@media all and (max-width:800px) code example
Example: media query min and max
/* Max-width */
@media only screen and (max-width: 600px) {...}
/* Min-width */
@media only screen and (min-width: 600px) {...}
/* Combining media query expressions */
@media only screen and (max-width: 600px) and (min-width: 400px) {...}