/* Base Styles */
:root {
  --primary-color: #6c63ff;
  --primary-dark: #564fd8;
  --secondary-color: #ff6584;
  --dark-color: #2d3748;
  --dark-gray: #4a5568;
  --medium-gray: #718096;
  --light-gray: #edf2f7;
  --lighter-gray: #f7fafc;
  --white: #ffffff;
  --black: #000000;
  --success-color: #48bb78;
  --warning-color: #ed8936;
  --error-color: #f56565;
  --font-primary: 'Inter', sans-serif;
  --font-mono: 'Source Code Pro', monospace;
  --transition: all 0.3s ease;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;
}

/* Dark Theme Variables */
[data-theme="dark"] {
  --dark-color: #f7fafc;
  --dark-gray: #e2e8f0;
  --medium-gray: #cbd5e0;
  --light-gray: #2d3748;
  --lighter-gray: #1a202c;
  --white: #1a202c;
  --black: #ffffff;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  line-height: 1.6;
  color: var(--dark-color);
  background-color: var(--lighter-gray);
  transition: var(--transition);
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}

p {
  margin-bottom: 1rem;
}

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

ul {
  list-style: none;
}

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

.highlight {
  color: var(--primary-color);
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 6rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

.section-title {
  font-size: 2.5rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background-color: var(--primary-color);
  border-radius: var(--radius-full);
}

.section-divider {
  width: 60px;
  height: 2px;
  background-color: var(--primary-color);
  margin: 1rem auto;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--medium-gray);
  max-width: 700px;
  margin: 0 auto;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
  border: 2px solid transparent;
}

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

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

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

.btn.secondary:hover {
  background-color: var(--primary-color);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn.ghost {
  background-color: transparent;
  color: var(--dark-color);
  border-color: var(--dark-color);
}

.btn.ghost:hover {
  background-color: var(--dark-color);
  color: var(--white);
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 1.5rem 0;
  background-color: rgba(255, 255, 255, 0.95);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  transition: var(--transition);
}

[data-theme="dark"] .navbar {
  background-color: rgba(26, 32, 44, 0.95);
}

.navbar.scrolled {
  padding: 1rem 0;
  box-shadow: var(--shadow-md);
}

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

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--dark-color);
}

.logo .highlight {
  color: var(--primary-color);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  font-weight: 600;
  position: relative;
  padding: 0.5rem 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary-color);
  transition: var(--transition);
}

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

.theme-toggle {
  cursor: pointer;
  font-size: 1.2rem;
  color: var(--dark-color);
  transition: var(--transition);
}

.theme-toggle:hover {
  color: var(--primary-color);
  transform: rotate(30deg);
}

.hamburger {
  display: none;
  cursor: pointer;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 18px;
}

.hamburger .bar {
  width: 100%;
  height: 2px;
  background-color: var(--dark-color);
  transition: var(--transition);
}

.hamburger.active .bar:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.hamburger.active .bar:nth-child(2) {
  opacity: 0;
}

.hamburger.active .bar:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 80px;
  background: linear-gradient(135deg, var(--lighter-gray) 0%, var(--light-gray) 100%);
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.hero-content {
  max-width: 600px;
}

.subtitle {
  font-size: 1.2rem;
  color: var(--medium-gray);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 2px;
}

.title {
  font-size: 3.5rem;
  line-height: 1.1;
  margin-bottom: 1.5rem;
}

.hero-text {
  font-size: 1.1rem;
  color: var(--dark-gray);
  margin-bottom: 2rem;
}

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

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

.social-links a {
  font-size: 1.2rem;
  color: var(--dark-gray);
  transition: var(--transition);
}

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

.hero-image {
  position: relative;
}

.image-container {
  position: relative;
  width: 380px;
  height: 380px;
  margin: 0 auto;
}

.profile-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  border: 8px solid var(--white);
}

.tech-icons {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
}

.icon {
  position: absolute;
  width: 60px;
  height: 60px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--white);
  box-shadow: var(--shadow-lg);
  animation: float 6s ease-in-out infinite;
}

.icon.python {
  background-color: #3776ab;
  top: -20px;
  left: -20px;
  animation-delay: 0s;
}

.icon.tensorflow {
  background-color: #ff6f00;
  top: -20px;
  right: -20px;
  animation-delay: 1s;
}

.icon.sql {
  background-color: #00758f;
  bottom: -20px;
  left: -20px;
  animation-delay: 2s;
}

.icon.cloud {
  background-color: #ff9900;
  bottom: -20px;
  right: -20px;
  animation-delay: 3s;
}

.scroll-indicator {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  animation: bounce 2s infinite;
}

.scroll-indicator a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  background-color: var(--primary-color);
  color: var(--white);
  font-size: 1.2rem;
}

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

.about-text p {
  margin-bottom: 1.5rem;
  color: var(--dark-gray);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
}

.stat-item {
  text-align: center;
  padding: 1.5rem;
  background-color: var(--white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.stat-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--medium-gray);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.experience-timeline {
  position: relative;
  padding-left: 2rem;
}

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

.timeline-item {
  position: relative;
  padding-bottom: 2rem;
}

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

.timeline-item::before {
  content: '';
  position: absolute;
  top: 5px;
  left: -2.3rem;
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
  background-color: var(--primary-color);
  border: 2px solid var(--white);
}

.timeline-year {
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

.timeline-content h4 {
  font-size: 1.2rem;
  margin-bottom: 0.3rem;
}

.timeline-content p {
  color: var(--medium-gray);
  font-size: 0.9rem;
}

/* Expertise Section */
.expertise {
  background-color: var(--white);
}

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

.expertise-card {
  background-color: var(--lighter-gray);
  padding: 2rem;
  border-radius: var(--radius-md);
  transition: var(--transition);
  border-bottom: 4px solid transparent;
}

.expertise-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-bottom-color: var(--primary-color);
}

.expertise-icon {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: 1.5rem;
}

.expertise-card h3 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
}

.expertise-card ul {
  margin-left: 1rem;
}

.expertise-card li {
  margin-bottom: 0.5rem;
  color: var(--dark-gray);
  position: relative;
  padding-left: 1.2rem;
}

.expertise-card li::before {
  content: '▹';
  position: absolute;
  left: 0;
  color: var(--primary-color);
}

.skills-chart {
  background-color: var(--lighter-gray);
  padding: 2rem;
  border-radius: var(--radius-md);
  margin-top: 3rem;
}

.skills-title {
  text-align: center;
  margin-bottom: 2rem;
}

.chart-container {
  max-width: 800px;
  margin: 0 auto;
}

.skill-item {
  margin-bottom: 1.5rem;
}

.skill-name {
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.skill-bar {
  width: 100%;
  height: 10px;
  background-color: var(--light-gray);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.skill-level {
  height: 100%;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: var(--radius-full);
  position: relative;
  width: 0;
}

.skill-level::after {
  content: attr(data-level);
  position: absolute;
  right: 10px;
  top: -25px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--primary-color);
}

/* Projects Section */
.projects {
  background-color: var(--lighter-gray);
}

.projects-filter {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.5rem 1.5rem;
  border-radius: var(--radius-full);
  background-color: transparent;
  border: 1px solid var(--medium-gray);
  color: var(--medium-gray);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

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

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 2rem;
}

.project-card {
  background-color: var(--white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.project-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

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

.project-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.project-card:hover .project-image img {
  transform: scale(1.05);
}

.project-links {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  background-color: rgba(108, 99, 255, 0.8);
  opacity: 0;
  transition: var(--transition);
}

.project-card:hover .project-links {
  opacity: 1;
}

.project-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  border-radius: var(--radius-full);
  background-color: var(--white);
  color: var(--primary-color);
  font-size: 1.2rem;
  transition: var(--transition);
}

.project-links a:hover {
  background-color: var(--dark-color);
  color: var(--white);
}

.project-content {
  padding: 1.5rem;
}

.project-content h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.project-content p {
  color: var(--dark-gray);
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

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

.project-tech span {
  font-size: 0.8rem;
  padding: 0.3rem 0.8rem;
  background-color: var(--light-gray);
  border-radius: var(--radius-full);
  color: var(--dark-gray);
}

.projects-cta {
  text-align: center;
  margin-top: 3rem;
}

/* Publications Section */
.publications-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 2rem;
}

.publication-card {
  background-color: var(--white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

.publication-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.publication-image {
  height: 200px;
  overflow: hidden;
}

.publication-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.publication-card:hover .publication-image img {
  transform: scale(1.05);
}

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

.publication-meta {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
  color: var(--medium-gray);
}

.publication-type {
  background-color: var(--light-gray);
  padding: 0.2rem 0.8rem;
  border-radius: var(--radius-full);
}

.publication-content h3 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
}

.publication-abstract {
  color: var(--dark-gray);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.publication-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--primary-color);
  font-weight: 600;
  transition: var(--transition);
}

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

.publications-cta {
  text-align: center;
  margin-top: 3rem;
}

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

.contact-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.info-item {
  display: flex;
  gap: 1rem;
}

.info-icon {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-full);
  background-color: var(--primary-color);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.info-content h4 {
  font-size: 1.1rem;
  margin-bottom: 0.3rem;
}

.info-content a {
  color: var(--primary-color);
  font-weight: 500;
}

.info-content a:hover {
  text-decoration: underline;
}

.contact-social {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
}

.contact-social a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  background-color: var(--light-gray);
  color: var(--dark-color);
  font-size: 1rem;
  transition: var(--transition);
}

.contact-social a:hover {
  background-color: var(--primary-color);
  color: var(--white);
  transform: translateY(-3px);
}

.contact-form {
  background-color: var(--lighter-gray);
  padding: 2rem;
  border-radius: var(--radius-md);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.8rem 1rem;
  border: 1px solid var(--light-gray);
  border-radius: var(--radius-sm);
  font-family: var(--font-primary);
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(108, 99, 255, 0.2);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

/* Footer */
.footer {
  background-color: var(--dark-color);
  color: var(--white);
  padding: 4rem 0 0;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-logo {
  margin-bottom: 1.5rem;
}

.footer-logo a {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--white);
}

.footer-logo .highlight {
  color: var(--primary-color);
}

.footer-logo p {
  color: var(--medium-gray);
}

.footer-links h4 {
  font-size: 1.2rem;
  margin-bottom: 1.5rem;
  position: relative;
  padding-bottom: 0.5rem;
}

.footer-links h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background-color: var(--primary-color);
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.footer-links a {
  color: var(--medium-gray);
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary-color);
  padding-left: 5px;
}

.newsletter-form {
  display: flex;
  margin-top: 1rem;
}

.newsletter-form input {
  flex-grow: 1;
  padding: 0.8rem 1rem;
  border: none;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  font-family: var(--font-primary);
}

.newsletter-form button {
  padding: 0 1.2rem;
  background-color: var(--primary-color);
  color: var(--white);
  border: none;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  cursor: pointer;
  transition: var(--transition);
}

.newsletter-form button:hover {
  background-color: var(--primary-dark);
}

.footer-bottom {
  padding: 1.5rem 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.footer-legal a {
  color: var(--medium-gray);
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-legal a:hover {
  color: var(--primary-color);
}

.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  border-radius: var(--radius-full);
  background-color: var(--primary-color);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
  z-index: 999;
}

.back-to-top.active {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background-color: var(--primary-dark);
  transform: translateY(-3px);
}

/* Animations */
@keyframes float {
  0% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-10px);
  }
  100% {
    transform: translateY(0px);
  }
}

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

/* Responsive Styles */
@media (max-width: 992px) {
  .hero .container {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  .hero-content {
    order: 2;
    text-align: center;
    max-width: 100%;
  }
  
  .hero-buttons {
    justify-content: center;
  }
  
  .social-links {
    justify-content: center;
  }
  
  .hero-image {
    order: 1;
  }
  
  .about-content {
    grid-template-columns: 1fr;
  }
  
  .contact-content {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background-color: var(--white);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    transition: var(--transition);
    z-index: 999;
  }
  
  [data-theme="dark"] .nav-links {
    background-color: var(--lighter-gray);
  }
  
  .nav-links.active {
    left: 0;
  }
  
  .hamburger {
    display: flex;
  }
  
  .section {
    padding: 4rem 0;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .title {
    font-size: 2.5rem;
  }
  
  .projects-grid,
  .publications-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 576px) {
  .hero-buttons {
    flex-direction: column;
  }
  
  .about-stats {
    grid-template-columns: 1fr;
  }
  
  .stat-item {
    padding: 1rem;
  }
  
  .stat-number {
    font-size: 2rem;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
  
  .footer-legal {
    justify-content: center;
  }
}