body {
    background: url('https://noithatbinhminh.com.vn/wp-content/uploads/2022/12/background-xanh-duong-20.jpg') no-repeat center center fixed;
    background-size: cover;
    font-family: Arial, sans-serif; /* Chọn font cho trang web */
    margin: 0;
    padding: 0;
   
}

header {
    background: rgba(74, 144, 226, 0.8);
    color: white;
    text-align: center;
    padding: 50px 20px;
    border-bottom: 5px solid #469aee;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    border: 2px solid #003366;
    border-radius: 10px;
    margin: 20px;
}

nav {
    background-color: rgba(0, 51, 102, 0.9);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    border: 2px solid #003366;
    border-radius: 10px;
    margin: 20px;
}

nav ul {
    list-style: none;
    padding: 10px;
    text-align: center;
}

nav ul li {
    display: inline;
    margin-right: 20px;
}

nav ul li a {
    color: white;
    text-decoration: none;
    padding: 10px 15px;
    border-radius: 5px;
    transition: background-color 0.3s, transform 0.2s;
}

nav ul li a:hover {
    background-color: #4A90E2;
    transform: scale(1.05);
}

.content-section {
    background-color: white;
    padding: 30px;
    margin: 20px 0;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    border: 2px solid #4A90E2;
}

.profile-image {
    border-radius: 50%;
    width: 150px;
    height: 150px;
    object-fit: cover;
    margin: 20px 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

footer {
    text-align: center;
    padding: 15px;
    background-color: rgba(0, 51, 102, 0.9);
    color: white;
    border: 2px solid #003366;
    border-radius: 10px;
    box-shadow: 0 -2px 5px rgba(0, 0, 0, 0.1);
}