body{
    background: #fff;
    display: flex;
    flex-direction: column;
}

.titre-contact {
    margin: 50px 0 20px;
    text-align: center;
    font-size: 60px;
    color: #000;
}

.contact-sous-titre{
    font-weight: lighter;
    text-align: center;
    margin: 10px 0 70px;
}

.trois-contacts {
    width: 800px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
}

.box{
    width: 200px;
    text-align: center;
}

.box span {
    font-size: 20px;
}

.box img{
    display: block;
    margin: 0 auto 10px;
    width: 70px;
}

/* formulaire */

form{
   width: 900px;
   margin: 100px auto 50px;
   box-shadow: 0 10px 15px 5px rgba(0,0,0,0.2); 
   padding: 20px;
   border-radius: 5px;
}

form h2{
    text-align: center;
    font-size: 40px;
    margin: 10px 0 20px;
}

.label-input{
    display: block;
    margin: 10px 0 10px 10px;
    font-size: 20px;
}

.label-input:nth-child(1) {
    margin-top: 20px;
}

input[type="text"],
input[type="number"]{
    display: block;
    width: 90%;
    margin: 10px 10px 20px;
    padding: 12px;
    border-radius: 5px;
    font-size: 18px;
    border: 1px solid #000;
}

.titre-check{
    display: inline;
    font-size: 20px;
    padding: 0 10px;
}
.groupe-check{
    display: inline;
}

.labels-check{
    font-size: 18px;
}

input[type="checkbox"]{
    display: inline;
    border: none;
    margin-right: 20px;
    margin-left: 5px;
    border-radius: 2px;
}

label[for="txt"]{
    display: block;
    text-align: left;
    font-size: 22px;
    margin: 30px 10px 20px;
}

textarea{
    font-family: Open sans, Arial, Helvetica, sans-serif;
    display: block;
    width: 90%;
    height: 200px;
    margin: 10px 10px 20px;
    resize: none;
    font-size: 18px;
    padding: 18px;
    border: 1px solid #000;
}

form button{
    display: block;
    margin: 10px auto 20px;
    width: 200px;
    height: 40px;
    font-size: 20px;
    border: none;
    border: 1px solid #000;
    border-radius: 5px;
}

@media screen and (max-width:800px) {
    
    .titre-contact{
        margin: 30px 0 20px;
        font-size: 40px;
    } 

    .contact-sous-titre{
        margin: 0 20px 20px;
        font-size: 16px;
    }

    .trois-contacts{
        flex-direction: column;
        width: 90%;
        align-items: center;
        justify-content: space-between;
    }

    .box{
        margin: 20px 0;
    }

    .box img{
        width: 50px;
    }

    form{
        width: 90%;
        margin: 80px auto 50px;
    }

    form h2{
        font-size: 30px;
        margin: 10px 0 30px;
    }

    .groupe-check{
        display: block;
        margin: 10px 0 10px 10px;
        font-size: 20px;
    }

    textarea{
        width: 80%;
    }
    
    input[type="text"],
    input[type="number"]{
        width: 80%;
    }
}