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

body {
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
  color: #333;
  overflow-x: hidden;
}

html {
  scroll-behavior: smooth;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  transition: all 0.3s ease;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.nav-logo h2 {
  color: #2563eb;
  font-weight: 600;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-link {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

.nav-link:hover {
  color: #2563eb;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: #2563eb;
  transition: width 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
}

/* Hamburger Menu */
.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
}

.bar {
  width: 25px;
  height: 3px;
  background: #333;
  margin: 3px 0;
  transition: 0.3s;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
  opacity: 0.3;
}

.hero-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  position: relative;
  z-index: 2;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.highlight {
  background: linear-gradient(45deg, #ffd700, #ffed4e);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: 1.2rem;
  opacity: 0.9;
  margin-bottom: 2rem;
  line-height: 1.7;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
}

.btn {
  padding: 12px 30px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  display: inline-block;
}

.btn-primary {
  background: white;
  color: #2563eb;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.btn-secondary {
  background: transparent;
  color: white;
  border: 2px solid white;
}

.btn-secondary:hover {
  background: white;
  color: #2563eb;
}

/* Globe Animation */
.globe-container {
  position: relative;
  width: 400px;
  height: 400px;
  margin: 0 auto;
}

.globe {
  width: 200px;
  height: 200px;
  background: linear-gradient(45deg, #4299e1, #3182ce);
  border-radius: 50%;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  animation: float 6s ease-in-out infinite;
  box-shadow: 0 0 50px rgba(66, 153, 225, 0.3);
}

.globe::before {
  content: '';
  position: absolute;
  top: 20%;
  left: 20%;
  width: 60%;
  height: 60%;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><path d="M20,20 Q50,10 80,20 Q90,50 80,80 Q50,90 20,80 Q10,50 20,20" fill="none" stroke="rgba(255,255,255,0.3)" stroke-width="1"/></svg>');
  opacity: 0.7;
}

.orbit {
  position: absolute;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.orbit-1 {
  width: 300px;
  height: 300px;
  animation: rotate 20s linear infinite;
}

.orbit-2 {
  width: 350px;
  height: 350px;
  animation: rotate 30s linear infinite reverse;
}

.data-point {
  position: absolute;
  width: 8px;
  height: 8px;
  background: #ffd700;
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

.point-1 {
  top: 20%;
  left: 60%;
  animation-delay: 0s;
}

.point-2 {
  bottom: 30%;
  right: 20%;
  animation-delay: 1s;
}

.point-3 {
  top: 60%;
  left: 20%;
  animation-delay: 2s;
}

/* Sections */
.section-title {
  text-align: center;
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 3rem;
  color: #1a202c;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(45deg, #2563eb, #3b82f6);
  border-radius: 2px;
}

/* About Section */
.about {
  padding: 6rem 0;
  background: #f8fafc;
}

.about-text p {
  font-size: 1.1rem;
  line-height: 1.8;
  margin-bottom: 1.5rem;
  color: #4a5568;
}

.expertise-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.expertise-item {
  text-align: center;
  padding: 2rem;
  background: white;
  border-radius: 15px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease;
}

.expertise-item:hover {
  transform: translateY(-5px);
}

.expertise-item i {
  font-size: 2.5rem;
  color: #2563eb;
  margin-bottom: 1rem;
}

.expertise-item h4 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #1a202c;
}

/* Research Section */
.research {
  padding: 6rem 0;
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.research-card {
  background: white;
  padding: 2.5rem;
  border-radius: 15px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  border-top: 4px solid #2563eb;
}

.research-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.research-icon {
  width: 60px;
  height: 60px;
  background: linear-gradient(45deg, #2563eb, #3b82f6);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.research-icon i {
  font-size: 1.5rem;
  color: white;
}

.research-card h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: #1a202c;
}

.research-card p {
  color: #4a5568;
  line-height: 1.6;
}

/* Publications Section */
.publications {
  padding: 6rem 0;
  background: #f8fafc;
}

.publications-list {
  max-width: 800px;
  margin: 0 auto;
}

.publication-item {
  display: flex;
  gap: 2rem;
  margin-bottom: 2.5rem;
  padding: 2rem;
  background: white;
  border-radius: 15px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease;
}

.publication-item:hover {
  transform: translateX(10px);
}

.publication-year {
  font-size: 1.2rem;
  font-weight: 700;
  color: #2563eb;
  min-width: 60px;
}

.publication-content h4 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #1a202c;
}

.publication-authors {
  font-style: italic;
  color: #4a5568;
  margin-bottom: 0.3rem;
}

.publication-journal {
  color: #718096;
  margin-bottom: 1rem;
}

.publication-link {
  color: #2563eb;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
}

.publication-link:hover {
  color: #1d4ed8;
}

/* Contact Section */
.contact {
  padding: 6rem 0;
  background: linear-gradient(135deg, #1a202c 0%, #2d3748 100%);
  color: white;
}

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

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  max-width: 800px;
  margin: 0 auto;
}

.contact-item {
  display: flex;
  gap: 1rem;
  margin-bottom: 2rem;
}

.contact-item i {
  font-size: 1.5rem;
  color: #3b82f6;
  margin-top: 0.2rem;
}

.contact-item h4 {
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.contact-item p {
  opacity: 0.9;
  line-height: 1.5;
}

.social-links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.social-link {
  color: white;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem;
  border-radius: 5px;
  transition: all 0.3s ease;
}

.social-link:hover {
  background: rgba(59, 130, 246, 0.1);
  color: #3b82f6;
}

/* Footer */
.footer {
  background: #1a202c;
  color: white;
  text-align: center;
  padding: 2rem 0;
}

/* Animations */
@keyframes float {
  0%, 100% { transform: translate(-50%, -50%) translateY(0px); }
  50% { transform: translate(-50%, -50%) translateY(-20px); }
}

@keyframes rotate {
  from { transform: translate(-50%, -50%) rotate(0deg); }
  to { transform: translate(-50%, -50%) rotate(360deg); }
}

@keyframes pulse {
  0%, 100% { opacity: 0.7; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.2); }
}

/* Responsive Design */
@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }
  
  .nav-menu {
    position: fixed;
    left: -100%;
    top: 70px;
    flex-direction: column;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    width: 100%;
    text-align: center;
    transition: 0.3s;
    padding: 2rem 0;
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .hero-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .globe-container {
    width: 300px;
    height: 300px;
  }
  
  .contact-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  .publication-item {
    flex-direction: column;
    gap: 1rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 1rem;
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .expertise-grid {
    grid-template-columns: 1fr;
  }
  
  .research-grid {
    grid-template-columns: 1fr;
  }
}