@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

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

body {
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
  color: #1f2937;
  overflow-x: hidden;
}

/* Custom Cursor */
.cursor {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: linear-gradient(45deg, #3b82f6, #8b5cf6);
  position: fixed;
  pointer-events: none !important;
  z-index: 9999;
  transition: transform 0.1s ease;
  mix-blend-mode: difference;
}

.cursor-follower {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 2px solid rgba(59, 130, 246, 0.3);
  position: fixed;
  pointer-events: none !important;
  z-index: 9998;
  transition: all 0.3s ease;
  backdrop-filter: blur(2px);
}

/* Animated Gradients */
@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.gradient-animated {
  background: linear-gradient(-45deg, #3b82f6, #8b5cf6, #06b6d4, #10b981);
  background-size: 400% 400%;
  animation: gradientShift 6s ease infinite;
}

/* Glassmorphism Effects */
.glass-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  border: 2px solid #3b82f6;
  border-radius: 24px;
  box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.18);
  transition: box-shadow 0.3s, border-color 0.3s;
}

.glass-card:focus,
.glass-card:hover {
  border-color: #8b5cf6;
  box-shadow: 0 16px 48px 0 rgba(59, 130, 246, 0.18);
}
/* Glassmorphism Effects */
.glass {
  background: rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
}

.glass-hover {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.glass-hover:hover {
  background: rgba(255, 255, 255, 0.35);
  transform: translateY(-5px);
  box-shadow: 0 20px 40px 0 rgba(31, 38, 135, 0.2);
}

/* Enhanced Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translate3d(0, 100px, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

/* ===== Responsive PDF Embed ===== */
.pdf-embed-wrapper {
  width: 100%;
  height: 80vh;
  background: #f9fafb;
}
.pdf-frame {
  width: 100%;
  height: 100%;
  border: 0;
}

/* ===== Mobile improvements ===== */
@media (max-width: 768px) {
  .pdf-embed-wrapper {
    height: calc(100vh - 180px); /* leave space for header/buttons */
  }

  /* Make tables horizontally scrollable on small screens */
  .responsive-table,
  .table-responsive {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .responsive-table table,
  .table-responsive table {
    min-width: 600px; /* prevent columns from squishing */
  }

  /* Ensure iframes and images never overflow */
  iframe, img, video {
    max-width: 100%;
  }

  /* Utility: stack action buttons */
  .btn-stack-sm > * {
    width: 100%;
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translate3d(-100px, 0, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translate3d(100px, 0, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

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

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes glow {
  0%, 100% { 
    box-shadow: 0 0 5px rgba(59, 130, 246, 0.5);
  }
  50% { 
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.8), 0 0 30px rgba(139, 92, 246, 0.6);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.6s ease-out forwards;
}

.animate-slide-in-left {
  animation: slideInLeft 0.6s ease-out forwards;
}

.animate-slide-in-right {
  animation: slideInRight 0.6s ease-out forwards;
}

.animate-float {
  animation: float 3s ease-in-out infinite;
}

.animate-pulse-scale {
  animation: pulse 2s ease-in-out infinite;
}

.animate-glow {
  animation: glow 2s ease-in-out infinite;
}

/* Parallax Backgrounds */
.parallax-bg {
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
  position: relative;
}

.parallax-bg::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(139, 92, 246, 0.1));
  z-index: 1;
}

.parallax-content {
  position: relative;
  z-index: 2;
}

/* Enhanced Navigation */
nav {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  transition: all 0.3s ease;
}

nav.scrolled {
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.nav-link {
  position: relative;
  transition: all 0.3s ease;
}

.nav-link::before {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #3b82f6, #8b5cf6);
  transition: width 0.3s ease;
}

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

/* Interactive Buttons */
.btn {
  position: relative;
  overflow: hidden;
  border-radius: 12px;
  transition: all 0.3s ease;
  background: linear-gradient(135deg, #3b82f6, #1d4ed8);
  border: none;
  color: white;
  font-weight: 600;
  letter-spacing: 0.025em;
}

.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 0.5s;
}

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

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 20px 40px rgba(59, 130, 246, 0.4);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.9);
  color: #3b82f6;
  border: 1px solid rgba(59, 130, 246, 0.3);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 1);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

/* Enhanced Cards */
.card {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 20px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.5), transparent);
  transform: translateX(-100%);
  transition: transform 0.6s ease;
}

.card:hover::before {
  transform: translateX(100%);
}

.card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: 
    0 25px 50px rgba(0, 0, 0, 0.15),
    0 0 0 1px rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.9);
}

.course-card {
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.course-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.05), rgba(139, 92, 246, 0.05));
  opacity: 0;
  transition: opacity 0.3s ease;
}

.course-card:hover::after {
  opacity: 1;
}

/* Magnetic Effect for Buttons */
.magnetic {
  transition: transform 0.2s ease;
}

/* Loading States */
.skeleton {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Progress Indicators */
.progress-bar {
  background: linear-gradient(90deg, #3b82f6, #8b5cf6, #06b6d4);
  background-size: 200% 100%;
  animation: progressFlow 2s linear infinite;
  border-radius: 10px;
  position: relative;
  overflow: hidden;
}

.progress-bar::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  animation: progressShine 1.5s ease-in-out infinite;
}

@keyframes progressFlow {
  0% { background-position: 0% 50%; }
  100% { background-position: 200% 50%; }
}

@keyframes progressShine {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

/* Interactive Elements */
.interactive-hover {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.interactive-hover:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

/* Scroll Animations */
.scroll-reveal {
  opacity: 0;
  transform: translateY(50px);
  transition: all 0.6s ease;
}

.scroll-reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* Modern Form Elements */
.form-input {
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: 12px;
  padding: 16px 20px;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.form-input:focus {
  background: rgba(255, 255, 255, 0.95);
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  transform: translateY(-2px);
}

/* Notification Styles */
.notification {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  transform: translateX(100%);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.notification.show {
  transform: translateX(0);
}

.notification-success {
  border-left: 4px solid #10b981;
}

.notification-error {
  border-left: 4px solid #ef4444;
}

.notification-info {
  border-left: 4px solid #3b82f6;
}

/* Hero Section Enhancements */
.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Ccircle cx='30' cy='30' r='2'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  animation: float 20s ease-in-out infinite;
}

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

/* Feature Cards */
.feature-card {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 20px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg, transparent, rgba(59, 130, 246, 0.1), transparent);
  transform: rotate(45deg);
  transition: all 0.6s ease;
  opacity: 0;
}

.feature-card:hover::before {
  opacity: 1;
  transform: rotate(45deg) translate(50%, 50%);
}

.feature-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.12);
  border-color: rgba(59, 130, 246, 0.3);
}

/* Stats Section */
.stats-card {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.9), rgba(255, 255, 255, 0.7));
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 20px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.stats-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #3b82f6, #8b5cf6, #06b6d4);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.6s ease;
}

.stats-card:hover::after {
  transform: scaleX(1);
}

.stats-number {
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 800;
  font-size: 2.5rem;
}

/* Modal Enhancements */
.modal {
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(10px);
  transition: all 0.3s ease;
}

.modal-content {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 24px;
  box-shadow: 0 40px 80px rgba(0, 0, 0, 0.2);
  transform: scale(0.9);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.modal.show .modal-content {
  transform: scale(1);
}

/* Video Player Enhancements */
#video-container {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px);
  border-radius: 24px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.1);
  overflow: hidden;
}

/* Sidebar Enhancements */
.sidebar {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(30px);
  border-right: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 20px 0 40px rgba(0, 0, 0, 0.05);
}

.lecture-item, .note-item {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 12px;
  position: relative;
  overflow: hidden;
}

.lecture-item::before, .note-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.1), transparent);
  transition: left 0.5s ease;
}

.lecture-item:hover::before, .note-item:hover::before {
  left: 100%;
}

.lecture-item:hover, .note-item:hover {
  transform: translateX(8px);
  background: rgba(59, 130, 246, 0.05);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

/* Search Input */
#content-search {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: 12px;
  transition: all 0.3s ease;
}

#content-search:focus {
  background: rgba(255, 255, 255, 0.98);
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Floating Controls */
.floating-controls {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.floating-controls button {
  transition: all 0.3s ease;
  border-radius: 12px;
}

.floating-controls button:hover {
  background: rgba(59, 130, 246, 0.1);
  transform: scale(1.1);
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .card {
    border-radius: 16px;
  }
  
  .feature-card {
    border-radius: 16px;
  }
  
  .stats-card {
    border-radius: 16px;
  }
}

/* Dark Theme Support (for future use) */
@media (prefers-color-scheme: dark) {
  body {
    background: #0f1419;
    color: #ffffff;
  }
  
  .glass {
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .card {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
  }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(135deg, #1d4ed8, #7c3aed);
}

/* Smooth Scroll */
html {
  scroll-behavior: smooth;
}

/* Text Selection */
::selection {
  background: rgba(59, 130, 246, 0.2);
  color: #1d4ed8;
}

/* Focus States */
*:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

/* Print Styles */
@media print {
  .glass, .card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
  }
}



/* Force modal text to black for visibility */
.modal-content, .modal-content label, .modal-content input, .modal-content span, .modal-content p, .modal-content a, .modal-content h1, .modal-content h2, .modal-content h3, .modal-content h4, .modal-content h5, .modal-content h6 {
  color: #111 !important;
}

/* Ensure modal text stays black on hover/focus/active */
.modal-content *,
.modal-content *:hover,
.modal-content *:focus,
.modal-content *:active {
  color: #000 !important;
  text-shadow: none !important;
  -webkit-text-fill-color: #000 !important;
}