/* Root color variables */
:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #eef0f5;
  --text-primary: #1a1a1a;
  --text-secondary: #666666;
  --text-tertiary: #999999;
  --accent: #0066cc;
  --accent-hover: #0052a3;
  --border: #e0e0e0;
  --shadow: rgba(0, 0, 0, 0.08);
  --shadow-lg: rgba(0, 0, 0, 0.12);
}

[data-theme="dark"] {
  --bg-primary: #1a1a1a;
  --bg-secondary: #242424;
  --bg-tertiary: #2d2d2d;
  --text-primary: #ffffff;
  --text-secondary: #b0b0b0;
  --text-tertiary: #808080;
  --accent: #5599ff;
  --accent-hover: #7cb3ff;
  --border: #3a3a3a;
  --shadow: rgba(0, 0, 0, 0.3);
  --shadow-lg: rgba(0, 0, 0, 0.5);
}

/* Typography */
html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition:
    background-color 0.3s ease,
    color 0.3s ease;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 600;
  line-height: 1.25;
  margin: 0;
}

h1 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
}

h2 {
  font-size: 2.25rem;
  margin-bottom: 1.5rem;
  margin-top: 3rem;
}

h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

h4 {
  font-size: 1.25rem;
}

p {
  margin: 0 0 1rem 0;
  color: var(--text-secondary);
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

/* Layout */
.container {
  max-width: 1150px;
  margin: 0 auto;
  padding: 0 2rem;
}

@media (max-width: 768px) {
  .container {
    padding: 0 1.5rem;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }
}

/* Spacing utilities */
.mt-1 {
  margin-top: 0.5rem;
}
.mt-2 {
  margin-top: 1rem;
}
.mt-3 {
  margin-top: 1.5rem;
}
.mt-4 {
  margin-top: 2rem;
}
.mt-5 {
  margin-top: 2.5rem;
}
.mt-6 {
  margin-top: 3rem;
}

.mb-1 {
  margin-bottom: 0.5rem;
}
.mb-2 {
  margin-bottom: 1rem;
}
.mb-3 {
  margin-bottom: 1.5rem;
}
.mb-4 {
  margin-bottom: 2rem;
}
.mb-5 {
  margin-bottom: 2.5rem;
}
.mb-6 {
  margin-bottom: 3rem;
}

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

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

/* Navigation */
nav {
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color 0.3s ease;
}

.nav-container {
  max-width: 1150px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
  align-items: center;
}

.nav-link {
  color: var(--text-secondary);
  transition: color 0.2s ease;
  font-size: 0.95rem;
}

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

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

.theme-toggle,
.lang-switcher {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  border-radius: 0.375rem;
  transition:
    background-color 0.2s ease,
    color 0.2s ease;
}

.theme-toggle:hover,
.lang-switcher:hover {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
}

.lang-dropdown {
  position: relative;
  display: inline-block;
}

.lang-menu {
  display: none;
  position: absolute;
  right: 0;
  top: 100%;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  min-width: 120px;
  list-style: none;
  margin: 0.5rem 0 0 0;
  padding: 0.5rem 0;
  z-index: 200;
}

.lang-menu.active {
  display: block;
}

.lang-menu li {
  padding: 0;
}

.lang-menu button {
  width: 100%;
  padding: 0.5rem 1rem;
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 0.9rem;
  transition: background-color 0.2s ease;
}

.lang-menu button:hover {
  background-color: var(--bg-tertiary);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .nav-container {
    padding: 1rem;
  }
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.875rem 1.75rem;
  border-radius: 0.375rem;
  border: 1px solid transparent;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  font-size: 1rem;
  text-align: center;
}

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

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

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

.btn-secondary:hover {
  background-color: var(--bg-tertiary);
}

.btn-icon {
  padding: 0.5rem;
  border-radius: 0.375rem;
}

.btn-group {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

@media (max-width: 648px) {
  .btn-group {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}

/* Hero Section */
.hero {
  padding: 6rem 0;
  background-color: var(--bg-primary);
}

.hero-content {
  max-width: 650px;
}

.hero-title {
  line-height: 1.1;
  margin-bottom: 1rem;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.5;
  max-width: 550px;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
}

@media (max-width: 768px) {
  .hero {
    padding: 4rem 0;
  }

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

  .hero-subtitle {
    font-size: 1.1rem;
  }

  .hero-actions {
    flex-direction: column;
  }

  .hero-actions .btn {
    width: 100%;
  }
}

/* Sections */
.section {
  padding: 4rem 0;
  border-bottom: 1px solid var(--border);
}

.section:last-child {
  border-bottom: none;
}

.section-title {
  position: relative;
  padding-bottom: 1rem;
  margin-bottom: 2.5rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
}

/* About Section */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-content p {
  margin-bottom: 1.5rem;
  line-height: 1.8;
}

.about-cta {
  margin-top: 2rem;
}

@media (max-width: 768px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

/* Skills Section */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
}

.skill-category {
  padding: 1.5rem;
  background-color: var(--bg-secondary);
  border-radius: 0.375rem;
  border-left: 3px solid var(--accent);
}

.skill-category h4 {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

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

.skill-item {
  padding: 0.5rem 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* Experience Section */
.experience-timeline {
  position: relative;
  padding-left: 2rem;
}

.experience-item {
  position: relative;
  padding-bottom: 2.5rem;
  margin-bottom: 2rem;
}

.experience-item::before {
  content: "";
  position: absolute;
  left: -2rem;
  top: 0;
  width: 0.75rem;
  height: 0.75rem;
  background-color: var(--accent);
  border-radius: 50%;
  border: 3px solid var(--bg-primary);
}

.experience-item:last-child {
  margin-bottom: 0;
}

.experience-header {
  margin-bottom: 0.5rem;
}

.experience-company {
  font-weight: 600;
  color: var(--text-primary);
  font-size: 1.1rem;
}

.experience-role {
  color: var(--accent);
  font-weight: 500;
}

.experience-duration {
  font-size: 0.9rem;
  color: var(--text-tertiary);
}

.experience-description {
  margin-top: 1rem;
  color: var(--text-secondary);
}

.experience-achievements {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 0 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.experience-achievements li {
  padding: 0.25rem 0 0.25rem 1.5rem;
  position: relative;
}

.experience-achievements li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--accent);
}

/* Projects Section */
.projects-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.projects-nav {
  display: flex;
  gap: 0.5rem;
}

.projects-nav-btn {
  padding: 0.5rem 0.75rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-primary);
  border-radius: 0.375rem;
  cursor: pointer;
  transition: all 0.2s ease;
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  min-height: 40px;
}

.projects-nav-btn:hover:not(:disabled) {
  background-color: var(--accent);
  border-color: var(--accent);
  color: white;
  transform: scale(1.05);
}

.projects-nav-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.projects-slider-container {
  position: relative;
  overflow: hidden;
  width: 100%;
}

.projects-grid {
  display: flex;
  gap: 2rem;
  padding: 0.5rem 0;
  scroll-behavior: smooth;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

@media (max-width: 768px) {
  .project-card {
    width: 280px;
  }

  .projects-nav {
    gap: 0.25rem;
  }

  .projects-nav-btn {
    min-width: 36px;
    min-height: 36px;
    padding: 0.4rem 0.6rem;
  }
}

@media (max-width: 480px) {
  .project-card {
    width: 240px;
  }

  .projects-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .projects-nav {
    align-self: flex-end;
  }
}

.filter-btn {
  padding: 0.5rem 1rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s ease;
  font-size: 0.9rem;
}

.filter-btn.active {
  background-color: var(--accent);
  color: white;
  border-color: var(--accent);
}

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

.filter-btn.active:hover {
  background-color: var(--accent-hover);
  border-color: var(--accent-hover);
}

.project-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  overflow: hidden;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  height: 100%;
  flex-shrink: 0;
  width: 320px;
}

.project-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 12px var(--shadow-lg);
  transform: translateY(-2px);
}

.project-thumbnail {
  width: 100%;
  height: 200px;
  background-color: var(--bg-tertiary);
  object-fit: cover;
  display: block;
}

.project-content {
  padding: 1.5rem;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
}

.project-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  font-size: 0.85rem;
}

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

.project-title {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
}

.project-description {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  flex-grow: 1;
  font-size: 0.95rem;
  line-height: 1.6;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.project-tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background-color: var(--bg-tertiary);
  border-radius: 999px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.project-link {
  display: inline-block;
  color: var(--accent);
  font-weight: 500;
  transition: color 0.2s ease;
}

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

/* Project Detail Page */
.project-detail {
  padding: 3rem 0;
}

.project-detail-header {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.project-detail-title {
  margin-bottom: 1rem;
}

.project-detail-meta {
  display: flex;
  gap: 2rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.project-detail-meta-item {
  display: flex;
  flex-direction: column;
}

.project-detail-meta-label {
  font-size: 0.85rem;
  color: var(--text-tertiary);
  margin-bottom: 0.25rem;
  text-transform: uppercase;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.project-detail-meta-value {
  color: var(--text-primary);
  font-weight: 500;
}

.project-detail-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.project-detail-body {
  font-size: 1rem;
  line-height: 1.8;
  max-width: 800px;
}

.project-detail-body h3 {
  margin-top: 2rem;
  margin-bottom: 1rem;
  font-size: 1.5rem;
}

.project-detail-body h4 {
  margin-top: 1.5rem;
  margin-bottom: 0.75rem;
}

.project-detail-body p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.project-detail-body ul,
.project-detail-body ol {
  margin: 1rem 0 1rem 1.5rem;
  color: var(--text-secondary);
}

.project-detail-body li {
  margin-bottom: 0.5rem;
}

.project-detail-body code {
  background-color: var(--bg-secondary);
  padding: 0.2rem 0.4rem;
  border-radius: 0.25rem;
  font-family: "Monaco", "Courier New", monospace;
  font-size: 0.9em;
  color: var(--accent);
}

.project-detail-body pre {
  background-color: var(--bg-secondary);
  padding: 1rem;
  border-radius: 0.375rem;
  overflow-x: auto;
  margin: 1rem 0;
}

.project-detail-body pre code {
  background-color: transparent;
  color: var(--text-secondary);
  padding: 0;
}

.project-detail-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  overflow: hidden;
}

.project-detail-body table thead {
  background-color: var(--bg-tertiary);
}

.project-detail-body table th {
  padding: 0.75rem;
  text-align: left;
  font-weight: 600;
  color: var(--text-primary);
  border-bottom: 2px solid var(--border);
}

.project-detail-body table td {
  padding: 0.75rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
}

.project-detail-body table tbody tr:last-child td {
  border-bottom: none;
}

.project-breadcrumb {
  margin-bottom: 2rem;
}

.project-breadcrumb a {
  color: var(--accent);
}

.project-nav {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.project-nav-prev,
.project-nav-next {
  flex: 1;
}

.project-nav-next {
  text-align: right;
}

/* Contact Section */
.contact-section {
  text-align: center;
}

.contact-content {
  max-width: 600px;
  margin: 0 auto 2rem;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

.contact-link {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.contact-link-label {
  font-size: 0.85rem;
  color: var(--text-tertiary);
}

.contact-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Footer */
footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  margin-top: 4rem;
}

.footer-container {
  max-width: 1150px;
  margin: 0 auto;
  padding: 0 2rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  align-items: center;
}

.footer-section h4 {
  margin-bottom: 1rem;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-primary);
}

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

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

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

.footer-social {
  display: flex;
  gap: 1.5rem;
}

.footer-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  color: var(--text-secondary);
  transition: all 0.2s ease;
}

.footer-social a:hover {
  background-color: var(--accent);
  border-color: var(--accent);
  color: white;
}

.footer-copyright {
  grid-column: 1 / -1;
  text-align: center;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  color: var(--text-tertiary);
  font-size: 0.85rem;
}

@media (max-width: 768px) {
  .footer-container {
    grid-template-columns: 1fr;
  }

  footer {
    padding: 1.5rem 0;
  }
}

/* No Flash of Unstyled Content */
html:not([data-theme]) {
  display: none;
}

/* Utility classes */
.hidden {
  display: none !important;
}

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.gap-1 {
  gap: 0.5rem;
}
.gap-2 {
  gap: 1rem;
}
.gap-3 {
  gap: 1.5rem;
}
.gap-4 {
  gap: 2rem;
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

.i18n-loading [data-i18n] {
  visibility: hidden;
}