Book Image

Mastering Responsive Web Design

By : Ricardo Zea
Book Image

Mastering Responsive Web Design

By: Ricardo Zea

Overview of this book

Building powerful and accessible websites and apps using HTML5 and CSS3 is a must if we want to create memorable experiences for our users. In the ever-changing world of web design and development, being proficient in responsive web design is no longer an option: it is mandatory. Each chapter will take you one step closer to becoming an expert in RWD. Right from the start your skills will be pushed as we introduce you to the power of Sass, the CSS preprocessor, to increase the speed of writing repetitive CSS tasks. We’ll then use simple but meaningful HTML examples, and add ARIA roles to increase accessibility. We’ll also cover when desktop-first or mobile-first approaches are ideal, and strategies to implement a mobile-first approach in your HTML builds. After this we will learn how to use an easily scalable CSS grid or, if you prefer, how to use Flexbox instead. We also cover how to implement images and video in both responsive and responsible ways. Finally, we build a solid and elegant typographic scale, and make sure your messages and communications display correctly with responsive emails.
Table of Contents (16 chapters)
Mastering Responsive Web Design
About the Author
About the Reviewers

Calculating relative font sizes

Remember the RWD magic formula we mentioned in Chapter 3, Mobile-first or Desktop-first?:

(target ÷ context) x 100 = result %

There's also another similar magic formula to calculate relative font sizes (ems) when the font size has been set in pixels. The only difference is that we don't multiply by 100.

This is that formula:

target ÷ context = result

The target is the font size defined in pixels. The context is the font size defined in the parent container. The result is the value defined in ems.

Here's an example considering that the font size in the parent container, the body in this example, is 16px:

header {
    font: 30px Arial, "Helvetica Neue", Helvetica, sans-serif;

To calculate the relative font size, we use the following formula:

30px ÷ 16px = 1.875em.

So our CSS rule will look like this:

header {
    font: 1.875em Arial, "Helvetica Neue", Helvetica, sans-serif;

We would have to do this for every font size in our design.

This is fine in terms of understanding...