Adding Dimensions

To make a sidebar you can add a width:

width: 500px;

If you have an image, for example, you can use a percentage. 100%, would be 100 percent of the parent container (i.e. computer screen, tablet screen, or phone screen). Great when you are building websites that adapt to the screen width.

.author-img {
    width: 100%;
    height: auto;
}

Use “auto” in CSS if you have a width or height that you want to keep the aspect ratio, and you have width and height numbers in your HTML file. CSS will overwrite your HTML numbers.