if screen width is less than css code example
Example: css if screen size less than
@media (max-width:960px) { css... } //nothing with screen size bigger than 960px
@media (min-width:960px) { css... } //nothing with screen size smaller than 960px
@media (max-width:960px) { css... } //nothing with screen size bigger than 960px
@media (min-width:960px) { css... } //nothing with screen size smaller than 960px