@media (min-width: 1200px) {

    body {
      width: 100% !important;
      height: 100% !important;
      margin: 0;
      font-family: 'Roboto', sans-serif;
      font-size: 16px;
      font-weight: 100;
      color: #555;
      line-height: 30px;
      text-align: center;
}

h1, h2 {
	margin-top: 10px;
	font-size: 38px;
    font-weight: 100;
    color: #555;
    line-height: 50px;
}

h3 {
	font-size: 22px;
    color: #555;
    line-height: 30px;
}

h4 {
    font-size: 16px;
    font-weight: 100;
    color: #555;
    line-height: 20px;
}

h5 {
    font-size: 11px;
    font-weight: 100;
    color: #555;
    line-height: 7px;
}

a.martel {
    color: #fff;
}

a.martel:hover {
    color: #c72c2f;
}

a.martel:visited {
    color: #fff;
}

nav {
    width: 100%;
    margin: 0;
    padding: 10px 100px;
    color: #ffffff;
    vertical-align: middle;
    background: #000;
}

#logo {
    background-image: url(../images/Ceramique-S-Martel_Logo.png);
    width: 350px;
    height: 100px;
    float: left;
    text-indent: -9999px;
    display: block;
    margin: -5px;
}

.fond-marbre {
    background-image: url(../images/marbre.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 30px;
}

.blanc {
    width: 100%;
    height: auto;
    display: block;
    text-align: center;
    margin-right: auto;
    margin-left: auto;
    padding: 50px;
    box-shadow: 0px 8px 15px #c5c5c5 inset;
}

.noir {
    background-color: #000;
    padding: 20px 0px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    color: #fff;
    font-size: 15px;
}

.tx-rouge {
    color: #c72c2f;
}

.check-rouge {
    color: #c72c2f;
    font-size: 13px;
}

.tx-copyright {
    color: #c5c5c5;
    font-size: 12px;
}

.tx-centre {
    text-align: center;
}
    
    .tx-centre-gras {
        text-align: center;
        font-weight: bolder;
    }

a.leg {
    color: #c5c5c5;
}

a.leg:hover {
    color: #c72c2f;
}

a.leg:visited {
    color: #c5c5c5;
}

h1.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    margin-bottom: 30px;
    font-size: 50px;
}

h2.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    font-size: 40px;
    color: #c72c2f;
}

.partenaire img {
    -webkit-filter: grayscale(100%) opacity(30%); /* Safari 6.0 - 9.0 */
    filter: grayscale(100%) opacity(30%);
    vertical-align: middle;
}

.partenaire img:hover {
    -webkit-filter: grayscale(0%) opacity(100%); /* Safari 6.0 - 9.0 */
    filter: grayscale(0%) opacity(100%);
}

#contenu {
    margin-top: 100px;
    padding-left: 110px;
    padding-right: 110px;
    text-align: justify;   
}


#photo {
    display: block;
    float: right;
    margin-left: 40px;
}

.texte {
    text-align: right;
}

.centre {
    text-align: center;
}

}


<!--    -->

@media (min-width: 992.01px) and (max-width: 1199.98px) {
    
nav {
    margin: 0;
    padding: 0px;
    background: #000;
    vertical-align: middle;
}

#logo {
    background-image: url(../images/Ceramique-S-Martel_Logo2.png);
    width: 263px;
    height: 75px;
    float: left;
    text-indent: -9999px;
    display: block;
    margin-top: 7px;
    background-repeat: no-repeat;
}

.fond-marbre {
    background-image: url(../images/marbre.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 30px;
}

.blanc {
    width: 100%;
    height: auto;
    display: block;
    text-align: center;
    margin-right: auto;
    margin-left: auto;
    padding: 50px;
    box-shadow: 0px 8px 15px #c5c5c5 inset;
}

.noir {
    background-color: #000;
    padding: 20px 0px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    color: #fff;
    font-size: 15px;
}

.tx-rouge {
    color: #c72c2f;
}
    
#contenu {
    margin-top: 91px;
    padding-left: 50px;
    padding-right: 50px;
    text-align: justify;   
}

a.martel {
    color: #fff;
}

a.martel:hover {
    color: #c72c2f;
}

a.martel:visited {
    color: #fff;
}

.check-rouge {
    color: #c72c2f;
    font-size: 13px;
}
    

h1.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    margin-bottom: 30px;
    font-size: 50px;
}

h2.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    font-size: 40px;
    color: #c72c2f;
}

    
}
    
    
    
<!--    -->
    
@media (min-width: 768px) and (max-width: 992px) {
    
#logo {
    background-image: url(../images/Ceramique-S-Martel_Logo2.png);
    width: 263px;
    height: 75px;
    float: left;
    text-indent: -9999px;
    display: block;
    background-repeat: no-repeat;
    margin-top: 6px;
}
    
nav {
    margin: 0;
    padding: 0px;
    background: #000;
    vertical-align: middle;
}
    
#contenu {
    margin-top: 91px;
    padding-left: 30px;
    padding-right: 30px;
    text-align: justify;   
}

    
#photo {
    float:none;
    margin: 0px;
}
    
.texte {
    text-align: left;
}
    
a.martel {
    color: #fff;
}

a.martel:hover {
    color: #c72c2f;
}

a.martel:visited {
    color: #fff;
}
    
.check-rouge {
    color: #c72c2f;
    font-size: 13px;
}
    

.fond-marbre {
    background-image: url(../images/marbre.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 30px;
}

.blanc {
    width: 100%;
    height: auto;
    display: block;
    text-align: center;
    margin-right: auto;
    margin-left: auto;
    padding: 50px;
    box-shadow: 0px 8px 15px #c5c5c5 inset;
}

.noir {
    background-color: #000;
    padding: 20px 0px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    color: #fff;
    font-size: 15px;
}

.tx-rouge {
    color: #c72c2f;
}
  

h1.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    margin-bottom: 30px;
    font-size: 50px;
}

h2.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    font-size: 40px;
    color: #c72c2f;
}


    }
    
    
    
<!--    -->
    
@media (min-width: 576px) and (max-width: 767.98px) {
#logo {
    background-image: url(../images/Ceramique-S-Martel_Logo2.png);
    width: 263px;
    height: 75px;
    float: left;
    text-indent: -9999px;
    display: block;
    background-repeat: no-repeat;
    margin-top: 7px;
}
    
nav {
    margin: 0;
    padding: 0px;
    background: #000;
    vertical-align: middle;
}
    
#contenu {
    margin-top: 90px;
    padding-left: 10px;
    padding-right: 10px;
    text-align: justify;   
}

    
#photo {
    float:none;
    margin: 0px;
}
    
.texte {
    text-align: left;
}
    
a.martel {
    color: #fff;
}

a.martel:hover {
    color: #c72c2f;
}

a.martel:visited {
    color: #fff;
}
    
.check-rouge {
    color: #c72c2f;
    font-size: 13px;
}
    

.fond-marbre {
    background-image: url(../images/marbre.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 30px;
}

.blanc {
    width: 100%;
    height: auto;
    display: block;
    text-align: center;
    margin-right: auto;
    margin-left: auto;
    padding: 50px;
    box-shadow: 0px 8px 15px #c5c5c5 inset;
}

.noir {
    background-color: #000;
    padding: 20px 0px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    color: #fff;
    font-size: 15px;
}

.tx-rouge {
    color: #c72c2f;
}
    

h1.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    margin-bottom: 30px;
    font-size: 50px;
}

h2.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    font-size: 40px;
    color: #c72c2f;
}

    
}
    
    
    
<!--    -->
    
@media (max-width: 575.98px) {
#logo {
    background-image: url(../images/Ceramique-S-Martel_Logo3.png);
    width: 263px;
    height: 75px;
    float: left;
    text-indent: -9999px;
    display: block;
    background-repeat: no-repeat;
    vertical-align: middle;
    margin-top: 5px;
}
    
nav {
    margin: 0;
    padding: 0px;
    background: #000;
    vertical-align: middle;
}

#contenu {
    margin-top: 83px;
    padding-left: 5px;
    padding-right: 5px;
    text-align: justify;   
}

#photo {
    float:none;
    margin: 20px;
}
    
.texte {
    text-align: center;
}
    
#contenu {
    padding-left: 5px;
    padding-right: 5px;   
}
    
a.martel {
    color: #fff;
}

a.martel:hover {
    color: #c72c2f;
}

a.martel:visited {
    color: #fff;
}   

.check-rouge {
    color: #c72c2f;
    font-size: 13px;
}
    

.fond-marbre {
    background-image: url(../images/marbre.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 30px;
}

.blanc {
    width: 100%;
    height: auto;
    display: block;
    text-align: center;
    margin-right: auto;
    margin-left: auto;
    padding: 50px;
    box-shadow: 0px 8px 15px #c5c5c5 inset;
}

.noir {
    background-color: #000;
    padding: 20px 0px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    color: #fff;
    font-size: 15px;
}

.tx-rouge {
    color: #c72c2f;
}
    

h1.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    margin-bottom: 30px;
    font-size: 50px;
}

h2.martel {
    font-family: 'Dancing Script', cursive;
    text-align: center;
    font-size: 40px;
    color: #c72c2f;
}

    }