I am using jQuery Colorbox with Advanced Responsive Video Embedder to embed YouTube videos. When I resize the browser to a smaller width, or view on a mobile device in portrait orientation, the Colorbox does not resize to the same proportions as the video inside it. The video resizes to the correct proportions in relationship to the width of the browser, but the Colorbox remains stretched to full height, leaving large black spaces above and below the video. I set all height and width settings to 80%. What is the best way to get the Colorbox height to resize in proportion to the width?