/* ===================================
   CSS Custom Properties & Reset
   =================================== */
:root {
  --primary-color: #6366f1;
  --secondary-color: #8b5cf6;
  --text-dark: #1f2937;
  --text-light: #6b7280;
  --bg-white: #ffffff;
  --bg-light: #f9fafb;
  --bg-dark: #111827;
  --border-color: #e5e7eb;
  --success-color: #10b981;
  --error-color: #ef4444;
  --gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: var(--bg-white);
  overflow-x: hidden;
}

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

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

ul {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
  transition: var(--transition);
}

/* ===================================
   Typography
   =================================== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-dark);
}

h1 {
  font-size: 3.5rem;
}

h2 {
  font-size: 2.5rem;
}

h3 {
  font-size: 2rem;
}

h4 {
  font-size: 1.5rem;
}

p {
  margin-bottom: 1rem;
  color: var(--text-light);
  font-size: 1.125rem;
}

/* ===================================
   Navigation
   =================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  transition: var(--transition);
}

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

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  /*display: flex;*/
  align-items: center;
  gap: 0.5rem;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-dark);
}

.logo img {
  height: 50px;
  width: auto;
  max-width: 200px;
}

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

.nav-links a {
  color: var(--text-light);
  font-weight: 500;
  font-size: 1rem;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient);
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary-color);
}

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

.nav-cta {
  padding: 0.75rem 1.5rem;
  background: var(--gradient);
  color: white !important;
  border-radius: 8px;
  font-weight: 600;
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  color: white !important;
}

.nav-cta::after {
  display: none !important;
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
}

.mobile-menu-btn span {
  width: 25px;
  height: 3px;
  background: var(--text-dark);
  border-radius: 3px;
  transition: var(--transition);
}

/* ===================================
   Layout & Containers
   =================================== */
.main-content {
  margin-top: 80px;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
}

.section {
  padding: 6rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

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

.section-subtitle {
  font-size: 1.25rem;
  color: var(--text-light);
  max-width: 700px;
  margin: 0 auto;
}

/* ===================================
   Hero Section
   =================================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, #f9fafb 0%, #e5e7eb 100%);
  position: relative;
  overflow: hidden;
  padding: 6rem 0;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 30% 50%, rgba(99, 102, 241, 0.1), transparent 50%),
              radial-gradient(circle at 70% 50%, rgba(139, 92, 246, 0.1), transparent 50%);
  animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  text-align: center;
  animation: fadeInUp 1s ease-out;
}

.hero-title {
  font-size: 4.5rem;
  line-height: 1.1;
  margin-bottom: 1.5rem;
}

.hero-gradient-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.5rem;
  color: var(--text-light);
  margin-bottom: 2.5rem;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

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

/* ===================================
   Buttons
   =================================== */
.btn {
  display: inline-block;
  padding: 1rem 2rem;
  font-size: 1.125rem;
  font-weight: 600;
  border-radius: 10px;
  transition: var(--transition);
  text-align: center;
}

.btn-primary {
  background: var(--gradient);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-xl);
}

.btn-secondary {
  background: white;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

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

/* ===================================
   Cards
   =================================== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.card {
  background: white;
  border-radius: 16px;
  padding: 2.5rem;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  border: 1px solid var(--border-color);
}

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

.card-icon {
  width: 60px;
  height: 60px;
  background: var(--gradient);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 2rem;
}

.card-title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-dark);
}

.card-description {
  color: var(--text-light);
  line-height: 1.7;
}

.card-features {
  margin-top: 1.5rem;
}

.card-features li {
  padding: 0.5rem 0;
  color: var(--text-light);
  position: relative;
  padding-left: 1.5rem;
}

.card-features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--primary-color);
  font-weight: bold;
}

/* ===================================
   Features Section
   =================================== */
.features {
  background: var(--bg-light);
}

.feature-card {
  display: flex;
  gap: 2rem;
  padding: 3rem;
  background: white;
  border-radius: 16px;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.feature-card:hover {
  box-shadow: var(--shadow-lg);
}

.feature-icon {
  flex-shrink: 0;
  width: 80px;
  height: 80px;
  background: var(--gradient);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
}

.feature-content h3 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
}

/* ===================================
   Products Page
   =================================== */
.product-detail {
  padding: 4rem 0;
  border-bottom: 1px solid var(--border-color);
}

.product-detail:last-child {
  border-bottom: none;
}

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

.product-header h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.product-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.product-info h3 {
  font-size: 1.75rem;
  margin-top: 2rem;
  margin-bottom: 1rem;
}

.product-benefits {
  background: var(--bg-light);
  padding: 2.5rem;
  border-radius: 16px;
}

.product-benefits ul {
  display: grid;
  gap: 1rem;
}

.product-benefits li {
  display: flex;
  gap: 1rem;
  align-items: start;
}

.product-benefits li::before {
  content: '→';
  color: var(--primary-color);
  font-size: 1.5rem;
  font-weight: bold;
  flex-shrink: 0;
}

/* ===================================
   Contact Form
   =================================== */
.contact-section {
  background: var(--bg-light);
}

.contact-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
}

.contact-info h3 {
  font-size: 2rem;
  margin-bottom: 2rem;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 2rem;
}

.contact-item {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.contact-item-icon {
  width: 50px;
  height: 50px;
  background: var(--gradient);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.5rem;
  flex-shrink: 0;
}

.form-container {
  background: white;
  padding: 3rem;
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
}

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

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-dark);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 1rem;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
  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(99, 102, 241, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 150px;
}

.form-message {
  padding: 1rem;
  border-radius: 8px;
  margin-bottom: 1rem;
  display: none;
}

.form-message.success {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success-color);
  border: 1px solid var(--success-color);
}

.form-message.error {
  background: rgba(239, 68, 68, 0.1);
  color: var(--error-color);
  border: 1px solid var(--error-color);
}

/* ===================================
   Research Blog
   =================================== */
.research-filters {
  display: flex;
  gap: 1rem;
  margin-bottom: 3rem;
  flex-wrap: wrap;
  justify-content: center;
}

.filter-btn {
  padding: 0.75rem 1.5rem;
  background: white;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  font-weight: 600;
  color: var(--text-dark);
}

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

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

.research-card {
  background: white;
  border-radius: 16px;
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  border: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

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

.research-meta {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.research-date,
.research-category {
  font-size: 0.875rem;
  color: var(--text-light);
  font-weight: 500;
}

.research-category {
  background: var(--bg-light);
  padding: 0.25rem 0.75rem;
  border-radius: 6px;
}

.research-title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-dark);
}

.research-authors {
  font-size: 0.95rem;
  color: var(--primary-color);
  margin-bottom: 1rem;
  font-weight: 500;
}

.research-abstract {
  color: var(--text-light);
  line-height: 1.6;
  flex-grow: 1;
}

.research-link {
  margin-top: 1.5rem;
  color: var(--primary-color);
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.research-link:hover {
  gap: 1rem;
}

/* ===================================
   About Page
   =================================== */
.about-hero {
  text-align: center;
  padding: 6rem 0;
  background: var(--bg-light);
}

.mission-vision {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  margin: 4rem 0;
}

.mission-card,
.vision-card {
  background: white;
  padding: 3rem;
  border-radius: 16px;
  box-shadow: var(--shadow-md);
}

.mission-card h3,
.vision-card h3 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

.value-item {
  text-align: center;
  padding: 2rem;
}

.value-icon {
  width: 70px;
  height: 70px;
  background: var(--gradient);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  font-size: 2rem;
}

/* ===================================
   Footer
   =================================== */
.footer {
  background: var(--bg-dark);
  color: white;
  padding: 4rem 0 2rem;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-about h3 {
  color: white;
  margin-bottom: 1rem;
}

.footer-about p {
  color: rgba(255, 255, 255, 0.7);
}

.footer-links h4 {
  color: white;
  margin-bottom: 1rem;
  font-size: 1.125rem;
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  transition: var(--transition);
}

.footer-links a:hover {
  color: white;
  padding-left: 5px;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  color: rgba(255, 255, 255, 0.7);
}

/* ===================================
   Animations
   =================================== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.scale-in {
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.5s ease-out, transform 0.5s ease-out;
}

.scale-in.visible {
  opacity: 1;
  transform: scale(1);
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 3.5rem;
  }
  
  .product-content {
    grid-template-columns: 1fr;
  }
  
  .mission-vision {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }
  
  h2 {
    font-size: 2rem;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .nav-links {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background: white;
    flex-direction: column;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
  }
  
  .nav-links.active {
    left: 0;
  }
  
  .mobile-menu-btn {
    display: flex;
  }
  
  .mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
  }
  
  .mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
  }
  
  .mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
  }
  
  .hero {
    min-height: 80vh;
    padding: 4rem 0;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.25rem;
  }
  
  .hero-cta {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
  }
  
  .contact-container {
    grid-template-columns: 1fr;
  }
  
  .feature-card {
    flex-direction: column;
  }
  
  .research-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .container {
    padding: 0 1.5rem;
  }
  
  .section {
    padding: 4rem 0;
  }
}

@media (max-width: 480px) {
  html {
    font-size: 14px;
  }
  
  .nav-container {
    padding: 1rem 1.5rem;
  }
  
  .form-container {
    padding: 2rem 1.5rem;
  }
  
  .card {
    padding: 1.5rem;
  }
}