:root {
  --bg-primary: #1a1a1a;
  --bg-secondary: #252525;
  --bg-card: #2d2d2d;
  --text-primary: #f5f5f5;
  --text-secondary: #a3a3a3;
  --accent: #3380b0;
  /* Blue */
  --accent-hover: #26638a;
  --font-main: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 4rem;
  --border-radius: 8px;
  --transition: all 0.3s ease;
  --nav-height: 70px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-main);
  line-height: 1.6;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

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

ul {
  list-style: none;
}

/* Utilities */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xl);
  text-align: center;
  position: relative;
  padding-bottom: var(--spacing-sm);
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background-color: var(--accent);
  border-radius: 2px;
}

/* Navigation */
.navbar {
  position: sticky;
  top: 0;
  background-color: rgba(26, 26, 26, 0.95);
  backdrop-filter: blur(10px);
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 5%;
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-links a {
  color: var(--text-primary);
  font-weight: 500;
}

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

/* Mobile Menu Toggle (Hidden by default, shown on mobile) */
.menu-toggle {
  display: none;
  font-size: 1.5rem;
  cursor: pointer;
}

/* Sections */
.section-title {
  padding: var(--spacing-xl) 0;
  scroll-margin-top: var(--nav-height);
  margin-top: 50px;
}

/* Hero */
.hero {
  min-height: calc(100vh - var(--nav-height));
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl) 0;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
  align-items: center;
}

.hero-text h1 {
  font-size: 3.5rem;
  margin-bottom: var(--spacing-sm);
}

.hero-text .subtitle {
  font-size: 1.5rem;
  color: var(--accent);
  margin-bottom: var(--spacing-md);
  font-family: var(--font-mono);
}

.hero-text p {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  font-size: 1.1rem;
}

.hero-image {
  display: flex;
  justify-content: center;
}

.hero-image img {
  width: 300px;
  height: 300px;
  object-fit: cover;
  border-radius: 50%;
  border: 4px solid var(--accent);
  box-shadow: 0 0 20px rgba(51, 128, 176, 0.3);
}

.social-links {
  display: flex;
  gap: var(--spacing-md);
}

.social-icon {
  width: 40px;
  height: 40px;
  filter: invert(1);
  /* Make white */
  transition: var(--transition);
}

.social-links a:hover .social-icon {
  filter: sepia(100%) hue-rotate(130deg) saturate(400%);
  /* Tint to accent */
  transform: translateY(-3px);
}

/* Skills Grid */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

.skill-card {
  background-color: var(--bg-card);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  transition: var(--transition);
  border: 1px solid transparent;
}

.skill-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.skill-category {
  color: var(--accent);
  font-family: var(--font-mono);
  margin-bottom: var(--spacing-md);
  font-size: 1.1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding-bottom: var(--spacing-sm);
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.skill-tag {
  background-color: rgba(51, 128, 176, 0.1);
  color: var(--accent);
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
  font-size: 0.9rem;
}

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

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 2px;
  background-color: var(--bg-secondary);
}

.timeline-item {
  position: relative;
  padding-left: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -6px;
  top: 0;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background-color: var(--accent);
  border: 3px solid var(--bg-primary);
}

.timeline-date {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.9rem;
  margin-bottom: var(--spacing-sm);
}

.timeline-content h3 {
  margin-bottom: var(--spacing-xs);
}

.timeline-content .company {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
  font-style: italic;
}

.timeline-content ul {
  list-style-type: disc;
  padding-left: var(--spacing-lg);
  color: var(--text-secondary);
}

.timeline-content li {
  margin-bottom: var(--spacing-sm);
}

/* Education & Achievements Grid */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

.info-card {
  background-color: var(--bg-card);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  height: 100%;
}

.info-card h3 {
  color: var(--accent);
  font-size: 1.2rem;
}

.info-card .year {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-sm);
  display: block;
}

/* Achievements List */
.achievements-list {
  display: grid;
  gap: var(--spacing-md);
}

.achievement-item {
  background-color: var(--bg-card);
  padding: var(--spacing-md);
  border-radius: var(--border-radius);
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.achievement-item:hover {
  background-color: var(--bg-secondary);
  transform: translateX(5px);
}

.achievement-org {
  font-weight: bold;
  color: var(--accent);
  text-align: right;
  margin-left: var(--spacing-md);
}

/* Footer */
footer {
  text-align: center;
  padding: var(--spacing-xl) 0;
  color: var(--text-secondary);
  border-top: 1px solid var(--bg-secondary);
  margin-top: var(--spacing-xl);
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--bg-secondary);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent);
}

/* Mobile Responsive */
@media (max-width: 768px) {
  .navbar {
    justify-content: flex-end;
  }

  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
    flex-direction: column-reverse;
  }

  .hero-image {
    margin-bottom: var(--spacing-lg);
  }

  .hero-text h1 {
    font-size: 2.5rem;
  }

  .nav-links {
    display: none;
    /* Simplification for now, or toggle */
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background-color: var(--bg-primary);
    flex-direction: column;
    padding: var(--spacing-lg);
    text-align: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }

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

  .menu-toggle {
    display: block;
    color: var(--text-primary);
  }

  .social-links {
    justify-content: center;
  }

  .timeline::before {
    left: 10px;
  }

  .timeline-item {
    padding-left: 30px;
  }
  
  .timeline-item::before {
      left: 3px;
  }

  .achievement-item {
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-sm);
  }
  
  .achievement-org {
      text-align: center;
      margin-left: 0;
  }
}