css media query
/* BOOSTRAP MEDIA BREAKPOINTS */
/* Small devices (landscape phones, 576px and up) */
@media (min-width: 576px) {
.selector {
background-color:#f00;
}
}
/* Medium devices (tablets, 768px and up) The navbar toggle appears at this breakpoint */
@media (min-width: 768px) {}
/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {}
/* Extra large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {}