How to find duplicates in code?

Question

NetBeans

Hello.
I was puzzled by such a question, maybe someone in the know ... I will be glad to help, recommendations.
I'm coding a little in netbeans and can't figure out how to find duplicates in the same file using netbeans itself. And then the file grows, and it’s not an option to search stupidly through the browser.
I mean like:

@media only screen and (orientation : portrait) and (min-width : 501px) and (max-width : 1024px){
    .logo{
        /*  background: red; */
        padding: 0 5px;
        margin: 0 0 0 5px;
        flex: 1 1 50px;
        order: 1;
    }
}
@media only screen and (orientation : portrait) and (min-width : 300px) and (max-width : 500px){
    .logo{
        /*  background: red; */
        padding: 0 5px;
        margin: 0 0 0 5px;
        flex: 1 1 50px;
        order: 1;
    }
}

After all, I want to do something like:

@media only screen and (orientation : portrait) and (min-width : 300px) and (max-width : 1024px){
    .logo{
        /*  background: red; */
        padding: 0 5px;
        margin: 0 0 0 5px;
        flex: 1 1 50px;
        order: 1;
    }
}