```css
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
  scroll-behavior: smooth;
}

/* NAVBAR */
.navbar {
  display: flex;
  justify-content: space-between;
  padding: 15px 40px;
  background: #0f172a;
  color: white;
  position: sticky;
  top: 0;
}

.navbar nav a {
  color: white;
  margin-left: 20px;
  text-decoration: none;
}

.menu-toggle {
  display: none;
  font-size: 25px;
  cursor: pointer;
}

/* HERO */
.hero {
  height: 100vh;
  background: linear-gradient(rgba(0,0,0,0.6),rgba(0,0,0,0.6)),
  url('Images/classroom.jpeg') center/cover;
  display: flex;
  justify-content: center;
  align-items: center;
  text-align: center;
  color: white;
}

.hero h1 {
  font-size: 55px;
  animation: fadeIn 2s;
}

.btn {
  padding: 10px 25px;
  background: orange;
  border-radius: 5px;
  margin-top: 20px;
  display: inline-block;
}

/* COURSES */
.courses {
  padding: 60px;
  text-align: center;
}

.course-container {
  display: flex;
  justify-content: center;
  gap: 25px;
}

.card {
  padding: 25px;
  width: 250px;
  background: white;
  border-radius: 15px;
  box-shadow: 0 5px 20px rgba(0,0,0,0.1);
  transition: 0.4s;
}

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

/* GALLERY */
.gallery {
  padding: 50px;
  text-align: center;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 15px;
}

.gallery img {
  width: 100%;
  border-radius: 10px;
  transition: 0.3s;
}

.gallery img:hover {
  transform: scale(1.1);
}

/* CONTACT */
.contact {
  padding: 50px;
  text-align: center;
  background: #0f172a;
  color: white;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-width: 400px;
  margin: auto;
}

.contact-form input,
.contact-form textarea {
  padding: 10px;
  border-radius: 5px;
  border: none;
}

.contact-form button {
  background: orange;
  padding: 10px;
  border: none;
  color: white;
}

/* WHATSAPP */
.whatsapp {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: green;
  color: white;
  padding: 15px;
  border-radius: 50%;
  text-decoration: none;
}

/* FOOTER */
footer {
  text-align: center;
  padding: 15px;
  background: black;
  color: white;
}

/* ANIMATION */
@keyframes fadeIn {
  from {opacity: 0;}
  to {opacity: 1;}
}

/* MOBILE */
@media(max-width:768px){
  .course-container {
    flex-direction: column;
  }

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

  .menu-toggle {
    display: block;
  }

  nav {
    display: none;
    flex-direction: column;
    background: #0f172a;
    position: absolute;
    top: 60px;
    right: 0;
    padding: 10px;
  }

  nav.active {
    display: flex;
  }
}
```