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

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: #333;
  overflow-x: hidden;
}

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

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 2px 20px 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;
}

.logo {
  font-size: 1.8rem;
  font-weight: 800;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  cursor: pointer;
  transition: transform 0.3s ease;
}

.logo:hover {
  transform: scale(1.05);
}

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

.nav-links a {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  transition: all 0.3s ease;
  cursor: pointer;
  position: relative;
  padding: 0.5rem 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  transition: width 0.3s ease;
}

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

.nav-links a:hover,
.nav-links a.active {
  color: #667eea;
}
.sidebar{
  position: fixed;
  top: 0;
  right: 0;
  height: 100vh;
  display: none;
  width: 250px;
  z-index: 999;
  background-color: white;
  backdrop-filter: blur(10px);
  box-shadow: px 3px 5px rgba(0, 0, 0, 0.39);
  flex-direction: column;
  align-items: flex-start;
  justify-content: flex-start;
  /* display: block;   */
    }
    .sidebar li{
        width:100%;

    }
    .sidebar a{
        width:100%;
    }

.mobile-menu {
  display: none;
  flex-direction: column;
  cursor: pointer;
}

.mobile-menu span {
  width: 25px;
  height: 3px;
  background: #333;
  margin: 16px 24px;
  transition: all 0.3s ease;
}
.mobile-menu:hover {
  background-color: #555;
}

/* Section Base Styles */
.section {
  min-height: 100vh;
  display: none;
}

.section.active {
  display: block;
  animation: fadeIn 0.5s ease-in;
}

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

.floating-shapes {
  position: absolute;
  width: 100%;
  height: 100%;
  overflow: hidden;
}

.shape {
  position: absolute;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  animation: float 6s ease-in-out infinite;
}

.shape:nth-child(1) {
  width: 80px;
  height: 80px;
  top: 20%;
  left: 10%;
  animation-delay: 0s;
}

.shape:nth-child(2) {
  width: 120px;
  height: 120px;
  top: 60%;
  right: 10%;
  animation-delay: 2s;
}

.shape:nth-child(3) {
  width: 60px;
  height: 60px;
  top: 80%;
  left: 20%;
  animation-delay: 4s;
}

.hero-content {
  max-width: 800px;
  padding: 2rem;
  position: relative;
  z-index: 2;
}

.hero-title {
  font-size: 4rem;
  font-weight: 800;
  margin-bottom: 1rem;
  animation: fadeInUp 1s ease;
}

.hero-subtitle {
  font-size: 1.5rem;
  margin-bottom: 2rem;
  opacity: 0.9;
  animation: fadeInUp 1s ease 0.2s both;
}

.hero-description {
  font-size: 1.2rem;
  margin-bottom: 3rem;
  opacity: 0.8;
  animation: fadeInUp 1s ease 0.4s both;
}

.cta-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 1s ease 0.6s both;
}

.btn {
  padding: 1rem 2rem;
  border: none;
  border-radius: 50px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none;
  display: inline-block;
}

.btn-primary {
  background: white;
  color: #667eea;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

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

.btn-secondary:hover {
  background: white;
  color: #667eea;
  transform: translateY(-3px);
}

/* Features Section */
.features {
  padding: 5rem 2rem;
  background: #f8f9fa;
}

.features-container {
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #2c3e50;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: "";
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 2px;
}

.section-subtitle {
  font-size: 1.2rem;
  color: #6c757d;
  margin-bottom: 3rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

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

.feature-card {
  background: white;
  padding: 2.5rem 2rem;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
}

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

.feature-icon {
  font-size: 3rem;
  margin-bottom: 1.5rem;
  display: block;
}

.feature-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: #2c3e50;
}

.feature-description {
  color: #6c757d;
  line-height: 1.6;
}

/* About Section */
.about {
  padding: 5rem 2rem;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.about-container {
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
}

.team-intro {
  max-width: 800px;
  margin: 0 auto 4rem;
  font-size: 1.2rem;
  color: #495057;
  line-height: 1.8;
}

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

.team-member {
  background: white;
  padding: 2rem;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
}

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

.member-avatar {
  width: 100px;
  height: 100px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 50%;
  margin: 0 auto 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  color: white;
  font-weight: 700;
}

.member-name {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #2c3e50;
}

.member-role {
  color: #667eea;
  font-weight: 500;
  margin-bottom: 1rem;
}

/* Lesson Section */
.lesson-section {
  min-height: 100vh;
  padding: 6rem 2rem 2rem;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.lesson-container {
  max-width: 1000px;
  margin: 0 auto;
}

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

.lesson-title {
  font-size: 3rem;
  font-weight: 700;
  color: #2c3e50;
  margin-bottom: 1rem;
}

.lesson-subtitle {
  font-size: 1.3rem;
  color: #6c757d;
  margin-bottom: 2rem;
}

.lesson-progress {
  background: white;
  border-radius: 10px;
  padding: 1rem;
  margin-bottom: 2rem;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.progress-bar-container {
  background: #e9ecef;
  height: 8px;
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.lesson-progress-bar {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  height: 100%;
  border-radius: 4px;
  transition: width 0.3s ease;
  width: 20%;
}

.progress-text {
  text-align: center;
  font-weight: 600;
  color: #495057;
}

.lesson-content {
  background: white;
  border-radius: 20px;
  padding: 3rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  margin-bottom: 2rem;
}

.lesson-topic {
  font-size: 2rem;
  font-weight: 700;
  color: #2c3e50;
  margin-bottom: 2rem;
}

.lesson-text {
  font-size: 1.1rem;
  line-height: 1.8;
  color: #495057;
  margin-bottom: 2rem;
}

.lesson-highlight {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 1.5rem;
  border-radius: 15px;
  margin: 2rem 0;
}

.lesson-highlight h4 {
  font-size: 1.3rem;
  margin-bottom: 1rem;
}

.lesson-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn-lesson {
  padding: 0.8rem 1.5rem;
  border: none;
  border-radius: 25px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-lesson.primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.btn-lesson.secondary {
  background: #e9ecef;
  color: #495057;
}

.btn-lesson:hover {
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.btn-lesson:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Quiz Section */
.quiz-section {
  min-height: 100vh;
  padding: 6rem 2rem 2rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.quiz-container {
  background: white;
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  width: 100%;
  max-width: 700px;
  overflow: hidden;
}

.quiz-header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 2rem;
  text-align: center;
}

.quiz-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.quiz-subtitle {
  opacity: 0.9;
}

.quiz-progress-container {
  background: rgba(255, 255, 255, 0.2);
  height: 8px;
  border-radius: 4px;
  margin-top: 1rem;
  overflow: hidden;
}

.quiz-progress-bar {
  background: white;
  height: 100%;
  border-radius: 4px;
  transition: width 0.3s ease;
  width: 0%;
}

.quiz-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem 2rem;
  background: #f8f9fa;
  border-bottom: 1px solid #e9ecef;
}

.question-counter {
  font-weight: 600;
  color: #495057;
}

.timer {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: #dc3545;
}

.quiz-content {
  padding: 2rem;
}

.question {
  font-size: 1.3rem;
  font-weight: 600;
  color: #2c3e50;
  margin-bottom: 2rem;
  line-height: 1.5;
}

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

.option {
  background: #f8f9fa;
  border: 2px solid #e9ecef;
  border-radius: 12px;
  padding: 1.5rem;
  cursor: pointer;
  transition: all 0.3s ease;
}

.option:hover {
  border-color: #667eea;
  background: #f0f4ff;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(102, 126, 234, 0.2);
}

.option.selected {
  border-color: #667eea;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.option.correct {
  border-color: #28a745;
  background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
  color: white;
}

.option.incorrect {
  border-color: #dc3545;
  background: linear-gradient(135deg, #dc3545 0%, #e83e8c 100%);
  color: white;
}

.quiz-controls {
  padding: 2rem;
  text-align: center;
  border-top: 1px solid #e9ecef;
}

/* Results Section */
.results-section {
  min-height: 100vh;
  padding: 6rem 2rem 2rem;
  background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.results-container {
  background: white;
  border-radius: 20px;
  padding: 3rem;
  text-align: center;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
  max-width: 600px;
  width: 100%;
}

.results-icon {
  width: 100px;
  height: 100px;
  margin: 0 auto 2rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
  color: white;
}

.results-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #2c3e50;
}

.results-score {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 2rem;
  color: #28a745;
}

.results-details {
  background: #f8f9fa;
  border-radius: 15px;
  padding: 2rem;
  margin: 2rem 0;
}

.results-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

.stat {
  text-align: center;
}

.stat-value {
  font-size: 1.8rem;
  font-weight: 700;
  color: #2c3e50;
}

.stat-label {
  color: #6c757d;
  font-weight: 500;
  margin-top: 0.5rem;
}

.results-message {
  font-size: 1.1rem;
  color: #495057;
  line-height: 1.6;
  margin-top: 1rem;
}

.results-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 2rem;
}

/* Footer */
.footer {
  background: #2c3e50;
  color: white;
  padding: 3rem 2rem 2rem;
  text-align: center;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
}

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

.footer-section h3 {
  margin-bottom: 1rem;
  color: #ecf0f1;
}

.footer-section p,
.footer-section a {
  color: #bdc3c7;
  text-decoration: none;
  line-height: 1.6;
  cursor: pointer;
}

.footer-section a:hover {
  color: #667eea;
}

.footer-bottom {
  border-top: 1px solid #34495e;
  padding-top: 2rem;
  color: #bdc3c7;
}

/* Utility Classes */
.hidden {
  display: none !important;
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

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

/* Responsive Design */
@media (max-width: 900px) {
  .nav-links {
    display: none;
  }

  .mobile-menu {
    display: flex;
     background-color: transparent;
     flex-direction: column;
     justify-content: center;
     cursor: pointer;
  }

   .mobile-menu span {
    width: 25px;
    height: 3px;
    background: #000;
    margin: 4px 0;
    transition: 0.3s;
  }

  .sidebar {
    display: flex;
    position: fixed;
    top: 0;
    right: 0;
    flex-direction: column;
    background: linear-gradient(135deg, #40407a 0%, #421d97 100%);
    width: 350px;
    height: 100vh;
    padding: 2rem;
    box-shadow: -2px 0 10px rgba(0,0,0,0.1);
    z-index: 999;
  }

  .sidebar li {
    margin-bottom: 1.5rem;
    list-style-type: none;
  }

  .sidebar a {
    color: #fffdfd;
    font-weight: 600;
    text-decoration: none;

  }
  .hero-title {
    font-size: 2.5rem;
  }

  .hero-subtitle {
    font-size: 1.2rem;
  }

  .cta-buttons {
    flex-direction: column;
    align-items: center;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .team-grid {
    grid-template-columns: 1fr;
  }

  .lesson-content {
    padding: 2rem 1.5rem;
  }

  .lesson-controls {
    flex-direction: column;
  }

  .quiz-content {
    padding: 1.5rem;
  }

  .results-stats {
    grid-template-columns: 1fr 1fr;
  }

  .results-actions {
    flex-direction: column;
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

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

  .feature-card {
    padding: 2rem 1.5rem;
  }

  .team-member {
    padding: 1.5rem;
  }
}