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


header {
    background-color: lightgreen;
    color: white;
    text-align: center;
    padding: 1em 0;
}


#Destinataire h2, #EnvoyerA h2 {
    color: #333;
}


#Destinataire, #EnvoyerA {
    background-color: #fff;
    padding: 1em;
    margin: 1em;
    border-radius: 5px;
    box-shadow: 0 0;
}
button{
    background-color: lightgreen;
    color: white;
    padding: 14px 20px;
    margin: 8px 0;
    border: none;
    cursor: pointer;
    width: 100%;
}
a{
    text-decoration: none;
}