body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}
header {
    background: #4CAF50;
    color: white;
    padding: 15px;
    text-align: center;
}
nav {
    display: flex;
    justify-content: center;
    background: #333;
}
nav a {
    color: white;
    padding: 14px 20px;
    text-decoration: none;
}
nav a:hover {
    background: #ddd;
    color: black;
}
.content {
    flex: 1;
    padding: 20px;
}
footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 10px;
}
.hidden {
    display: none;
}
.section img {
    max-width: 100%;
    height: auto;
    margin: 20px 0;
}
form {
    display: flex;
    flex-direction: column;
    max-width: 400px;
    margin: auto;
}
input, textarea {
    margin: 10px 0;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}
button {
    padding: 10px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}
button:hover {
    background-color: #45a049;
}