885: CSS Fonts Fallbacks, Variable and Trimming

Update: 2025-03-17

Digest

This podcast episode delves into the world of advanced web fonts and CSS techniques for optimizing font rendering and layout. It begins with an introduction to web fonts and their evolution, then dives into the `@font-face` rule for embedding custom fonts and the crucial `font-display` property for managing font loading and minimizing cumulative layout shift (CLS). The episode then explores the power of variable fonts, showcasing their ability to dynamically adjust font attributes like weight and style using `font-variation-settings`, and introduces tools like Wakame Font to simplify their management. Finally, it covers the new CSS properties `text-box-trim` and `text-box-edge`, offering precise control over text box spacing and addressing issues with ascenders and descenders, particularly beneficial for button design. Browser support for these newer features is also discussed.

Outlines

00:00:00

Introduction to Web Fonts and Advanced Features

This introductory section covers the evolution of web fonts and previews advanced features like `@font-face`, `font-display`, variable fonts, `text-box-trim`, and `text-box-edge`, highlighting their impact on web design and performance.

00:02:53

Custom Fonts and Font Loading Optimization

This section details the use of `@font-face` for custom font embedding and the importance of the `font-display` property to manage font loading behavior (auto, block, swap, fallback) and minimize CLS. Strategies for avoiding jarring transitions are also discussed.

00:10:48

Variable Fonts and CSS Control

A deep dive into variable fonts, their capabilities (adjusting weight, italics, glyphs), and the `font-variation-settings` CSS property. Tools like Wakame Font for managing variable fonts are also mentioned.

00:19:11

Precise Text Box Control with New CSS Properties

This section introduces `text-box-trim` and `text-box-edge` for precise control over text box spacing, addressing issues with ascenders, descenders, and line heights, especially relevant for button design. Browser compatibility is discussed.

Keywords

`@font-face`

CSS rule for embedding custom fonts, enhancing design flexibility. Requires font file paths and fallbacks.

`font-display`

CSS property controlling font loading behavior (auto, block, swap, fallback), impacting visual rendering and CLS.

Variable Fonts

Font format enabling dynamic adjustments of font attributes (weight, width, slant) via CSS, offering smoother transitions and reduced file size.

Cumulative Layout Shift (CLS)

Web performance metric measuring unexpected layout changes; poor font loading contributes to CLS.

`font-variation-settings`

CSS property to control specific attributes within variable fonts, enabling fine-grained adjustments.

`text-box-trim`

New CSS property to trim extra whitespace above or below text, improving layout precision, especially for buttons.

`text-box-edge`

CSS property specifying the alignment of trimmed text within a text box, working with `text-box-trim`.

Wakame Font

Tool for managing and exploring variable font options.

Web Fonts

Digital fonts used on websites, offering diverse typographic choices.

Q&A

What is the `font-display` property and why is it important?
`font-display` controls browser font loading behavior. Options like `swap` and `fallback` minimize visual disruption, improving user experience.
How do variable fonts improve web performance?
Variable fonts dynamically adjust attributes in a single file, reducing file size and loading times compared to multiple font files.
What are `text-box-trim` and `text-box-edge`, and how do they help with layout?
These CSS properties provide precise control over vertical spacing in text boxes by trimming excess space caused by ascenders and descenders, improving layout consistency.
What tools can assist in working with variable fonts?
Tools like Wakame Font help manage and explore variable font options, simplifying implementation and customization.

Show Notes

Scott and Wes dig into the wild world of CSS fonts—covering fallbacks, variable fonts, and new tricks like text-box-trim. They also break down font-display, font kits, and how to avoid layout shifts when loading custom type.

Show Notes