apply css only for mobile devices code example

Example 1: media query

@media only screen and (max-width: 600px) {
  body {
    background-color: lightblue;
  }
}

Example 2: css different sreen size

/* For Mobile */
@media screen and (max-width: 540px) {
    .view {
        width: 400px;
    }
}

/* For Tablets */
@media screen and (min-width: 540px) and (max-width: 780px) {
    .view {
        width: 600px;
    }
}