Lesson {{curLesson+1}} of {{numOfLessons()}}

Percentage of screen dimensions

1vw means "1% of the viewport width", i.e., 1% of the browser's width.

Analogously, 1vh means "1% of the viewport height".

Minimum screen dimension

1vmin means "1% of the smallest viewport dimension", whether it is the width or the height. In cellphones, for example, it will most probably be the width.

Analogously, 1vmax means "1% of the largest viewport dimension".

{{getTitle()}}

https://www.css-demo/viewport-relative-units.com

You did it!

CSS Viewer
styles.css
div {
background: red;
width: {{widthPercentage}}vw;
height: {{heightPercentage}}vh;
}

body {
margin: 0;
}
div {
background: red;
width: {{widthPercentage}}vmin;
height: {{heightPercentage}}vmin;
}

body {
margin: 0;
}
HTML Viewer
index.html
<div></div>