/* CSS Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* Dark theme (default) */
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #21262d;
  --bg-hover: #30363d;
  
  --text-primary: #f0f6fc;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;
  
  --accent-primary: #58a6ff;
  --accent-secondary: #7ee787;
  --accent-tertiary: #a371f7;
  
  --border-color: #30363d;
  --border-subtle: #21262d;
  
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
  
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-mono: 'SF Mono', Monaco, Consolas, 'Liberation Mono', monospace;
  
  --max-width: 1200px;
  --section-padding: 80px;
}

[data-theme="light"] {
  --bg-primary: #ffffff;
  --bg-secondary: #f6f8fa;
  --bg-card: #ffffff;
  --bg-hover: #f3f4f6;
  
  --text-primary: #1f2328;
  --text-secondary: #656d76;
  --text-muted: #8c959f;
  
  --accent-primary: #0969da;
  --accent-secondary: #1a7f37;
  --accent-tertiary: #8250df;
  
  --border-color: #d0d7de;
  --border-subtle: #e6e9ef;
  
  --shadow-sm: 0 1px 2px rgba(31, 35, 40, 0.04);
  --shadow-md: 0 4px 12px rgba(31, 35, 40, 0.1);
  --shadow-lg: 0 8px 24px rgba(31, 35, 40, 0.15);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-subtle);
  backdrop-filter: blur(8px);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--accent-primary);
}

.nav-controls {
  display: flex;
  gap: 8px;
  align-items: center;
}

.lang-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 8px 12px;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

.lang-toggle:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--accent-primary);
}

.lang-icon {
  font-size: 1rem;
}

.lang-text {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 8px 12px;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 1.1rem;
  transition: all 0.2s ease;
}

.theme-toggle:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--accent-primary);
}

/* Hero Section */
.hero {
  padding: 100px 0 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
  opacity: 0.7;
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero-equation {
  margin-top: 32px;
  font-family: 'Courier New', monospace;
  font-size: 0.85rem;
  color: var(--text-muted);
  opacity: 0.6;
  min-height: 1.5em;
  letter-spacing: 0.02em;
}

.hero-logo {
  width: 140px;
  height: auto;
  margin-bottom: 24px;
  border-radius: var(--radius-lg);
  background-color: var(--bg-secondary);
  padding: 16px;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-md);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hero-logo:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow-lg);
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.5rem);
  color: var(--text-secondary);
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero-description {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin-bottom: 40px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 32px;
}

.hero-note {
  font-size: 0.95rem;
  color: var(--text-muted);
  max-width: 650px;
  margin: 0 auto;
  padding: 20px;
  background-color: var(--bg-secondary);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--accent-primary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--accent-primary);
  color: var(--bg-primary);
  border-color: var(--accent-primary);
}

.btn-primary:hover {
  background-color: transparent;
  color: var(--accent-primary);
}

.btn-secondary {
  background-color: var(--bg-card);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--bg-hover);
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.btn-accent {
  background-color: var(--accent-tertiary);
  color: var(--bg-primary);
  border-color: var(--accent-tertiary);
}

.btn-accent:hover {
  background-color: transparent;
  color: var(--accent-tertiary);
}

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

.btn-outline:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}

.btn-small {
  padding: 8px 16px;
  font-size: 0.85rem;
}

.btn-disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Section Styles */
section {
  padding: var(--section-padding) 0;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 40px;
  color: var(--text-primary);
  text-align: center;
}

/* Projects */
.projects {
  background-color: var(--bg-secondary);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.project-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all 0.3s ease;
}

.project-card:hover {
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.project-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--accent-primary);
}

.project-subtitle {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-style: italic;
}

.project-description {
  font-size: 0.95rem;
  color: var(--text-primary);
  margin-bottom: 20px;
  line-height: 1.6;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.tag {
  font-size: 0.75rem;
  padding: 4px 10px;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border-radius: 100px;
  font-family: var(--font-mono);
  border: 1px solid var(--border-subtle);
}

/* Clean project action buttons */
.project-links {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  margin-top: 22px;
}

.project-links .btn {
  min-width: 104px;
  min-height: 40px;
  padding: 0 16px;
  font-size: 0.82rem;
  font-weight: 650;
  border-radius: 10px;
}

.project-links .btn-secondary {
  background-color: rgba(88, 166, 255, 0.08);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.project-links .btn-secondary:hover {
  background-color: rgba(88, 166, 255, 0.14);
  color: var(--accent-primary);
  border-color: var(--accent-primary);
}

.project-links .btn-outline {
  background-color: transparent;
  color: var(--text-secondary);
  border-color: var(--border-color);
}

.project-links .btn-outline:hover {
  color: var(--accent-primary);
  border-color: var(--accent-primary);
  background-color: rgba(88, 166, 255, 0.08);
}

.btn-doi {
  background: linear-gradient(135deg, rgba(126, 231, 135, 0.16), rgba(88, 166, 255, 0.10));
  color: var(--accent-secondary);
  border-color: rgba(126, 231, 135, 0.45);
}

.btn-doi:hover {
  background: linear-gradient(135deg, rgba(126, 231, 135, 0.24), rgba(88, 166, 255, 0.16));
  color: var(--accent-secondary);
  border-color: var(--accent-secondary);
  transform: translateY(-1px);
}

/* Clean DOI status badges */
.project-badges {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 16px;
}

.badge-soon {
  font-size: 0.7rem;
  padding: 3px 8px;
  background-color: var(--bg-hover);
  color: var(--text-muted);
  border-radius: 100px;
  font-family: var(--font-mono);
  border: 1px solid var(--border-subtle);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.badge-zenodo {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  width: fit-content;
  font-size: 0.68rem;
  padding: 5px 10px;
  background-color: rgba(126, 231, 135, 0.10);
  color: var(--accent-secondary);
  border-radius: 100px;
  font-family: var(--font-mono);
  border: 1px solid rgba(126, 231, 135, 0.35);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  font-weight: 700;
  line-height: 1;
}

.badge-zenodo::before {
  content: "✓";
  font-family: var(--font-family);
  font-weight: 800;
}

[data-theme="light"] .badge-zenodo {
  background-color: rgba(26, 127, 55, 0.09);
  border-color: rgba(26, 127, 55, 0.35);
  color: #1a7f37;
}

@media (max-width: 768px) {
  .project-links {
    flex-direction: column;
    align-items: stretch;
  }

  .project-links .btn {
    width: 100%;
    max-width: none;
  }

  .project-badges {
    justify-content: flex-start;
  }
}

/* Research */
.research {
  background-color: var(--bg-primary);
}

.research-content {
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

.research-content p {
  margin-bottom: 16px;
  color: var(--text-secondary);
}

.research-content strong {
  color: var(--text-primary);
}

.research-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}

/* Technical Focus */
.focus {
  background-color: var(--bg-secondary);
}

.focus-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  max-width: 900px;
  margin: 0 auto;
}

.focus-badge {
  font-size: 0.9rem;
  padding: 10px 18px;
  background-color: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 100px;
  transition: all 0.2s ease;
}

.focus-badge:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  transform: scale(1.02);
}

/* Ecosystem */
.ecosystem {
  background-color: var(--bg-primary);
}

.ecosystem-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
}

.ecosystem-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  text-align: center;
  transition: all 0.3s ease;
}

.ecosystem-card:hover {
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-md);
}

.ecosystem-card-future {
  opacity: 0.8;
}

.ecosystem-card-future:hover {
  border-color: var(--border-color);
  box-shadow: none;
}

.ecosystem-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.ecosystem-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.ecosystem-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.ecosystem-card a {
  font-size: 0.85rem;
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.ecosystem-card a:hover {
  color: var(--accent-secondary);
  text-decoration: underline;
}

.coming-soon {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-style: italic;
}

/* About */
.about {
  background-color: var(--bg-secondary);
}

.about-content {
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

.about-content p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.7;
}

.about-lang {
  font-size: 0.95rem;
  color: var(--accent-primary);
  font-style: italic;
  margin-top: 24px;
  padding: 12px 20px;
  background-color: var(--bg-card);
  border-radius: var(--radius-md);
  display: inline-block;
  border: 1px solid var(--border-color);
}

.about-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}

/* Services / What I Build */
.services {
  background-color: var(--bg-primary);
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.service-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  transition: all 0.3s ease;
}

.service-item:hover {
  border-color: var(--accent-primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.service-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
  display: block;
}

.service-item h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.service-item p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Proof of Work */
.proof {
  background-color: var(--bg-secondary);
}

.proof-content {
  max-width: 700px;
  margin: 0 auto;
}

.proof-list {
  list-style: none;
  padding: 0;
}

.proof-list li {
  font-size: 1.05rem;
  color: var(--text-secondary);
  padding: 16px 0;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

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

.proof-list li::before {
  content: "✓";
  color: var(--accent-secondary);
  font-weight: bold;
  flex-shrink: 0;
}

.proof-list strong {
  color: var(--text-primary);
}

/* Current Status */
.status {
  background-color: var(--bg-primary);
}

.status-content {
  max-width: 700px;
  margin: 0 auto;
}

.status-list {
  list-style: none;
  padding: 0;
}

.status-list li {
  font-size: 1.05rem;
  color: var(--text-secondary);
  padding: 16px 0;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: flex-start;
  gap: 12px;
  line-height: 1.6;
}

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

.status-list li::before {
  content: "→";
  color: var(--accent-primary);
  font-weight: bold;
  flex-shrink: 0;
}

/* Research Pipeline */
.pipeline {
  margin: 40px 0;
  padding: 28px;
  background-color: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.pipeline h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text-primary);
  text-align: center;
}

.pipeline-flow {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
}

.pipeline-step {
  font-size: 0.85rem;
  padding: 8px 16px;
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-radius: 100px;
  font-weight: 500;
  border: 1px solid var(--border-color);
}

.pipeline-arrow {
  color: var(--accent-primary);
  font-size: 1.2rem;
  font-weight: bold;
}

.pipeline-note {
  font-size: 0.95rem;
  color: var(--text-muted);
  text-align: center;
  line-height: 1.6;
  font-style: italic;
}

/* Contact */
.contact {
  background-color: var(--bg-secondary);
  text-align: center;
}

.contact-text {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto 32px;
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
}

/* Footer */
.footer {
  background-color: var(--bg-primary);
  border-top: 1px solid var(--border-subtle);
  padding: 40px 0;
  text-align: center;
}

.footer p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  :root {
    --section-padding: 60px;
  }
  
  .hero {
    padding: 60px 0 50px;
  }
  
  .hero-logo {
    width: 100px;
    padding: 12px;
    margin-bottom: 20px;
  }
  
  .hero-cta {
    flex-direction: column;
    align-items: center;
  }
  
  .nav-links {
    display: none;
  }
  
  .nav-controls {
    gap: 6px;
  }
  
  .lang-toggle {
    padding: 6px 10px;
  }
  
  .lang-text {
    font-size: 0.75rem;
  }
  
  .theme-toggle {
    padding: 6px 10px;
  }
  
  .btn {
    width: 100%;
    max-width: 280px;
  }
  
  .projects-grid {
    grid-template-columns: 1fr;
  }
  
  .ecosystem-grid {
    grid-template-columns: 1fr;
  }
  
  .services-grid {
    grid-template-columns: 1fr;
  }
  
  .about-links {
    flex-direction: column;
    align-items: center;
  }
  
  .pipeline-flow {
    flex-direction: column;
    gap: 12px;
  }
  
  .pipeline-arrow {
    transform: rotate(90deg);
  }
  
  .research-links,
  .contact-links {
    flex-direction: column;
    align-items: center;
  }
  
  .project-links {
    flex-direction: column;
  }
  
  .project-links .btn {
    width: 100%;
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  .hero-canvas {
    display: none;
  }
  
  .hero-equation {
    display: none;
  }
  
  html {
    scroll-behavior: auto;
  }
}

/* Focus Styles for Accessibility */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

/* Selection */
::selection {
  background-color: var(--accent-primary);
  color: var(--bg-primary);
}