Check out example codes for "css different sreen size". It will help you in understanding the concepts better.

Code Example 1

/* 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;
    }
}

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