/* CSS Variables - Dark Mode (Default) */
:root {
  --color-bg: #0a0a0b;
  --color-bg-secondary: #111113;
  --color-bg-tertiary: #1a1a1d;
  --color-text: #e4e4e7;
  --color-text-secondary: #a1a1aa;
  --color-text-muted: #71717a;
  --color-primary: #3b82f6;
  --color-primary-hover: #60a5fa;
  --color-accent: #8b5cf6;
  --color-border: #27272a;
  --color-navbar-bg: rgba(10, 10, 11, 0.8);
  --color-navbar-bg-solid: rgba(10, 10, 11, 0.95);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
}

/* Light Mode */
[data-theme="light"] {
  --color-bg: #ffffff;
  --color-bg-secondary: #f8fafc;
  --color-bg-tertiary: #f1f5f9;
  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;
  --color-primary: #2563eb;
  --color-primary-hover: #3b82f6;
  --color-accent: #7c3aed;
  --color-border: #e2e8f0;
  --color-navbar-bg: rgba(255, 255, 255, 0.8);
  --color-navbar-bg-solid: rgba(255, 255, 255, 0.95);
}

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

html {
  scroll-behavior: smooth;
}

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

/* Smooth transitions for theme change */
.navbar,
.hero,
.section,
.timeline-content,
.skill-category,
.project-card,
.contact-card,
.hero-social a,
.hero-avatar,
.btn,
.footer {
  transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease, box-shadow 0.3s ease;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-navbar-bg);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: background 0.3s ease;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav-logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-menu a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: var(--transition);
}

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

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  background: var(--color-primary);
  color: white !important;
  border-radius: 8px;
  cursor: pointer;
}

.nav-cta .btn-arrow {
  width: 16px;
  height: 16px;
  transition: transform 0.3s ease;
}

.nav-cta:hover {
  background: var(--color-primary-hover);
}

.nav-cta:hover .btn-arrow {
  transform: translateX(4px);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 5px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: var(--transition);
}

/* Theme Toggle */
.theme-toggle {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  cursor: pointer;
  transition: var(--transition);
  margin-left: 8px;
}

.theme-toggle:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  color: var(--color-text-secondary);
  transition: var(--transition);
}

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

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  position: absolute;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.theme-toggle .icon-sun {
  opacity: 0;
  transform: rotate(-90deg) scale(0);
}

.theme-toggle .icon-moon {
  opacity: 1;
  transform: rotate(0) scale(1);
}

[data-theme="light"] .theme-toggle .icon-sun {
  opacity: 1;
  transform: rotate(0) scale(1);
}

[data-theme="light"] .theme-toggle .icon-moon {
  opacity: 0;
  transform: rotate(90deg) scale(0);
}

/* Hero */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 120px 24px 80px;
  position: relative;
  background: radial-gradient(ellipse at top, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
}

[data-theme="light"] .hero {
  background: radial-gradient(ellipse at top, rgba(37, 99, 235, 0.08) 0%, transparent 50%);
}

.hero-content {
  max-width: 720px;
  text-align: center;
}

.hero-greeting {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-primary);
  margin-bottom: 16px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.hero-title {
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 3vw, 1.4rem);
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.hero-description {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  max-width: 540px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero-cta {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 48px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 10px;
  transition: var(--transition);
  cursor: pointer;
  border: none;
}

.btn-arrow {
  width: 18px;
  height: 18px;
  transition: transform 0.3s ease;
}

.btn:hover .btn-arrow {
  transform: translateX(4px);
}

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

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

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

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

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

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

.btn-outline .btn-arrow {
  transition: transform 0.3s ease;
}

.btn-outline:hover .btn-arrow {
  transform: translateY(3px);
}

.btn-large {
  padding: 18px 36px;
  font-size: 1rem;
}

.hero-social {
  display: flex;
  gap: 20px;
  justify-content: center;
}

.hero-social a {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  transition: var(--transition);
  cursor: pointer;
}

.hero-social a:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
  transform: translateY(-3px);
}

.hero-social svg {
  width: 20px;
  height: 20px;
}

/* Hero Avatar */
.hero-avatar {
  width: 160px;
  height: 160px;
  margin: 0 auto 32px;
  border-radius: 50%;
  overflow: hidden;
  border: 3px solid var(--color-border);
  box-shadow: 0 0 40px rgba(59, 130, 246, 0.2);
  transition: var(--transition);
}

.hero-avatar:hover {
  border-color: var(--color-primary);
  transform: scale(1.05);
  box-shadow: 0 0 60px rgba(59, 130, 246, 0.3);
}

.hero-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-scroll {
  position: absolute;
  bottom: -20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
}

.scroll-indicator {
  width: 24px;
  height: 40px;
  border: 2px solid var(--color-border);
  border-radius: 12px;
  position: relative;
}

.scroll-indicator::after {
  content: '';
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  background: var(--color-primary);
  border-radius: 2px;
  animation: scroll 2s ease-in-out infinite;
}

@keyframes scroll {
  0%, 100% { opacity: 1; top: 8px; }
  50% { opacity: 0.5; top: 20px; }
}

/* Sections */
.section {
  padding: 120px 0;
}

.section-title {
  font-size: clamp(1.8rem, 5vw, 2.5rem);
  font-weight: 700;
  text-align: center;
  margin-bottom: 64px;
  letter-spacing: -0.02em;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -16px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: var(--color-primary);
  border-radius: 2px;
}

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

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

.about-text p {
  font-size: 1.1rem;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
  line-height: 1.8;
}

.about-text strong {
  color: var(--color-text);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 48px;
  padding-top: 48px;
  border-top: 1px solid var(--color-border);
}

.stat {
  text-align: center;
}

.stat-number {
  display: block;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Experience Timeline */
.timeline {
  max-width: 800px;
  margin: 0 auto;
  position: relative;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--color-border);
}

.timeline-item {
  position: relative;
  padding-left: 40px;
  padding-bottom: 48px;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-marker {
  position: absolute;
  left: -5px;
  top: 6px;
  width: 12px;
  height: 12px;
  background: var(--color-primary);
  border-radius: 50%;
  border: 2px solid var(--color-bg);
}

.timeline-content {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 24px;
  transition: var(--transition);
}

.timeline-content:hover {
  border-color: var(--color-primary);
  transform: translateX(8px);
}

.timeline-header {
  margin-bottom: 8px;
}

.timeline-header h3 {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 4px;
}

.timeline-company {
  font-size: 0.95rem;
  color: var(--color-primary);
}

.timeline-date {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  display: block;
  margin-bottom: 16px;
}

.timeline-description {
  list-style: disc;
  padding-left: 20px;
  margin-bottom: 16px;
}

.timeline-description li {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
  line-height: 1.6;
}

.timeline-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.timeline-tech span {
  font-size: 0.75rem;
  padding: 4px 12px;
  background: var(--color-bg-tertiary);
  color: var(--color-text-muted);
  border-radius: 20px;
  border: 1px solid var(--color-border);
}

/* Skills */
.skills {
  background: var(--color-bg-secondary);
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.skill-category {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 32px;
  text-align: center;
  transition: var(--transition);
}

.skill-category:hover {
  border-color: var(--color-primary);
  transform: translateY(-4px);
}

.skill-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
}

.skill-icon svg {
  width: 28px;
  height: 28px;
  color: white;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
}

.skill-category h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-text);
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
}

.skill-tags span {
  font-size: 0.8rem;
  padding: 6px 14px;
  background: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  border-radius: 20px;
  border: 1px solid var(--color-border);
}

/* Projects */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.project-card {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  overflow: hidden;
  transition: var(--transition);
}

.project-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-8px);
}

.project-card.featured {
  grid-column: span 2;
  display: grid;
  grid-template-columns: 1fr 1.5fr;
}

.project-image {
  aspect-ratio: 16 / 10;
  background: linear-gradient(135deg, var(--color-bg-tertiary), var(--color-bg));
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  overflow: hidden;
}

.project-image img {
  max-width: 80%;
  max-height: 80%;
  object-fit: contain;
  transition: var(--transition);
}

.project-card:hover .project-image img {
  transform: scale(1.1);
}

.project-card.featured .project-image {
  aspect-ratio: auto;
  min-height: 200px;
}

.project-placeholder {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-text-muted);
  opacity: 0.5;
}

.project-content {
  padding: 24px;
}

.project-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
  display: block;
}

.project-content h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

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

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.project-tech span {
  font-size: 0.75rem;
  padding: 4px 12px;
  background: var(--color-bg-tertiary);
  color: var(--color-text-muted);
  border-radius: 20px;
}

.project-links {
  display: flex;
  gap: 16px;
}

.project-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  transition: var(--transition);
  cursor: pointer;
}

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

.project-link svg {
  width: 18px;
  height: 18px;
}

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

.contact-content {
  max-width: 1000px;
  margin: 0 auto;
  text-align: center;
}

.contact-intro {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  margin-bottom: 48px;
  line-height: 1.7;
}

.contact-methods {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.contact-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
}

.contact-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-4px);
}

.contact-icon {
  width: 56px;
  height: 56px;
  background: var(--color-bg-tertiary);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.contact-icon svg {
  width: 24px;
  height: 24px;
  color: var(--color-primary);
}

.contact-label {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.contact-value {
  font-size: 0.95rem;
  color: var(--color-text);
  font-weight: 500;
  white-space: nowrap;
}

/* Footer */
.footer {
  padding: 48px 0;
  text-align: center;
  border-top: 1px solid var(--color-border);
}

.footer p {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 8px;
}

.footer-location {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  opacity: 0.7;
}

/* Responsive */
@media (max-width: 1024px) {
  .skills-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .projects-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .project-card.featured {
    grid-column: span 2;
    grid-template-columns: 1fr;
  }
}

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

  .nav-toggle {
    order: 3;
  }

  .nav-menu {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
  }

  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .nav-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hero-cta {
    flex-direction: column;
    gap: 12px;
  }

  .about-stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .timeline::before {
    left: 6px;
  }

  .timeline-item {
    padding-left: 32px;
  }

  .timeline-marker {
    left: 0;
  }

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

  .project-card.featured {
    grid-column: span 1;
  }

  .contact-methods {
    grid-template-columns: repeat(2, 1fr);
  }

  .section {
    padding: 80px 0;
  }

  .hero-scroll {
    display: none;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .about-stats {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .stat-number {
    font-size: 2rem;
  }

  .contact-methods {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .contact-card {
    padding: 24px 20px;
  }

  .contact-value {
    white-space: normal;
    word-break: break-word;
  }
}