.embed-container { 
        position: relative; 
        padding-bottom: 56.25%; 
        height: 0; 
        overflow: hidden; 
        max-width: 100%; } 

    .embed-container iframe, .embed-container object, .embed-container embed { 
        position: absolute; 
        top: 0; 
        left: 0; 
        width: 100%; 
        height: 100%; }