Use any element to open the actual modal, e.g. a <button> or an <a> element and specify a unique ID.
The <div> with class="modal" is a container element for the modal and the div with class="modal-content" is where you put your modal content (headings, paragraphs, images, etc).
The <span> element with class="close" should be used to close the modal.
The .modal class represents the window BEHIND the actual modal box. The height and width is set to 100%, which should create the illusion of a background window.
Add a black background color with opacity.
Set position to fixed; meaning it will move up and down the page when the user scrolls.
It is hidden by default, and should be shown with a click of a button (we'll cover this later).
This is the actual modal box that gets focus. Do whatever you want with it. We have got you started with a border, some padding, and a background color. The margin: 15% auto is used to push the modal box down from the top (15%) and centering it (auto).
We also set the width to 400px - this could be more or less, depending on screen size. We will cover this later.
The close button is styled with a large font-size, a specific color and floats to the right. We have also added some styles that will change the color of the close button when the user moves the mouse over it.