media_screen

min-width   Правило применяется к браузеру, ширина которого больше значения, указанного в запросе.
max-width   Правило применяется к браузеру, ширина которого меньше значения, указанного в запросе.
min-height  Правило применяется к браузеру, высота которого больше значения, указанного в запросе.
max-height  Правило применяется к браузеру, высота которого меньше значения, указанного в запросе.
orientation=portrait    Правило применяется к браузеру, высота которого не меньше его ширины.
orientation=landscape   Правило применяется к браузеру, ширина которого больше высоты.
https://developers.google.com/web/fundamentals/design-and-ui/responsive/?hl=ru

/* monitors and laptops */
@media screen and (min-width: 1240px)  {}

/* tablet */
@media screen and (min-width: 1024px) and (max-width: 1240px)  {}

@media screen and (min-width: 768px) and (max-width: 1024px) {}

/* mobile */
@media screen and (max-width: 768px) {}

/* iPad in portrait & landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px)  {}

/* iPad in landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : landscape) {}

/* iPad in portrait */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : portrait) {}

/* Retina iPad in portrait & landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (-webkit-min-device-pixel-ratio: 2) {}

/* Retina iPad in landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : landscape)
and (-webkit-min-device-pixel-ratio: 2) {}

/* Retina iPad in portrait */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : portrait) and (-webkit-min-device-pixel-ratio: 2) {}

/* iPad 1 & 2 in portrait & landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (-webkit-min-device-pixel-ratio: 1){}

/* iPad 1 & 2 in landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : landscape) and (-webkit-min-device-pixel-ratio: 1)  {}

/* iPad 1 & 2 in portrait */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : portrait) and (-webkit-min-device-pixel-ratio: 1) {}

/* iPad mini in portrait & landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (-webkit-min-device-pixel-ratio: 1)  {}

/* iPad mini in landscape */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : landscape) and (-webkit-min-device-pixel-ratio: 1)  {}

/* iPad mini in portrait */
@media only screen and (min-device-width : 768px) and (max-device-width : 1024px) and (orientation : portrait) and (-webkit-min-device-pixel-ratio: 1)  {}

/* iPhone 5 in portrait & landscape */
@media only screen and (min-device-width : 320px) and (max-device-width : 568px) {}

/* iPhone 5 in landscape */
@media only screen and (min-device-width : 320px) and (max-device-width : 568px) and (orientation : landscape) {}

/* iPhone 5 in portrait */
@media only screen and (min-device-width : 320px) and (max-device-width : 568px) and (orientation : portrait) {}

/* iPhone 2G-4S in portrait & landscape */
@media only screen and (min-device-width : 320px) and (max-device-width : 480px) {}

/* iPhone 2G-4S in landscape */
@media only screen and (min-device-width : 320px) and (max-device-width : 480px) and (orientation : landscape) {}

/* iPhone 2G-4S in portrait */
@media only screen and (min-device-width : 320px) and (max-device-width : 480px) and (orientation : portrait) {}