media query not work code example

Example 1: why my media query is not working

<meta content="width=device-width, initial-scale=1" name="viewport" />

Example 2: css media query not working

.edcar_letter{
    font-size:180px;
}

@media screen and (max-width: 350px) {
    .edcar_letter{
        font-size:120px;
    }
}