CSS: define media query within one class [closed]

Answer 1

You should do like this:

@media all and (max-width: 767px) {
    .global-container {
        margin-top: 0;
        background-image: none;
    }
}

If you want to target desktop, you can use:

@media (min-width:1025px) { 
    .global-container {
        margin-top: 0;
        background-image: none;
    }
}

I just notice you're using SASS, you can do like this:

.global-container {
    margin-top: 60px;
    background-image: $image-bg;
    @media (max-width: 767px) {
        /* Your mobile styles here */
    }
    @media (min-width:1025px) {
        /* Your desktop styles here */
    } 
}