Only global apply styles

I’m trying to apply styles to pages but it’s not responding to any scss

only global.scss applying my styles

.postContent {

    line-height: 2 !important;

    font-size: 0.9em !important;

    -webkit-user-select: text;

    -moz-user-select: text;

    -ms-user-select: text;

    user-select: text;



        p,

        b,

        span,

        div,

        h1,

        h2,

        h3,

        h4,

        h5,

        h6 {

            font-size: 0.9em !important;

        }



    iframe {

        max-width: 92vw;

    }



}

any help?