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

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #f9fafb;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Navigation */
.navbar {
  background-color: white;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
}

.logo h1 {
  color: #2563eb;
  font-size: 1.5rem;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
  align-items: center;
}

.nav-menu a {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  transition: color 0.3s ease;
}

.nav-menu a:hover {
  color: #2563eb;
}

/* Dropdown Menu */
.dropdown {
  position: relative;
}

.dropdown-link {
  display: flex;
  align-items: center;
  cursor: pointer;
}

.dropdown-link::after {
  content: "▼";
  font-size: 0.7rem;
  margin-left: 0.5rem;
  transition: transform 0.3s ease;
}

.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background-color: white;
  list-style: none;
  border: 1px solid #e5e7eb;
  border-radius: 0.5rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  min-width: 200px;
  margin-top: 0.5rem;
}

.dropdown-menu li {
  padding: 0;
}

.dropdown-menu a {
  display: block;
  padding: 0.75rem 1rem;
  color: #333;
  text-decoration: none;
  transition: background-color 0.3s ease;
}

.dropdown-menu a:hover {
  background-color: #f0f9ff;
  color: #2563eb;
}

.dropdown:hover .dropdown-menu {
  display: block;
}

.dropdown:hover .dropdown-link::after {
  transform: rotate(180deg);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  background: none;
  border: none;
  cursor: pointer;
  gap: 0.4rem;
}

.menu-toggle span {
  width: 25px;
  height: 3px;
  background-color: #333;
  transition: all 0.3s ease;
}

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

.menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -7px);
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 80px 0;
  text-align: center;
}

.hero-content h2 {
  font-size: 1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 2px;
  opacity: 0.9;
  margin-bottom: 0.5rem;
}

.hero-content h3 {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.2;
}

.hero-content p {
  font-size: 1.1rem;
  max-width: 700px;
  margin: 0 auto 2rem;
  opacity: 0.95;
}

/* Newsletter Form */
.newsletter-form {
  display: flex;
  gap: 0.5rem;
  max-width: 500px;
  margin: 2rem auto 3rem;
  flex-wrap: wrap;
  justify-content: center;
}

.newsletter-form input {
  flex: 1;
  min-width: 250px;
  padding: 0.75rem 1rem;
  border: none;
  border-radius: 0.5rem;
  font-size: 1rem;
}

.newsletter-form button {
  padding: 0.75rem 2rem;
  background-color: white;
  color: #667eea;
  border: none;
  border-radius: 0.5rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.newsletter-form button:hover {
  background-color: #f0f9ff;
}

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

.feature {
  background-color: rgba(255, 255, 255, 0.1);
  padding: 2rem;
  border-radius: 1rem;
  backdrop-filter: blur(10px);
  transition: transform 0.3s ease;
}

.feature:hover {
  transform: translateY(-5px);
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

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

.feature p {
  font-size: 0.95rem;
  opacity: 0.9;
}

/* Footer */
.footer {
  background-color: #1f2937;
  color: white;
  padding: 3rem 0 1rem;
  margin-top: 4rem;
}

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

.footer-section h4 {
  margin-bottom: 1rem;
  color: #60a5fa;
}

.footer-section a {
  color: #d1d5db;
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-section a:hover {
  color: #60a5fa;
}

.footer-section ul {
  list-style: none;
}

.footer-section ul li {
  margin-bottom: 0.5rem;
}

.footer-bottom {
  border-top: 1px solid #374151;
  padding-top: 1.5rem;
  text-align: center;
  color: #9ca3af;
}

/* Course Cards Grid */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.course-card {
  background: white;
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  border-top: 4px solid #2563eb;
}

.course-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
}

.course-card h4 {
  color: #2563eb;
  margin-bottom: 1rem;
  font-size: 1.25rem;
}

.course-card p {
  color: #666;
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

/* Button Style */
.btn {
  display: inline-block;
  background-color: #2563eb;
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  text-decoration: none;
  font-weight: 600;
  transition: background-color 0.3s ease;
  border: none;
  cursor: pointer;
}

.btn:hover {
  background-color: #1d4ed8;
}

.btn-secondary {
  background-color: #667eea;
}

.btn-secondary:hover {
  background-color: #5568d3;
}

/* Course Detail Page */
.course-detail {
  background: white;
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  margin: 2rem 0;
}

.course-header {
  border-bottom: 2px solid #2563eb;
  padding-bottom: 2rem;
  margin-bottom: 2rem;
}

.course-header h2 {
  color: #2563eb;
  margin-bottom: 0.5rem;
  font-size: 2rem;
}

.course-header p {
  color: #666;
  font-size: 1.1rem;
}

.course-info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin: 2rem 0;
}

.info-box {
  background-color: #f3f4f6;
  padding: 1.5rem;
  border-radius: 0.75rem;
  border-left: 4px solid #2563eb;
}

.info-box h4 {
  color: #2563eb;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.info-box p {
  color: #333;
  font-size: 1.1rem;
  font-weight: 600;
}

.course-section {
  margin: 2rem 0;
}

.course-section h3 {
  color: #2563eb;
  margin-bottom: 1rem;
  font-size: 1.5rem;
  border-bottom: 2px solid #e5e7eb;
  padding-bottom: 0.75rem;
}

.course-section ul {
  list-style: none;
  margin-left: 0;
}

.course-section li {
  padding: 0.75rem 0;
  padding-left: 2rem;
  position: relative;
  color: #555;
}

.course-section li:before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #2563eb;
  font-weight: bold;
  font-size: 1.2rem;
}

.course-section p {
  color: #555;
  line-height: 1.8;
  margin-bottom: 1rem;
}

.back-link {
  display: inline-block;
  margin-bottom: 2rem;
  color: #2563eb;
  text-decoration: none;
  font-weight: 600;
}

.back-link:hover {
  text-decoration: underline;
}

/* Responsive Design */
@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }

  .nav-menu {
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background-color: white;
    flex-direction: column;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  }

  .nav-menu.active {
    max-height: 500px;
  }

  .nav-menu li {
    width: 100%;
  }

  .nav-menu a {
    display: block;
    padding: 1rem;
    border-bottom: 1px solid #f0f0f0;
  }

  .dropdown-menu {
    position: static;
    display: none;
    box-shadow: none;
    border: none;
    background-color: #f9fafb;
  }

  .dropdown.active .dropdown-menu {
    display: block;
  }

  .hero-content h3 {
    font-size: 2rem;
  }

  .newsletter-form {
    flex-direction: column;
  }

  .newsletter-form input,
  .newsletter-form button {
    width: 100%;
  }

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

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

  .course-header h2 {
    font-size: 1.5rem;
  }

  .course-info-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .hero-content h3 {
    font-size: 1.5rem;
  }

  .hero-content p {
    font-size: 0.95rem;
  }

  .feature-icon {
    font-size: 2rem;
  }
}