body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    color: #333;
}

header {
    background-color: #333;
    color: #fff;
    padding: 1rem 0;
    text-align: center;
}

nav ul {
    list-style: none;
    padding: 0;
    display: flex;
    justify-content: center;
}

nav ul li {
    margin: 0 15px;
}

nav ul li a {
    color: #fff;
    text-decoration: none;
    font-weight: bold;
}

.hero {
    background: url('https://via.placeholder.com/1500x500?text=Sua+Imagem+Principal+Aqui') no-repeat center center/cover;
    color: #fff;
    text-align: center;
    padding: 100px 20px;
}

.btn {
    background-color: #007bff;
    color: #fff;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
    display: inline-block;
    margin-top: 20px;
}

section {
    padding: 50px 20px;
    text-align: center;
}

.plans .card {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 20px;
    margin: 20px;
    display: inline-block;
    width: 300px;
    vertical-align: top;
}