responsive-mobile-first.css

/* Extra small devices (phones, 600px and down) */
@media only screen and (max-width: 600px) {
  //...
} 

/* Small devices (portrait tablets and large phones, 600px and up) */
@media only screen and (min-width: 600px) {
  //...
} 

/* Medium devices (landscape tablets, 768px and up) */
@media only screen and (min-width: 768px) {
  //...
} 

/* Large devices (laptops/desktops, 992px and up) */
@media only screen and (min-width: 992px) {
  //...
}

/* Extra large devices (large laptops and desktops, 1200px and up) */
@media only screen and (min-width: 1200px) {
  //...
}

///////////////////////////////////////////////////

/* Landscape */
@media only screen and (orientation: landscape) {
  // ...
}