/* 
 * Healthcare AI Research Portal CSS
 * Dr. M. C. Ruseik Rahumath
 * Performance-optimized futuristic design
 */

/* CSS Custom Properties for consistent theming */
:root {
  /* Color Palette - Healthcare Blue + AI Purple + Clean White */
  --primary-blue: #2563eb;
  --secondary-blue: #06b6d4;
  --ai-purple: #7c3aed;
  --ai-neon: #a855f7;
  --healthcare-teal: #0891b2;
  --clean-white: #ffffff;
  --bg-white: #ffffff;
  --bg-primary: #f8fafc;
  --bg-secondary: #f1f5f9;
  --bg-navbar: rgba(255, 255, 255, 0.95);
  --bg-navbar-scrolled: rgba(255, 255, 255, 0.98);
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-body: #333333;
  --text-footer: #ffffff;
  --text-footer-secondary: rgba(255, 255, 255, 0.8);
  --border-light: #e2e8f0;
  --border-medium: #cbd5e1;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--primary-blue), var(--ai-purple));
  --gradient-secondary: linear-gradient(135deg, var(--secondary-blue), var(--healthcare-teal));
  --gradient-accent: linear-gradient(135deg, var(--ai-neon), var(--ai-purple));
  --gradient-subtle: linear-gradient(135deg, rgba(37, 99, 235, 0.05), rgba(124, 58, 237, 0.05));
  
  /* Typography Scale */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 3.75rem;
  
  /* Spacing Scale */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-base: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-glow: 0 0 20px rgba(124, 58, 237, 0.3);
  --shadow-sm-light: 0 1px 2px 0 rgba(255, 255, 255, 0.05);
  --shadow-base-light: 0 1px 3px 0 rgba(255, 255, 255, 0.1), 0 1px 2px 0 rgba(255, 255, 255, 0.06);
  --shadow-md-light: 0 4px 6px -1px rgba(255, 255, 255, 0.1), 0 2px 4px -1px rgba(255, 255, 255, 0.06);
  --shadow-lg-light: 0 10px 15px -3px rgba(255, 255, 255, 0.1), 0 4px 6px -2px rgba(255, 255, 255, 0.05);
  --shadow-xl-light: 0 20px 25px -5px rgba(255, 255, 255, 0.1), 0 10px 10px -5px rgba(255, 255, 255, 0.04);
  
  /* Border Radius */
  --radius-sm: 0.125rem;
  --radius-base: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-2xl: 1rem;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
  
  /* Z-index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  line-height: 1.5;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--clean-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.25;
  margin-bottom: var(--space-4);
}

h1 { font-size: var(--font-size-5xl); }
h2 { font-size: var(--font-size-4xl); }
h3 { font-size: var(--font-size-3xl); }
h4 { font-size: var(--font-size-2xl); }
h5 { font-size: var(--font-size-xl); }
h6 { font-size: var(--font-size-lg); }

p {
  margin-bottom: var(--space-4);
  color: var(--text-secondary);
}

a {
  color: var(--primary-blue);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

/* Utility Classes */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Loading Screen */
#loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

#loading-screen.hidden {
  opacity: 0;
  visibility: hidden;
}

.loading-animation {
  text-align: center;
  color: white;
}

.dna-helix {
  width: 60px;
  height: 60px;
  margin: 0 auto var(--space-4);
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top: 3px solid white;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-navbar);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-light);
  z-index: var(--z-fixed);
  transition: transform var(--transition-base), background-color var(--transition-base);
}

.navbar.scrolled {
  background: var(--bg-navbar-scrolled);
  box-shadow: var(--shadow-md);
}

.navbar.hidden {
  transform: translateY(-100%);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-4) var(--space-6);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo a {
  font-size: var(--font-size-xl);
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav-link {
  font-weight: 500;
  color: var(--text-primary);
  position: relative;
  padding: var(--space-2) 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--transition-base);
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary-blue);
}

.nav-link:hover::after,
.nav-link.active::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: var(--space-1);
  cursor: pointer;
  padding: var(--space-2);
}

.nav-toggle span {
  width: 25px;
  height: 3px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
  transition: all var(--transition-base);
}

/* Hero Section */
.hero {
  position: relative;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-primary);
  overflow: hidden;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

#particles-canvas {
  width: 100%;
  height: 100%;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: white;
  max-width: 800px;
  padding: 0 var(--space-6);
}

.hero-title {
  font-size: var(--font-size-6xl);
  font-weight: 700;
  margin-bottom: var(--space-6);
  opacity: 0;
  animation: slideUpFade 1s ease-out 0.5s forwards;
}

.title-line {
  display: block;
  margin-bottom: var(--space-2);
}

.hero-subtitle {
  font-size: var(--font-size-2xl);
  font-weight: 500;
  margin-bottom: var(--space-4);
  opacity: 0;
  animation: slideUpFade 1s ease-out 0.7s forwards;
}

.hero-description {
  font-size: var(--font-size-lg);
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--space-8);
  opacity: 0;
  animation: slideUpFade 1s ease-out 0.9s forwards;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
  opacity: 0;
  animation: slideUpFade 1s ease-out 1.1s forwards;
}

.stat {
  text-align: center;
}

.stat-number {
  display: block;
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--space-1);
}

.stat-label {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.8);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero-cta {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  opacity: 0;
  animation: slideUpFade 1s ease-out 1.3s forwards;
}

.scroll-indicator {
  position: absolute;
  bottom: var(--space-8);
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  opacity: 0;
  animation: slideUpFade 1s ease-out 1.5s forwards;
}

.scroll-arrow {
  width: 20px;
  height: 20px;
  border: 2px solid rgba(255, 255, 255, 0.8);
  border-top: none;
  border-right: none;
  transform: rotate(-45deg);
  margin: 0 auto var(--space-2);
  animation: bounce 2s infinite;
}

@keyframes slideUpFade {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0) rotate(-45deg);
  }
  40% {
    transform: translateY(-10px) rotate(-45deg);
  }
  60% {
    transform: translateY(-5px) rotate(-45deg);
  }
}

/* Button Styles */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-base);
  font-weight: 500;
  text-decoration: none;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left var(--transition-slow);
}

.btn:hover::before {
  left: 100%;
}

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

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: transparent;
  color: white;
  border-color: rgba(255, 255, 255, 0.5);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.8);
}

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

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

/* Section Styles */
section {
  padding: var(--space-20) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section-title {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  margin-bottom: var(--space-4);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.section-cta {
  text-align: center;
  margin-top: var(--space-12);
}

/* Apps/Projects Section */
.apps-section {
  background: var(--bg-primary);
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-8);
}

.project-card {
  background: var(--bg-white);
  border-radius: var(--radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}

.project-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
}

.project-card:hover::before {
  transform: scaleX(1);
}

.project-image {
  height: 200px;
  position: relative;
  overflow: hidden;
}

.project-placeholder {
  width: 100%;
  height: 100%;
  background: var(--gradient-secondary);
  position: relative;
}

.project-placeholder::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 60px;
  height: 60px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top: 3px solid white;
  animation: spin 2s linear infinite;
}

.project-placeholder.healthcare-ai {
  background: linear-gradient(135deg, var(--primary-blue), var(--healthcare-teal));
}

.project-placeholder.dhis2 {
  background: linear-gradient(135deg, var(--secondary-blue), var(--ai-purple));
}

.project-placeholder.biomedical {
  background: linear-gradient(135deg, var(--ai-neon), var(--primary-blue));
}

.project-placeholder.pulmonary {
  background: linear-gradient(135deg, var(--healthcare-teal), var(--ai-purple));
}

.project-content {
  padding: var(--space-6);
}

.project-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-3);
  color: var(--text-primary);
}

.project-content p {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  line-height: 1.6;
}

.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.tech-tag {
  padding: var(--space-1) var(--space-3);
  background: var(--gradient-subtle);
  color: var(--primary-blue);
  font-size: var(--font-size-sm);
  font-weight: 500;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-light);
}

.project-link {
  display: inline-flex;
  align-items: center;
  color: var(--primary-blue);
  font-weight: 500;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.project-link::after {
  content: '→';
  margin-left: var(--space-2);
  transition: transform var(--transition-fast);
}

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

.project-link:hover::after {
  transform: translateX(4px);
}

/* Blog Section */
.blog-section {
  background: var(--bg-white);
}

.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--space-8);
}

.blog-card {
  background: var(--bg-primary);
  border-radius: var(--radius-2xl);
  padding: var(--space-6);
  border: 1px solid var(--border-light);
  transition: all var(--transition-base);
}

.blog-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.blog-meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.blog-category {
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-full);
}

.blog-category.healthcare-ai {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-blue);
}

.blog-category.research-methods {
  background: rgba(6, 182, 212, 0.1);
  color: var(--secondary-blue);
}

.blog-category.technical {
  background: rgba(124, 58, 237, 0.1);
  color: var(--ai-purple);
}

.blog-date {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
}

.blog-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-3);
  color: var(--text-primary);
}

.blog-excerpt {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  line-height: 1.6;
}

.blog-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.read-time {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
}

.read-more {
  color: var(--primary-blue);
  font-weight: 500;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.read-more:hover {
  color: var(--ai-purple);
}

/* News Section */
.news-section {
  background: var(--bg-primary);
}

.news-timeline {
  max-width: 800px;
  margin: 0 auto;
  position: relative;
}

.news-timeline::before {
  content: '';
  position: absolute;
  left: var(--space-6);
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--gradient-primary);
}

.timeline-item {
  display: flex;
  gap: var(--space-6);
  margin-bottom: var(--space-8);
  position: relative;
}

.timeline-date {
  flex-shrink: 0;
  width: 120px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-muted);
  text-align: right;
  padding-top: var(--space-1);
}

.timeline-content {
  flex-grow: 1;
  background: var(--bg-white);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  position: relative;
}

.timeline-content::before {
  content: '';
  position: absolute;
  left: -8px;
  top: var(--space-4);
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 8px 8px 8px 0;
  border-color: transparent white transparent transparent;
}

.timeline-icon {
  position: absolute;
  left: calc(-1 * var(--space-6) - 2px - var(--space-2));
  top: var(--space-4);
  width: var(--space-4);
  height: var(--space-4);
  border-radius: 50%;
  background: var(--gradient-primary);
}

.timeline-icon.publication {
  background: var(--gradient-primary);
}

.timeline-icon.conference {
  background: var(--gradient-secondary);
}

.timeline-icon.research {
  background: var(--gradient-accent);
}

.timeline-icon.collaboration {
  background: linear-gradient(135deg, var(--success), var(--healthcare-teal));
}

.timeline-content h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
}

.timeline-content p {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-bottom: 0;
  line-height: 1.6;
}

/* About Section */
.about-section {
  background: var(--bg-white);
}

.about-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: var(--space-16);
  align-items: start;
}

.about-left {
  position: sticky;
  top: calc(60px + var(--space-8));
}

.profile-image {
  width: 300px;
  height: 300px;
  margin: 0 auto var(--space-8);
  border-radius: 50%;
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  position: relative;
}

.profile-placeholder {
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  position: relative;
}

.profile-placeholder::before {
  content: '👨‍⚕️';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 4rem;
}

.quick-stats {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.stat-item {
  text-align: center;
  padding: var(--space-4);
  background: var(--gradient-subtle);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
}

.stat-value {
  display: block;
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--primary-blue);
  margin-bottom: var(--space-1);
}

.stat-label {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

.cv-tabs {
  display: flex;
  gap: var(--space-1);
  margin-bottom: var(--space-8);
  background: var(--bg-secondary);
  padding: var(--space-1);
  border-radius: var(--radius-lg);
}

.tab-btn {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tab-btn.active,
.tab-btn:hover {
  background: var(--bg-white);
  color: var(--primary-blue);
  box-shadow: var(--shadow-sm);
}

.tab-content {
  display: none;
  animation: fadeIn var(--transition-base);
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.cv-item {
  padding: var(--space-6);
  background: var(--bg-primary);
  border-radius: var(--radius-xl);
  margin-bottom: var(--space-4);
  border-left: 4px solid var(--primary-blue);
}

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

.cv-item h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
}

.cv-org {
  font-size: var(--font-size-base);
  font-weight: 500;
  color: var(--primary-blue);
  margin-bottom: var(--space-1);
}

.cv-date {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-3);
}

.cv-desc {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-bottom: 0;
  line-height: 1.6;
}

/* Skills Visualization */
.skills-visualization {
  display: grid;
  gap: var(--space-8);
}

.skill-category h5 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
}

.skill-bars {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.skill-bar {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.skill-name {
  flex-shrink: 0;
  width: 100px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-primary);
}

.skill-progress {
  flex-grow: 1;
  height: 8px;
  background: var(--bg-secondary);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.skill-level {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  transition: width 1s ease-out;
  width: 0;
}

/* Publications List */
.publications-list h5 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
}

.publication-item {
  padding: var(--space-4);
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-4);
  border-left: 3px solid var(--primary-blue);
}

.pub-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.pub-authors {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-1);
}

.pub-journal,
.pub-conference {
  font-size: var(--font-size-sm);
  color: var(--primary-blue);
  font-style: italic;
  margin-bottom: 0;
}

/* Contact Section */
.contact-section {
  background: var(--gradient-primary);
  color: white;
}

.contact-section .section-title,
.contact-section .section-subtitle {
  color: white;
}

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-16);
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.contact-item {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.contact-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.2);
  flex-shrink: 0;
}

.contact-icon::before {
  font-size: 1.5rem;
}

.contact-icon.email::before {
  content: '✉️';
}

.contact-icon.linkedin::before {
  content: '💼';
}

.contact-icon.research::before {
  content: '📊';
}

.contact-details h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
  margin-bottom: var(--space-1);
  color: white;
}

.contact-details a {
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.contact-details a:hover {
  color: white;
  text-decoration: underline;
}

/* Contact Form */
.contact-form {
  background: rgba(255, 255, 255, 0.1);
  padding: var(--space-8);
  border-radius: var(--radius-2xl);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.form-group {
  position: relative;
  margin-bottom: var(--space-6);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: var(--space-4) var(--space-4) var(--space-4) 0;
  background: transparent;
  border: none;
  border-bottom: 2px solid rgba(255, 255, 255, 0.3);
  color: white;
  font-size: var(--font-size-base);
  font-family: var(--font-family);
  transition: border-color var(--transition-fast);
  resize: vertical;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-bottom-color: white;
}

.form-group input::placeholder,
.form-group select::placeholder,
.form-group textarea::placeholder {
  color: rgba(255, 255, 255, 0.6);
}

.form-group label {
  position: absolute;
  left: 0;
  top: var(--space-4);
  color: rgba(255, 255, 255, 0.7);
  font-size: var(--font-size-base);
  transition: all var(--transition-fast);
  pointer-events: none;
}

.form-group input:focus + label,
.form-group select:focus + label,
.form-group textarea:focus + label,
.form-group input:not(:placeholder-shown) + label,
.form-group select:not(:placeholder-shown) + label,
.form-group textarea:not(:placeholder-shown) + label {
  top: 0;
  font-size: var(--font-size-sm);
  color: white;
}

.form-group select {
  cursor: pointer;
}

.form-group select option {
  background: var(--primary-blue);
  color: white;
}

/* Footer */
.footer {
  background: var(--text-primary);
  color: var(--text-footer);
  padding: var(--space-8) 0;
}

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

.footer-left p {
  font-size: var(--font-size-sm);
  color: var(--text-footer-secondary);
  margin-bottom: 0;
}

.footer-right {
  display: flex;
  gap: var(--space-6);
}

.footer-right a {
  font-size: var(--font-size-sm);
  color: var(--text-footer-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-right a:hover {
  color: var(--text-footer);
}

/* Responsive Design */
@media (max-width: 1024px) {
  .container {
    padding: 0 var(--space-4);
  }
  
  .hero-stats {
    gap: var(--space-8);
  }
  
  .about-content {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }
  
  .about-left {
    position: static;
    order: 2;
  }
  
  .contact-content {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }
  
  .timeline-item {
    flex-direction: column;
    gap: var(--space-4);
  }
  
  .timeline-date {
    width: auto;
    text-align: left;
  }
  
  .news-timeline::before {
    display: none;
  }
  
  .timeline-content::before {
    display: none;
  }
  
  .timeline-icon {
    position: static;
    margin-bottom: var(--space-2);
  }
}

@media (max-width: 768px) {
  :root {
    --font-size-6xl: 2.5rem;
    --font-size-5xl: 2rem;
    --font-size-4xl: 1.75rem;
    --font-size-3xl: 1.5rem;
  }
  
  .nav-menu {
    position: fixed;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-navbar-scrolled);
    backdrop-filter: blur(10px);
    flex-direction: column;
    gap: 0;
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--border-light);
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: var(--z-fixed);
    min-height: 200px;
  }
  
  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  .nav-link {
    padding: var(--space-3) 0;
    width: 100%;
    text-align: center;
  }
  
  .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(7px, -6px);
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--space-6);
  }
  
  .hero-cta {
    flex-direction: column;
    align-items: center;
  }
  
  .projects-grid {
    grid-template-columns: 1fr;
  }
  
  .blog-grid {
    grid-template-columns: 1fr;
  }
  
  .profile-image {
    width: 200px;
    height: 200px;
  }
  
  .cv-tabs {
    flex-wrap: wrap;
  }
  
  .tab-btn {
    min-width: calc(50% - var(--space-1));
  }
  
  .footer-content {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }
}

@media (max-width: 480px) {
  section {
    padding: var(--space-16) 0;
  }
  
  .container {
    padding: 0 var(--space-3);
  }
  
  .hero {
    padding: 0 var(--space-3);
  }
  
  .hero-title {
    font-size: var(--font-size-4xl);
  }
  
  .quick-stats {
    grid-template-columns: 1fr;
  }
}

/* Reduced motion preferences */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --text-primary: #000000;
    --text-secondary: #333333;
    --border-light: #666666;
    --border-medium: #333333;
  }
}

/* Blog Categories and Filters */
.blog-categories {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
  margin-bottom: var(--space-12);
  flex-wrap: wrap;
}

.category-btn,
.filter-btn {
  padding: var(--space-2) var(--space-4);
  background: transparent;
  border: 2px solid var(--border-light);
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-base);
}

.category-btn.active,
.category-btn:hover,
.filter-btn.active,
.filter-btn:hover {
  background: var(--primary-blue);
  border-color: var(--primary-blue);
  color: white;
}

.news-filters {
  display: flex;
  justify-content: center;
  gap: var(--space-3);
  margin-bottom: var(--space-12);
  flex-wrap: wrap;
}

/* Newsletter Section */
.newsletter-section {
  background: var(--gradient-subtle);
  padding: var(--space-12) var(--space-6);
  border-radius: var(--radius-2xl);
  text-align: center;
  margin-top: var(--space-16);
  border: 1px solid var(--border-light);
}

.newsletter-section h3 {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  margin-bottom: var(--space-3);
  color: var(--text-primary);
}

.newsletter-section p {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--space-6);
}

.newsletter-form {
  display: flex;
  gap: var(--space-3);
  max-width: 500px;
  margin: 0 auto;
}

.newsletter-form input {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-base);
  transition: border-color var(--transition-fast);
}

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

/* Timeline Tags */
.timeline-tags {
  display: flex;
  gap: var(--space-2);
  margin-top: var(--space-4);
  flex-wrap: wrap;
}

.tag {
  padding: var(--space-1) var(--space-3);
  background: var(--gradient-subtle);
  color: var(--primary-blue);
  font-size: var(--font-size-xs);
  font-weight: 500;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-light);
}

/* News Load More */
.news-load-more {
  text-align: center;
  margin-top: var(--space-12);
}

/* Upcoming Events */
.upcoming-events {
  background: var(--bg-primary);
  padding: var(--space-20) 0;
}

.events-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--space-8);
}

.event-card {
  background: var(--bg-white);
  border-radius: var(--radius-2xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
  display: flex;
  gap: var(--space-4);
  transition: all var(--transition-base);
}

.event-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.event-date {
  flex-shrink: 0;
  text-align: center;
  background: var(--gradient-primary);
  color: white;
  border-radius: var(--radius-xl);
  padding: var(--space-4);
  min-width: 80px;
}

.event-month {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
}

.event-day {
  display: block;
  font-size: var(--font-size-3xl);
  font-weight: 700;
  line-height: 1;
}

.event-year {
  display: block;
  font-size: var(--font-size-sm);
  opacity: 0.9;
}

.event-content h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
}

.event-location {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-2);
}

.event-description {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-bottom: var(--space-3);
}

.event-status {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  border-radius: var(--radius-full);
}

.event-status.upcoming {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.event-status.workshop {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-blue);
}

.event-status.academic {
  background: rgba(124, 58, 237, 0.1);
  color: var(--ai-purple);
}

/* About Page Styles */
.profile-overview {
  margin-bottom: var(--space-16);
}

.profile-card {
  background: var(--bg-white);
  border-radius: var(--radius-2xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-lg);
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-8);
  align-items: start;
}

.profile-card .profile-image {
  width: 200px;
  height: 200px;
  margin: 0;
}

.profile-info h2 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--space-2);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.profile-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--primary-blue);
  margin-bottom: var(--space-1);
}

.profile-institution {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--space-6);
}

.profile-highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

.highlight-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--gradient-subtle);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
}

.highlight-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
}

.highlight-text h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
  margin-bottom: var(--space-1);
  color: var(--text-primary);
}

.highlight-text p {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: 0;
}

.profile-contact {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  background: var(--primary-blue);
  color: white;
  text-decoration: none;
  border-radius: var(--radius-lg);
  font-size: var(--font-size-sm);
  font-weight: 500;
  transition: all var(--transition-base);
}

.contact-link:hover {
  background: var(--ai-purple);
  transform: translateY(-2px);
}

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

/* CV Section */
.cv-section {
  background: var(--bg-primary);
  padding: var(--space-20) 0;
}

.cv-navigation {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
  margin-bottom: var(--space-12);
  flex-wrap: wrap;
}

.cv-nav-btn {
  padding: var(--space-3) var(--space-4);
  background: var(--bg-white);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-base);
}

.cv-nav-btn.active,
.cv-nav-btn:hover {
  background: var(--primary-blue);
  border-color: var(--primary-blue);
  color: white;
}

.cv-content {
  display: none;
  background: var(--bg-white);
  border-radius: var(--radius-2xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-lg);
}

.cv-content.active {
  display: block;
  animation: fadeIn var(--transition-base);
}

.cv-header {
  margin-bottom: var(--space-8);
  text-align: center;
}

.cv-header h2 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Summary Content */
.summary-intro {
  font-size: var(--font-size-lg);
  text-align: center;
  margin-bottom: var(--space-8);
  color: var(--text-primary);
}

.summary-points {
  display: grid;
  gap: var(--space-6);
}

.summary-point {
  padding: var(--space-6);
  background: var(--bg-primary);
  border-radius: var(--radius-xl);
  border-left: 4px solid var(--primary-blue);
}

.summary-point h4 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-3);
  color: var(--text-primary);
}

/* Experience Timeline */
.experience-timeline {
  position: relative;
}

.experience-timeline::before {
  content: '';
  position: absolute;
  left: var(--space-6);
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--gradient-primary);
}

.exp-item {
  display: flex;
  gap: var(--space-6);
  margin-bottom: var(--space-8);
  position: relative;
}

.exp-item::before {
  content: '';
  position: absolute;
  left: calc(var(--space-6) - 6px);
  top: var(--space-4);
  width: 12px;
  height: 12px;
  background: var(--primary-blue);
  border-radius: 50%;
  border: 3px solid white;
  box-shadow: var(--shadow-md);
}

.exp-date {
  flex-shrink: 0;
  width: 120px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-muted);
  text-align: right;
  padding-top: var(--space-1);
}

.exp-content {
  flex-grow: 1;
  background: var(--bg-primary);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
}

.exp-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
}

.exp-content h4 {
  font-size: var(--font-size-lg);
  font-weight: 500;
  color: var(--primary-blue);
  margin-bottom: var(--space-1);
}

.exp-location {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-4);
}

.exp-responsibilities {
  list-style: none;
  margin-bottom: 0;
}

.exp-responsibilities li {
  padding-left: var(--space-4);
  margin-bottom: var(--space-2);
  position: relative;
  color: var(--text-secondary);
}

.exp-responsibilities li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--primary-blue);
  font-weight: 600;
}

/* Education List */
.education-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.edu-item {
  display: flex;
  gap: var(--space-6);
  align-items: flex-start;
}

.edu-date {
  flex-shrink: 0;
  width: 120px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-muted);
  text-align: right;
}

.edu-content {
  flex-grow: 1;
  background: var(--bg-primary);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  border-left: 4px solid var(--ai-purple);
}

.edu-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: var(--text-primary);
}

.edu-content h4 {
  font-size: var(--font-size-lg);
  font-weight: 500;
  color: var(--ai-purple);
  margin-bottom: var(--space-2);
}

.edu-specialization,
.edu-grade {
  font-size: var(--font-size-base);
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.edu-details h5,
.edu-achievements h5 {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.edu-details ul,
.edu-achievements ul {
  list-style: none;
  margin-bottom: 0;
}

.edu-details li,
.edu-achievements li {
  padding-left: var(--space-4);
  margin-bottom: var(--space-1);
  position: relative;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
}

.edu-details li::before,
.edu-achievements li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--ai-purple);
  font-weight: 600;
}

/* Skills Grid */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-8);
}

.skill-category {
  background: var(--bg-primary);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
}

.skill-category h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
  text-align: center;
}

.skills-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.skill-item {
  padding: var(--space-4);
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
}

.skill-name {
  display: block;
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.skill-level {
  display: inline-block;
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  border-radius: var(--radius-full);
  margin-bottom: var(--space-2);
}

.skill-level.expert {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.skill-level.advanced {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-blue);
}

.skill-level.intermediate {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}

.skill-level.native {
  background: rgba(124, 58, 237, 0.1);
  color: var(--ai-purple);
}

.skill-cert {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  font-style: italic;
}

/* Research Section */
.research-section {
  margin-bottom: var(--space-8);
}

.research-section h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
  border-bottom: 2px solid var(--border-light);
  padding-bottom: var(--space-2);
}

.publication-item,
.project-item {
  background: var(--bg-primary);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-4);
  border-left: 3px solid var(--primary-blue);
}

.publication-item h4,
.project-item h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.project-details,
.project-team {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-2);
}

.project-team {
  font-style: italic;
}

/* Achievements Grid */
.achievements-grid {
  display: grid;
  gap: var(--space-8);
}

.achievement-category h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
  text-align: center;
}

.achievement-item {
  display: flex;
  gap: var(--space-4);
  background: var(--bg-primary);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-3);
  border-left: 3px solid var(--success);
}

.achievement-year {
  flex-shrink: 0;
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--success);
  width: 60px;
  text-align: center;
}

.achievement-content h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
  margin-bottom: var(--space-1);
  color: var(--text-primary);
}

.achievement-content p {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: 0;
}

/* Personal Interests */
.interests-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-6);
  margin-bottom: var(--space-8);
}

.interest-card {
  background: var(--bg-primary);
  padding: var(--space-6);
  border-radius: var(--radius-2xl);
  text-align: center;
  border: 1px solid var(--border-light);
  transition: all var(--transition-base);
}

.interest-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.interest-icon {
  font-size: 3rem;
  margin-bottom: var(--space-4);
}

.interest-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--space-3);
  color: var(--text-primary);
}

.interest-card p {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-2);
}

.personal-statement {
  background: var(--gradient-subtle);
  padding: var(--space-8);
  border-radius: var(--radius-2xl);
  text-align: center;
  border: 1px solid var(--border-light);
}

.personal-statement h3 {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  margin-bottom: var(--space-4);
  color: var(--text-primary);
}

.personal-statement blockquote {
  font-size: var(--font-size-lg);
  font-style: italic;
  color: var(--text-secondary);
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.8;
  border: none;
}

/* Responsive Design Improvements */
@media (max-width: 1024px) {
  .profile-card {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .profile-highlights {
    grid-template-columns: 1fr;
  }
  
  .cv-navigation {
    gap: var(--space-1);
  }
  
  .cv-nav-btn {
    padding: var(--space-2) var(--space-3);
    font-size: var(--font-size-xs);
  }
  
  .experience-timeline::before {
    display: none;
  }
  
  .exp-item,
  .edu-item {
    flex-direction: column;
    gap: var(--space-3);
  }
  
  .exp-item::before {
    display: none;
  }
  
  .exp-date,
  .edu-date {
    text-align: left;
    width: auto;
  }
}

@media (max-width: 768px) {
  .newsletter-form {
    flex-direction: column;
  }
  
  .events-grid {
    grid-template-columns: 1fr;
  }
  
  .event-card {
    flex-direction: column;
    text-align: center;
  }
  
  .skills-grid {
    grid-template-columns: 1fr;
  }
  
  .interests-grid {
    grid-template-columns: 1fr;
  }
  
  .profile-contact {
    flex-direction: column;
  }
  
  .contact-link {
    justify-content: center;
  }
}

/* Dark mode support (future enhancement) */
@media (prefers-color-scheme: dark) {
  :root {
    --clean-white: #0f172a;
    --bg-white: #1e293b;
    --bg-primary: #1e293b;
    --bg-secondary: #334155;
    --bg-navbar: #0f172a;
    --bg-navbar-scrolled: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --text-body: #f8fafc;
    --text-footer: #0f172a;
    --text-footer-secondary: rgba(15, 23, 42, 0.8);
    --border-light: #334155;
    --border-medium: #475569;
  }
}

/* SPA Router Enhancement Styles */
.page-loader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(255, 255, 255, 0.95);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  backdrop-filter: blur(5px);
}

.page-loader.active {
  display: flex;
}

.loader-content {
  text-align: center;
}

.loader-content .dna-helix {
  width: 48px;
  height: 48px;
  border: 3px solid rgba(37, 99, 235, 0.3);
  border-top: 3px solid var(--primary-blue);
  margin: 0 auto var(--space-4);
}

.loader-content p {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: var(--font-size-sm);
  margin-bottom: 0;
}

/* SPA Content Transitions */
#main-content {
  transition: opacity 0.2s ease-in-out;
}

/* Error Page Styles */
.error-page {
  text-align: center;
  padding: 4rem 2rem;
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.error-page h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.error-page p {
  font-size: 1.125rem;
  margin-bottom: 2rem;
  color: var(--text-secondary);
  max-width: 500px;
}

/* Route Transition Animations */
.route-enter {
  opacity: 0;
  transform: translateY(20px);
}

.route-enter-active {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.route-exit {
  opacity: 1;
  transform: translateY(0);
}

.route-exit-active {
  opacity: 0;
  transform: translateY(-20px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

/* Progress Bar for Loading */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: var(--gradient-primary);
  z-index: 10000;
  transition: width 0.3s ease;
  width: 0%;
}

.progress-bar.active {
  width: 100%;
}

/* Enhanced Navigation Active States for SPA */
.nav-link.spa-active {
  color: var(--primary-blue);
}

.nav-link.spa-active::after {
  transform: scaleX(1);
}

/* Timeline Enhancements for News Page */
.news-timeline {
  position: relative;
}

.timeline-item {
  position: relative;
  padding-left: var(--space-8);
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: var(--space-2);
  width: 12px;
  height: 12px;
  background: var(--primary-blue);
  border-radius: 50%;
  border: 3px solid white;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

.timeline-item:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 5px;
  top: calc(var(--space-2) + 12px);
  width: 2px;
  height: calc(100% - var(--space-2) - 6px);
  background: linear-gradient(to bottom, var(--primary-blue), transparent);
}

/* News and Blog Tag Styles */
.news-tags,
.blog-tags {
  display: flex;
  gap: var(--space-2);
  margin-top: var(--space-3);
  flex-wrap: wrap;
}

.tag {
  padding: var(--space-1) var(--space-3);
  font-size: var(--font-size-xs);
  font-weight: 500;
  border-radius: var(--radius-full);
  border: 1px solid;
}

.tag.publication {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
  border-color: rgba(16, 185, 129, 0.3);
}

.tag.conference {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-blue);
  border-color: rgba(37, 99, 235, 0.3);
}

.tag.research {
  background: rgba(124, 58, 237, 0.1);
  color: var(--ai-purple);
  border-color: rgba(124, 58, 237, 0.3);
}

.tag.presentation {
  background: rgba(6, 182, 212, 0.1);
  color: var(--secondary-blue);
  border-color: rgba(6, 182, 212, 0.3);
}

.tag.statistics {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
  border-color: rgba(245, 158, 11, 0.3);
}

.tag.medical {
  background: rgba(239, 68, 68, 0.1);
  color: var(--error);
  border-color: rgba(239, 68, 68, 0.3);
}

.tag.education {
  background: rgba(168, 85, 247, 0.1);
  color: var(--ai-neon);
  border-color: rgba(168, 85, 247, 0.3);
}

.tag.milestone {
  background: rgba(34, 197, 94, 0.1);
  color: var(--healthcare-teal);
  border-color: rgba(34, 197, 94, 0.3);
}

/* Projects Page Specific Styles */
.collaboration-section {
  background: var(--bg-primary);
  padding: var(--space-20) 0;
}

.collaboration-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-6);
}

.collab-item {
  background: var(--bg-white);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  text-align: center;
  transition: all var(--transition-base);
}

.collab-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.collab-item h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--primary-blue);
  margin-bottom: var(--space-3);
}

.collab-item p {
  color: var(--text-secondary);
  margin-bottom: 0;
}

.project-tech {
  display: flex;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
  flex-wrap: wrap;
}

.project-actions {
  display: flex;
  gap: var(--space-3);
}

.project-actions .btn {
  flex: 1;
  text-align: center;
}

/* Upcoming Events Section for News */
.upcoming-section {
  margin-top: var(--space-16);
  padding-top: var(--space-16);
  border-top: 2px solid var(--border-light);
}

.upcoming-section h2 {
  font-size: var(--font-size-3xl);
  text-align: center;
  margin-bottom: var(--space-8);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.upcoming-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-6);
}

.event-card {
  background: var(--bg-white);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  transition: all var(--transition-base);
}

.event-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.event-date {
  display: inline-block;
  background: var(--gradient-primary);
  color: white;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-sm);
  font-weight: 600;
  margin-bottom: var(--space-3);
}

.event-card h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

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

/* Media Coverage Section */
.media-section {
  margin-top: var(--space-16);
  padding-top: var(--space-16);
  border-top: 2px solid var(--border-light);
}

.media-section h2 {
  font-size: var(--font-size-3xl);
  text-align: center;
  margin-bottom: var(--space-8);
  background: var(--gradient-secondary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--space-6);
}

.media-item {
  background: var(--bg-white);
  padding: var(--space-6);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-light);
  position: relative;
  transition: all var(--transition-base);
}

.media-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.media-item h4 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.media-item p {
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.media-date {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  background: var(--bg-primary);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
}

/* Responsive improvements for SPA */
@media (max-width: 768px) {
  .timeline-item {
    padding-left: var(--space-6);
  }
  
  .timeline-item::before {
    width: 8px;
    height: 8px;
    left: -2px;
  }
  
  .timeline-item:not(:last-child)::after {
    left: 2px;
  }
  
  .project-actions {
    flex-direction: column;
  }
  
  .collaboration-grid {
    grid-template-columns: 1fr;
  }
  
  .upcoming-grid,
  .media-grid {
    grid-template-columns: 1fr;
  }
}

/* Print Styles */
@media print {
  .navbar,
  .page-loader,
  .hero,
  .footer,
  .btn {
    display: none !important;
  }
  
  body {
    font-size: 12pt;
    line-height: 1.4;
  }
  
  h1, h2, h3, h4, h5, h6 {
    page-break-after: avoid;
  }
  
  .cv-content,
  .timeline-item,
  .project-card {
    page-break-inside: avoid;
  }
}
  }
  
  .project-card,
  .blog-card,
  .timeline-content,
  .cv-item,
  .publication-item,
  .event-card,
  .profile-card,
  .cv-content,
  .interest-card {
    background: var(--bg-secondary);
  }
  
  .navbar {
    border-bottom-color: rgba(255, 255, 255, 0.1);
  }
  
  .nav-menu {
    backdrop-filter: none;
  }
}