body {
  font-family: 'Segoe UI', sans-serif;
  margin:0; padding:0;
  background:#f4f4f9;
  color:#333;
}

header {
  background:#004466;
  color:white;
  text-align:center;
  padding:10px 0;
}

header nav a {
  color:white;
  text-decoration:none;
  margin:0 15px;
  padding:5px 10px;
  border-radius:4px;
}

header nav a.active {
  background:white;
  color:#004466;
}

.banner {
  width:100%;
  max-height:250px;
  object-fit:cover;
}

main {
  padding:20px;
  text-align:center;
}

.btn {
  display:inline-block;
  margin-top:10px;
  padding:10px 20px;
  background:#0088cc;
  color:white;
  text-decoration:none;
  border-radius:5px;
  cursor:pointer;
}

.courses, #adminCourses {
  display:flex;
  flex-wrap:wrap;
  justify-content:center;
  gap:20px;
  margin-top:20px;
}

.course-card, .admin-card {
  background:white;
  border-radius:8px;
  box-shadow:0 0 10px rgba(0,0,0,0.1);
  width:250px;
  padding:15px;
  text-align:left;
  position:relative;
}

.course-card img, .admin-card img {
  width:100%;
  border-radius:8px;
}

.admin-card button {
  background:#cc0000;
  color:white;
  border:none;
  padding:5px 10px;
  border-radius:4px;
  cursor:pointer;
  position:absolute;
  top:10px; right:10px;
}

input, textarea {
  width:100%;
  padding:8px;
  margin:5px 0 10px 0;
  border:1px solid #ccc;
  border-radius:4px;
}

footer {
  margin-top:20px;
  background:#222;
  color:white;
  text-align:center;
  padding:10px;
}