media queries: problemi con min-device-width

[geggiamarti]

Ciao a tutti, sto avendo problemi con le media queries:

/* regole */
    
@media screen and (min-device-width: 400px) and (max-device-width: 500px), screen and (min-width: 400px) and (max-width: 500px){
    /* regole */
}
@media screen and (min-device-width: 500px) and (max-device-width: 600px), screen and (min-width: 500px) and (max-width: 600px){
    /* regole */
}
@media screen and (min-device-width: 600px) and (max-device-width: 700px), screen and (min-width: 600px) and (max-width: 700px){
    /* regole */
}
@media screen and (min-device-width: 700px) and (max-device-width: 800px), screen and (min-width: 700px) and (max-width: 800px){
    /* regole */
}
@media screen and (min-device-width: 800px) and (max-device-width: 900px), screen and (min-width: 800px) and (max-width: 900px){
    /* regole */
}
@media screen and (min-device-width: 900px) and (max-device-width: 1000px), screen and (min-width: 900px) and (max-width: 1000px){
    /* regole */
}
@media screen and (min-device-width: 1000px) and (max-device-width: 1100px), screen and (min-width: 1000px) and (max-width: 1100px){
    /* regole */
}
@media screen and (min-device-width: 1100px) and (max-device-width: 1200px), screen and (min-width: 1100px) and (max-width: 1200px){
    /* regole */
}
@media screen and (min-device-width: 1200px), screen and (min-width: 1200px){
    /* regole */
}

In pratica viene eseguita sempre l'ultima media query.... non ho idea del perché... ringrazio anticipatamente chi riesce a capirlo