------------------------------------------------
   Related Posts
   -------------------------------------------------------------------------- */

.related-posts {
  margin-top: 64px;
  padding-top: 48px;
  border-top: 1px solid var(--border);
}

.related-posts h2 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  margin-bottom: 24px;
}

.related-posts-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.related-posts-list li {
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
  margin: 0;
}

.related-posts-list li:last-child {
  border-bottom: none;
}

.related-posts-list a {
  font-size: 16px;
  color: var(--text);
}

.related-posts-list a:hover {
  color: var(--accent);
  text-decoration: none;
}

.related-post-date {
  display: block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--text-tertiary);
  margin-top: 4px;
}

/* --------------------------------------------------------------------------
   Math (KaTeX)
   -------------------------------------------------------------------------- */

.katex-display {
  margin: 24px 0;
  overflow-x: auto;
  padding: 16px 0;
}

.katex {
  font-size: 1.1em;
}