/* ========================================
   Variables & Root Styles
======================================== */
:root {
  /* Color Palette - Blue & Green */
  --primary-blue: #0066cc;
  --primary-blue-dark: #004999;
  --primary-blue-light: #3385d6;

  --primary-green: #00b894;
  --primary-green-dark: #00916d;
  --primary-green-light: #33c9a8;

  --secondary-cyan: #00cec9;
  --secondary-teal: #00b8a9;

  /* Gradient Colors */
  --gradient-primary: linear-gradient(135deg, var(--primary-blue) 0%, var(--primary-green) 100%);
  --gradient-secondary: linear-gradient(135deg, var(--secondary-cyan) 0%, var(--primary-blue) 100%);
  --gradient-overlay: linear-gradient(135deg, rgba(0, 102, 204, 0.95) 0%, rgba(0, 184, 148, 0.95) 100%);

  /* Neutral Colors */
  --dark: #1a1a2e;
  --dark-light: #2d2d44;
  --gray: #6c757d;
  --gray-light: #e9ecef;
  --white: #ffffff;

  /* Spacing */
  --section-padding: 100px;
  --container-padding: 15px;

  /* Typography */
  --font-family: 'IranSans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Transitions */
  --transition-speed: 0.3s;

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
  --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.2);
}

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

body {
  font-family: var(--font-family);
  line-height: 1.8;
  color: var(--dark);
  background-color: var(--white);
  overflow-x: hidden;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 1rem;
}

p {
  margin-bottom: 1rem;
}

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

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

/* ========================================
   Utility Classes
======================================== */
.section-padding {
  padding: var(--section-padding) 0;
}

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

.bg-gradient {
  background: linear-gradient(135deg, #f5f7fa 0%, #e9f2f9 100%);
}

/* ========================================
   Navbar
======================================== */
.navbar {
  padding: 1rem 0;
  transition: all 0.3s ease;

}

.navbar.scrolled {
  background: rgba(26, 26, 46, 0.98);
  backdrop-filter: blur(15px);
  box-shadow: var(--shadow-md);
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: bold;
  font-size: 1.5rem;
  z-index: 1001;
}

.navbar-brand .logo {
  height: 40px;
  width: auto;
}

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

/* Desktop Navigation */
.desktop-nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  color: var(--white) !important;
  font-weight: 500;
  padding: 0.5rem 1rem !important;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  right: 50%;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: all var(--transition-speed) ease;
}

.nav-link:hover::after {
  width: 80%;
  right: 10%;
}

.navbar-actions {
  display: flex;
  gap: 10px;
  margin-right: 20px;
}

.btn-login {
  padding: 0.5rem 1.5rem;
  border: 2px solid var(--primary-green);
  color: var(--primary-green);
  border-radius: 50px;
  font-weight: 600;
  transition: all var(--transition-speed) ease;
}

.btn-login:hover {
  background: var(--primary-green);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0, 184, 148, 0.3);
}

.btn-register {
  padding: 0.5rem 1.5rem;
  background: var(--gradient-primary);
  color: var(--white);
  border-radius: 50px;
  font-weight: 600;
  border: none;
  transition: all var(--transition-speed) ease;
}

.btn-register:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0, 102, 204, 0.3);
}

/* ========================================
   Mobile Menu Styles
======================================== */

/* Mobile Menu Toggle Button */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: transparent;
  border: none;
  padding: 8px;
  cursor: pointer;
  z-index: 1001;
  transition: all 0.3s ease;
}

.hamburger-line {
  width: 28px;
  height: 3px;
  background: linear-gradient(135deg, var(--primary-blue) 0%, var(--primary-green) 100%);
  border-radius: 3px;
  transition: all 0.3s ease;
  box-shadow: 0 2px 5px rgba(0, 102, 204, 0.3);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
  transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
  opacity: 0;
  transform: translateX(20px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
  transform: rotate(-45deg) translate(8px, -8px);
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
  position: fixed;
  top: 0;
  right: -100%;
  width: 100%;
  height: 100vh;
  background: linear-gradient(135deg, rgba(15, 32, 39, 0.98) 0%, rgba(32, 58, 67, 0.98) 50%, rgba(44, 83, 100, 0.98) 100%);
  backdrop-filter: blur(20px);
  z-index: 1000;
  transition: right 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
  overflow-y: auto;
}

.mobile-menu-overlay.active {
  right: 0;
}

.mobile-menu-content {
  padding: 100px 30px 30px;
  max-width: 500px;
  margin: 0 auto;
}

/* Mobile Menu Header */
.mobile-menu-header {
  text-align: center;
  margin-bottom: 3rem;
  animation: fadeInDown 0.6s ease;
}

.mobile-logo {
  height: 60px;
  width: auto;
  margin-bottom: 1rem;
  filter: drop-shadow(0 5px 15px rgba(0, 184, 148, 0.3));
}

.mobile-brand {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-size: 2rem;
  font-weight: 800;
  margin: 0;
}

/* Mobile Navigation List */
.mobile-nav-list {
  list-style: none;
  padding: 0;
  margin: 0 0 2rem 0;
}

.mobile-nav-item {
  margin-bottom: 0.5rem;
  opacity: 0;
  transform: translateX(50px);
  animation: slideInRight 0.5s ease forwards;
}

.mobile-nav-item:nth-child(1) { animation-delay: 0.1s; }
.mobile-nav-item:nth-child(2) { animation-delay: 0.15s; }
.mobile-nav-item:nth-child(3) { animation-delay: 0.2s; }
.mobile-nav-item:nth-child(4) { animation-delay: 0.25s; }
.mobile-nav-item:nth-child(5) { animation-delay: 0.3s; }
.mobile-nav-item:nth-child(6) { animation-delay: 0.35s; }

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.5rem;
  background: rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 15px;
  color: var(--white);
  font-size: 1.1rem;
  font-weight: 600;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.mobile-nav-link::before {
  content: '';
  position: absolute;
  top: 0;
  right: -100%;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  transition: right 0.3s ease;
  z-index: -1;
}

.mobile-nav-link:hover::before {
  right: 0;
}

.mobile-nav-link:hover {
  transform: translateX(-5px);
  border-color: var(--primary-blue);
  box-shadow: 0 5px 20px rgba(0, 102, 204, 0.3);
}

.mobile-nav-link i {
  font-size: 1.3rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  min-width: 25px;
}

.mobile-nav-link:hover i {
  -webkit-text-fill-color: var(--white);
}

/* Mobile Menu Actions */
.mobile-menu-actions {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2rem;
  opacity: 0;
  transform: translateY(30px);
  animation: fadeInUp 0.6s ease 0.4s forwards;
}

.mobile-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-radius: 15px;
  font-size: 1rem;
  font-weight: 600;
  transition: all 0.3s ease;
  text-align: center;
}

.mobile-btn i {
  font-size: 1.2rem;
}

.mobile-btn-login {
  background: rgba(0, 184, 148, 0.1);
  border: 2px solid var(--primary-green);
  color: var(--primary-green);
}

.mobile-btn-login:hover {
  background: var(--primary-green);
  color: var(--white);
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 184, 148, 0.4);
}

.mobile-btn-register {
  background: var(--gradient-primary);
  border: 2px solid transparent;
  color: var(--white);
}

.mobile-btn-register:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 102, 204, 0.4);
}

/* Mobile Menu Footer */
.mobile-menu-footer {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  opacity: 0;
  animation: fadeIn 0.6s ease 0.5s forwards;
}

.mobile-menu-footer p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.9rem;
  margin: 0;
}

/* Animations */
@keyframes slideInRight {
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

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

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

@keyframes fadeIn {
  to {
    opacity: 1;
  }
}

/* Responsive Breakpoints */
@media (max-width: 991px) {
  .mobile-menu-toggle {
    display: flex;
  }

  .desktop-nav {
    display: none;
  }
}

@media (min-width: 992px) {
  .mobile-menu-overlay {
    display: none;
  }
}


/* ========================================
   Hero Section
======================================== */
.hero-section {
  position: relative;
  min-height: 100vh;
  background: linear-gradient(135deg, #0f2027 0%, #203a43 50%, #2c5364 100%);
  overflow: hidden;
  padding-top: 80px;
}

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

.hero-section .container {
  position: relative;
  z-index: 2;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--white);
  margin-bottom: 1.5rem;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 2rem;
  max-width: 600px;
}

.hero-stats {
  display: flex;
  gap: 3rem;
  margin: 3rem 0;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

.stat-label {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.95rem;
}

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

.btn-primary {
  background: var(--gradient-primary);
  border: none;
  padding: 0.875rem 2rem;
  border-radius: 50px;
  font-weight: 600;
  color: var(--white);
  transition: all var(--transition-speed) ease;
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(0, 102, 204, 0.4);
}

.btn-outline-light {
  border: 2px solid var(--white);
  color: var(--white);
  padding: 0.875rem 2rem;
  border-radius: 50px;
  font-weight: 600;
  background: transparent;
  transition: all var(--transition-speed) ease;
}

.btn-outline-light:hover {
  background: var(--white);
  color: var(--primary-blue);
  transform: translateY(-3px);
}

/* Hero Illustration */
.hero-illustration {
  position: relative;
  height: 600px;
}

.dna-helix {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 300px;
  height: 400px;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><path d="M50 0 Q 75 25 50 50 Q 25 75 50 100" fill="none" stroke="%2300b894" stroke-width="2" opacity="0.3"/></svg>');
  background-size: contain;
  animation: rotate 20s linear infinite;
}

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

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

.floating-cards {
  position: relative;
  width: 100%;
  height: 100%;
}

.float-card {
  position: absolute;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 20px;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  transition: all var(--transition-speed) ease;
}

.float-card:hover {
  transform: translateY(-10px);
  background: rgba(255, 255, 255, 0.15);
}

.float-card i {
  font-size: 2rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.float-card span {
  color: var(--white);
  font-size: 0.9rem;
  font-weight: 600;
}

.card-1 {
  top: 10%;
  right: 10%;
  animation: float 3s ease-in-out infinite;
}

.card-2 {
  top: 40%;
  left: 0;
  animation: float 3s ease-in-out 0.5s infinite;
}

.card-3 {
  bottom: 30%;
  right: 5%;
  animation: float 3s ease-in-out 1s infinite;
}

.card-4 {
  bottom: 10%;
  left: 15%;
  animation: float 3s ease-in-out 1.5s infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-20px);
  }
}

/* Scroll Indicator */
.scroll-indicator {
  position: absolute;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 3;
}

.mouse {
  width: 30px;
  height: 50px;
  border: 2px solid rgba(255, 255, 255, 0.5);
  border-radius: 15px;
  display: flex;
  justify-content: center;
  padding-top: 10px;
}

.wheel {
  width: 4px;
  height: 10px;
  background: var(--white);
  border-radius: 2px;
  animation: scroll 2s ease-in-out infinite;
}

@keyframes scroll {

  0%,
  100% {
    opacity: 0;
    transform: translateY(0);
  }

  50% {
    opacity: 1;
    transform: translateY(10px);
  }
}

/* ========================================
   Section Headers
======================================== */
.section-header {
  margin-bottom: 3rem;
}

.section-badge {
  display: inline-block;
  padding: 0.5rem 1.5rem;
  background: linear-gradient(135deg, rgba(0, 102, 204, 0.1) 0%, rgba(0, 184, 148, 0.1) 100%);
  border: 2px solid var(--primary-blue);
  border-radius: 50px;
  color: var(--primary-blue);
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
}

.section-description {
  font-size: 1.1rem;
  color: var(--gray);
  max-width: 800px;
  margin: 0 auto;
}

/* ========================================
   About Section
======================================== */
.feature-list {
  list-style: none;
  padding: 0;
  margin: 2rem 0;
}

.feature-list li {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--gray-light);
}

.feature-list li:last-child {
  border-bottom: none;
}

.feature-list i {
  color: var(--primary-green);
  font-size: 1.5rem;
}

.about-visual img {
  filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.1));
  animation: float 6s ease-in-out infinite;
}

/* ========================================
   Features Section
======================================== */
.feature-card {
  background: var(--white);
  border-radius: 20px;
  padding: 2.5rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
  height: 100%;
  border: 2px solid transparent;
}

.feature-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-blue);
}

.feature-icon {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  box-shadow: 0 10px 30px rgba(0, 102, 204, 0.3);
}

.feature-icon i {
  font-size: 2rem;
  color: var(--white);
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

.feature-card p {
  color: var(--gray);
  margin-bottom: 0;
}

/* ========================================
   Courses Section
======================================== */
.course-tabs {
  border-bottom: none;
  gap: 1rem;
  margin-bottom: 3rem !important;
}

.course-tabs .nav-link {
  background: var(--white);
  border: 2px solid var(--gray-light);
  border-radius: 50px;
  padding: 0.75rem 2rem;
  color: var(--dark);
  font-weight: 600;
  transition: all var(--transition-speed) ease;
}

.course-tabs .nav-link.active {
  background: var(--gradient-primary);
  border-color: transparent;
  color: var(--white);
  box-shadow: 0 5px 15px rgba(0, 102, 204, 0.3);
}

.course-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
  height: 100%;
}

.course-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

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

.course-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: all 0.5s ease;
}

.course-card:hover .course-image img {
  transform: scale(1.1);
}

.course-badge {
  position: absolute;
  top: 15px;
  right: 15px;
  background: var(--primary-green);
  color: var(--white);
  padding: 0.5rem 1rem;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
}

.course-badge.badge-new {
  background: var(--primary-blue);
}

.course-content {
  padding: 1.5rem;
}

.course-meta {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1rem;
  color: var(--gray);
  font-size: 0.9rem;
}

.course-meta span {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.course-content h3 {
  font-size: 1.15rem;
  margin-bottom: 1rem;
  color: var(--dark);
}

.course-content p {
  color: var(--gray);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.course-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1rem;
  border-top: 1px solid var(--gray-light);
}

.course-instructor {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.course-instructor img {
  width: 35px;
  height: 35px;
  border-radius: 50%;
  object-fit: cover;
}

.course-instructor span {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--dark);
}

/* ========================================
   Research Areas Section
======================================== */
.research-areas {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.research-category {
  background: var(--white);
  border-radius: 20px;
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
}

.research-category:hover {
  box-shadow: var(--shadow-lg);
  transform: translateX(-5px);
}

.category-header {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.category-icon {
  width: 60px;
  height: 60px;
  background: var(--gradient-primary);
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.category-icon i {
  font-size: 1.75rem;
  color: var(--white);
}

.category-header h3 {
  margin: 0;
  font-size: 1.5rem;
}

.research-item {
  background: linear-gradient(135deg, rgba(0, 102, 204, 0.05) 0%, rgba(0, 184, 148, 0.05) 100%);
  padding: 1.25rem;
  border-radius: 15px;
  display: flex;
  align-items: center;
  gap: 1rem;
  transition: all var(--transition-speed) ease;
  border: 2px solid transparent;
}

.research-item:hover {
  background: linear-gradient(135deg, rgba(0, 102, 204, 0.1) 0%, rgba(0, 184, 148, 0.1) 100%);
  border-color: var(--primary-blue);
  transform: translateX(5px);
}

.research-item i {
  font-size: 1.5rem;
  color: var(--primary-blue);
}

.research-item span {
  font-weight: 500;
}

/* ========================================
   Professors Section
======================================== */
.professor-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
  height: 100%;
}

.professor-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.professor-image {
  position: relative;
  height: 300px;
  overflow: hidden;
}

.professor-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: all 0.5s ease;
}

.professor-card:hover .professor-image img {
  transform: scale(1.1);
}

.professor-social {
  position: absolute;
  bottom: -50px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.5rem;
  transition: all var(--transition-speed) ease;
}

.professor-card:hover .professor-social {
  bottom: 20px;
}

.professor-social a {
  width: 40px;
  height: 40px;
  background: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
}

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

.professor-info {
  padding: 1.5rem;
  text-align: center;
}

.professor-info h4 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.professor-title {
  color: var(--gray);
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

.professor-stats {
  display: flex;
  justify-content: center;
  gap: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--gray-light);
}

.professor-stats span {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--gray);
}

.professor-stats i {
  color: var(--primary-blue);
}

/* ========================================
   Community Section
======================================== */
.community-features {
  margin: 2rem 0;
}

.community-feature-item {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: var(--white);
  border-radius: 15px;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-speed) ease;
}

.community-feature-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateX(5px);
}

.feature-icon-small {
  width: 60px;
  height: 60px;
  background: var(--gradient-primary);
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.feature-icon-small i {
  font-size: 1.5rem;
  color: var(--white);
}

.community-feature-item h5 {
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.community-feature-item p {
  margin: 0;
  color: var(--gray);
  font-size: 0.95rem;
}

.community-visual img {
  filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.1));
  animation: float 6s ease-in-out infinite;
}

/* ========================================
   CTA Section
======================================== */
.cta-section {
  padding: 80px 0;
  background: var(--gradient-primary);
}

.cta-card {
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 30px;
  padding: 3rem;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
}

.cta-card h2 {
  color: var(--white);
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.cta-card p {
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.1rem;
  margin-bottom: 0;
}

.cta-card .btn-light {
  background: var(--white);
  color: var(--primary-blue);
  padding: 1rem 2.5rem;
  border-radius: 50px;
  font-weight: 600;
  border: none;
  transition: all var(--transition-speed) ease;
}

.cta-card .btn-light:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(255, 255, 255, 0.3);
}

/* ========================================
   Contact Section
======================================== */
.contact-info-card {
  background: var(--white);
  border-radius: 20px;
  padding: 2.5rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-speed) ease;
  height: 100%;
}

.contact-info-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.contact-icon {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
}

.contact-icon i {
  font-size: 2rem;
  color: var(--white);
}

.contact-info-card h4 {
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

.contact-info-card p {
  color: var(--gray);
  margin-bottom: 0.5rem;
}

/* ========================================
   Footer
======================================== */
.footer {
  background: var(--dark);
  color: rgba(255, 255, 255, 0.8);
  padding: 4rem 0 2rem;
}

.footer-brand {
  margin-bottom: 2rem;
}

.footer-logo {
  height: 50px;
  margin-bottom: 1rem;
}

.footer-brand h3 {
  color: var(--white);
  margin-bottom: 1rem;
}

.footer-brand p {
  font-size: 0.95rem;
}

.footer-social {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
}

.footer-social a {
  width: 45px;
  height: 45px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-speed) ease;
}

.footer-social a:hover {
  background: var(--gradient-primary);
  transform: translateY(-3px);
}

.footer h5 {
  color: var(--white);
  margin-bottom: 1.5rem;
  font-size: 1.1rem;
}

.footer-links {
  list-style: none;
  padding: 0;
}

.footer-links li {
  margin-bottom: 0.75rem;
}

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

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

.footer-bottom {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
}

/* ========================================
   Responsive Design
======================================== */
@media (max-width: 991px) {
  .hero-title {
    font-size: 2.5rem;
  }

  .section-title {
    font-size: 2rem;
  }

  .hero-stats {
    gap: 2rem;
  }

  .stat-number {
    font-size: 2rem;
  }

  .hero-illustration {
    height: 400px;
    margin-top: 3rem;
  }

  .navbar-actions {
    margin-right: 0;
    margin-top: 1rem;
    width: 100%;
  }

  .btn-login,
  .btn-register {
    flex: 1;
    text-align: center;
  }
}

@media (max-width: 767px) {
  :root {
    --section-padding: 60px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 1.5rem;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .hero-buttons .btn {
    width: 100%;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .cta-card h2 {
    font-size: 1.75rem;
  }

  .cta-card .row {
    text-align: center;
  }

  .cta-card .btn-light {
    margin-top: 1.5rem;
  }

  .course-tabs {
    flex-direction: column;
  }

  .course-tabs .nav-link {
    width: 100%;
  }
}

@media (max-width: 575px) {
  .hero-title {
    font-size: 1.75rem;
  }

  .feature-card,
  .course-card,
  .professor-card {
    margin-bottom: 1.5rem;
  }
}

/* ========================================
   Scroll Animations
======================================== */
[data-aos] {
  pointer-events: none;
}

[data-aos].aos-animate {
  pointer-events: auto;
}

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

::-webkit-scrollbar-track {
  background: var(--gray-light);
}

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

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-blue-dark);
}