body{
    background-color:whitesmoke;
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
    box-sizing: border-box;
    max-width: 600px;
    margin: 20px auto;
    background-color: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

header, footer {
    background-color: #e42323;
    color: #fff;
    text-align: center;
    padding: 10px 0;
}

section {
    margin-bottom: 20px;
}

#add-book-form {
    text-align: center;
}

#search {
    text-align: center;
}

.hidden {
    display: none;
}