:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f5f5f5;
  --bg-card: #ffffff;
  --text-primary: #1a1a1a;
  --text-secondary: #666666;
  --accent-primary: #2563eb;
  --accent-hover: #1d4ed8;
  --border-color: #e5e5e5;
  --shadow: rgba(0, 0, 0, 0.1);
  --error-bg: #fee;
  --error-border: #fcc;
  --error-text: #c33;
}

[data-theme="dark"] {
  --bg-primary: #1a1a1a;
  --bg-secondary: #2d2d2d;
  --bg-card: #2d2d2d;
  --text-primary: #f5f5f5;
  --text-secondary: #b3b3b3;
  --accent-primary: #3b82f6;
  --accent-hover: #60a5fa;
  --border-color: #404040;
  --shadow: rgba(0, 0, 0, 0.3);
  --error-bg: #3d1a1a;
  --error-border: #5a2424;
  --error-text: #ff6b6b;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  transition: background-color 0.3s ease, color 0.3s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.navbar {
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
  box-shadow: 0 2px 4px var(--shadow);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-primary);
  text-decoration: none;
  transition: color 0.3s ease;
}

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

.nav-link-btn {
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 1rem;
  font-family: inherit;
  padding: 0;
  transition: color 0.3s ease;
}

.nav-link-btn:hover {
  color: var(--accent-primary);
}

.nav-user-info {
  color: var(--text-primary);
  font-weight: 600;
  padding: 0.5rem 1rem;
  background-color: var(--bg-secondary);
  border-radius: 0.5rem;
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.2rem;
  padding: 0.5rem;
  border-radius: 0.5rem;
  transition: background-color 0.3s ease;
}

.theme-toggle:hover {
  background-color: var(--bg-secondary);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
  flex: 1;
}

.hero {
  text-align: center;
  padding: 3rem 0;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.hero-description {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.welcome-message {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 1rem;
  margin: 2rem 0;
  text-align: center;
}

.services-section, .projects-section, .contact-links {
  margin: 3rem 0;
}

.services-section h2, .projects-section h2, .contact-links h2, .portfolio-header h1 {
  margin-bottom: 2rem;
  color: var(--text-primary);
}

.services-grid, .projects-grid, .links-grid {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  align-items: center;
}

.service-card, .project-card, .contact-card {
  width: 100%;
  max-width: 800px;
}

.service-card, .project-card, .contact-card, .info-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 1.5rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  box-shadow: 0 2px 8px var(--shadow);
}

.service-card:hover, .project-card:hover, .contact-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px var(--shadow);
}

.service-card h3, .project-card h3, .contact-card h3, .info-card h2 {
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.service-description, .project-description {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.service-link, .project-link {
  display: inline-block;
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 600;
  transition: color 0.3s ease;
}

.service-link:hover, .project-link:hover {
  color: var(--accent-hover);
}

.contact-card {
  text-decoration: none;
  color: var(--text-primary);
}

.sitemap-header {
  text-align: center;
  padding: 3rem 0 2rem;
}

.sitemap-header h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.sitemap-header p {
  color: var(--text-secondary);
  font-size: 1.125rem;
}

.sitemap-section {
  margin-bottom: 3rem;
}

.sitemap-section h2 {
  font-size: 1.75rem;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.5rem;
}

.sitemap-grid {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  align-items: center;
}

.sitemap-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 1.5rem;
  width: 100%;
  max-width: 800px;
  box-shadow: 0 2px 8px var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.sitemap-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px var(--shadow);
}

.sitemap-card h3 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.sitemap-card h3 a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: color 0.3s ease;
}

.sitemap-card h3 a:hover {
  color: var(--accent-hover);
}

.sitemap-card p {
  color: var(--text-secondary);
  margin: 0;
}

.contact-card p {
  color: var(--text-secondary);
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.tech-tag {
  background-color: var(--accent-primary);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 1rem;
  font-size: 0.875rem;
  font-weight: 500;
}

.portfolio-header {
  text-align: center;
  margin-bottom: 3rem;
}

.portfolio-header p {
  color: var(--text-secondary);
  font-size: 1.125rem;
}

.empty-state {
  text-align: center;
  color: var(--text-secondary);
  padding: 2rem;
  background-color: var(--bg-secondary);
  border-radius: 0.5rem;
}

.auth-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: calc(100vh - 300px);
}

.auth-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 2rem;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 4px 16px var(--shadow);
}

.auth-card h1 {
  margin-bottom: 1.5rem;
  text-align: center;
  color: var(--text-primary);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-weight: 500;
}

.form-group input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 1rem;
  transition: border-color 0.3s ease;
}

.form-group input:focus {
  outline: none;
  border-color: var(--accent-primary);
}

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 0.375rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.3s ease, transform 0.2s ease;
  text-decoration: none;
  display: inline-block;
}

.btn-primary {
  background-color: var(--accent-primary);
  color: white;
  width: 100%;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  transform: translateY(-2px);
}

.btn-secondary {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--border-color);
  transform: translateY(-2px);
}

.btn-danger {
  background-color: #dc2626;
  color: white;
}

.btn-danger:hover {
  background-color: #b91c1c;
  transform: translateY(-2px);
}

.action-buttons {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1rem;
}

.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  align-items: center;
  justify-content: center;
}

.modal-content {
  background-color: var(--bg-card);
  padding: 2rem;
  border-radius: 0.5rem;
  max-width: 500px;
  width: 90%;
  box-shadow: 0 4px 16px var(--shadow);
}

.modal-content h2 {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.modal-content p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.modal-actions {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
  justify-content: flex-end;
}

.error-message {
  background-color: var(--error-bg);
  border: 1px solid var(--error-border);
  color: var(--error-text);
  padding: 1rem;
  border-radius: 0.375rem;
  margin-bottom: 1rem;
}

.auth-link {
  text-align: center;
  margin-top: 1.5rem;
  color: var(--text-secondary);
}

.auth-link a {
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 600;
}

.auth-link a:hover {
  color: var(--accent-hover);
}

.protected-content {
  max-width: 800px;
  margin: 0 auto;
}

.protected-content h1 {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.info-card {
  margin: 2rem 0;
}

.info-card ul {
  margin-left: 2rem;
  color: var(--text-secondary);
}

.error-container {
  text-align: center;
  padding: 4rem 2rem;
}

.error-code {
  font-size: 6rem;
  color: var(--accent-primary);
  margin-bottom: 1rem;
}

.error-container h2 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.error-container p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.error-details {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 1rem;
  margin: 2rem auto;
  max-width: 600px;
  text-align: left;
}

.info-grid {
  display: grid;
  gap: 1rem;
  margin-top: 1rem;
}

.info-item {
  display: flex;
  justify-content: space-between;
  padding: 1rem;
  background-color: var(--bg-secondary);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
}

.info-item strong {
  color: var(--text-primary);
}

.info-item span {
  color: var(--text-secondary);
}

.link-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.footer {
  background-color: var(--bg-card);
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  margin-top: auto;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  text-align: center;
  color: var(--text-secondary);
}

@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .services-grid, .projects-grid, .links-grid {
    grid-template-columns: 1fr;
  }

  .container {
    padding: 1rem;
  }

  .error-code {
    font-size: 4rem;
  }
}