Introduction to Animation on the Web

20 May 2024

Updated: 20 May 2024

ZOOOOOOM! ๐Ÿ”

Is everything big enough and are we in dark mode?

Housekeeping ๐Ÿงน

  • Everyone is encouraged to have their cameras on
  • Session will be recorded and made available by the learning team in a few weeks
  • Content will also be available on my website after the session
  • We will stop for questions along the way and should have some time at the end
  • Animations may be a bit laggy due to MS Teams

๐ŸŽž๏ธ Animation on the Web ๐ŸŒ

Nabeel Valley ๐Ÿค“

  • From Pretoria
  • Currently in NL
  • Full Stack Developer
  • @ Entelect since July 2023
  • On the Digital Platform team at Rabobank
  • Like making things
Nabeel Valley

Things โœŒ๏ธ Talk About

(the agenda)

  • Why do we need animations?
  • Animating in CSS
  • Principles of Animation
  • When to ignore all of this

Why do we need animations? ๐Ÿคท

  • User Feedback
  • Draw attention to something
  • Highlight personality
  • Juicyness

โ˜๏ธ A Quick Note on Custom Properties

These examples make extensive use of CSS Custom Properties so itโ€™s good to have a basic understanding of them

web-animations/custom-properties.css
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.my-stuff {
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/* def */
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--my-color: red;
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--my-size: 12px;
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/* use */
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background-color: var(--my-color);
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/* default */
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height: var(--my-size, 24px);
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width: var(--some-undefined-value, 24px);
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}

Animating in CSS ๐Ÿง‘โ€๐Ÿ’ป

  • Transitions
  • Keyframes
  • View Transitions
  • Optimizing Animations

Transitions ๐ŸŽข

  • Related to state changes
  • Control change of properties over time
  • Implicit transitions
    • Intermediate states defined by browser

Setting up a Transition ๐Ÿ”ง

We need something to animate

web-animations/index.html
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<div class="wrapper">
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<div class="greeting">
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Hi there
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<span class="hand">๐Ÿ‘‹</span>
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</div>
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</div>
web-animations/styles.css
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}

Using Transitions ๐Ÿ‘ท

Questions?

web-animations/transition-simple.css
15 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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transition-property: all;
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transition-duration: 300ms;
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transition-delay: 100ms;
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transition-timing-function: ease-in;
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}
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}

๐Ÿ“ Shorthand Syntax

web-animations/transition-simple-alt.css
16 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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/* shorthand */
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transition: all 300ms 100ms ease-in;
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}
6 collapsed lines
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}

Multi Property Transitions โ™พ๏ธ

web-animations/transition-properties.css
16 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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transition-property: transform, color, background-color;
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transition-duration: 300ms, 100ms, 100ms;
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transition-delay: 0ms, 300ms, 300ms;
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transition-timing-function: ease-in, ease-out, ease-in-out;
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}
6 collapsed lines
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}

๐Ÿค Multi Property Transition Shorthand

web-animations/transition-properties-alt.css
16 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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transition:
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transform 300ms 0ms ease-in,
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color 100ms 300ms ease-out,
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background-color 100ms 300ms ease-in-out;
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}
6 collapsed lines
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}

Combining Transitions ๐Ÿค

web-animations/transition-hand.css
29 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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transition:
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transform 300ms 0ms ease-in,
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color 100ms 300ms ease-out,
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background-color 100ms 300ms ease-in-out;
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}
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}
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.greeting .hand {
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transition: transform 100ms 0ms ease-out;
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transform-origin: bottom right;
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}
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.greeting:hover .hand {
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transition-duration: 300ms;
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transition-delay: 400ms;
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transform: rotate(30deg);
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}

Timing โฑ๏ธ Functions

web-animations/transition-timing.css
16 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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}
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.greeting {
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transition-property: color, transform;
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transition-duration: 1s;
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transition-timing-function: var(--timing-function);
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}
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.greeting:hover {
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transform: scale(1.2);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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}

โช Recap Transitions

  • Syntax for Transitions
  • Defining transitions based on DOM state
  • Transitioning multiple properties
  • Shorthand syntax
  • Combining transitions
  • Timing functions

Animations ๐ŸŽž๏ธ

  • Run as soon as the element or class is added
  • More complex animations possible
  • Can be independent of state
  • Implicit or Explicit
    • We can define intermediate states

Using Animations ๐Ÿ“น

Questions?

web-animations/animation-simple.css
12 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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transform-origin: bottom right;
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/* basic properties */
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animation-delay: 100ms;
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animation-duration: 500ms;
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animation-timing-function: ease-in-out;
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/* keyframes name */
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animation-name: hand-wave;
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/* iterations */
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animation-iteration-count: infinite;
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/* direction */
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animation-direction: alternate;
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/* completion state */
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animation-fill-mode: forwards;
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}
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@keyframes hand-wave {
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from {
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transform: rotate(0deg);
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}
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to {
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transform: rotate(30deg);
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}
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}

State Based Animations ๐Ÿ”›

web-animations/animation-hover.css
12 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
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display: inline-block;
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transform-origin: bottom right;
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animation-delay: 100ms;
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animation-duration: 500ms;
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animation-timing-function: ease-in-out;
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animation-name: hand-wave;
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animation-iteration-count: infinite;
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animation-direction: alternate;
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animation-fill-mode: both;
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/* state */
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animation-play-state: paused;
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}
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/* hover */
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.greeting:hover .hand {
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/* state */
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animation-play-state: running;
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}
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@keyframes hand-wave {
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from {
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transform: rotate(0deg);
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}
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to {
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transform: rotate(30deg);
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}
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}

Multi Property Animations ๐Ÿฟ

web-animations/animation-properties.css
12 collapsed lines
1
.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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}
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.hand {
7 collapsed lines
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display: inline-block;
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transform-origin: bottom right;
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/* basic properties */
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animation-duration: 1s;
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animation-iteration-count: infinite;
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/* multi */
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animation-name: hand-wave-multi;
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animation-play-state: paused;
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}
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.greeting:hover .hand {
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animation-play-state: running;
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}
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@keyframes hand-wave-multi {
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0% {
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transform: rotate(0deg);
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}
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15% {
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scale: 150%;
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transform: rotate(0deg);
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translate: 0px -8px;
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}
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50% {
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scale: 150%;
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transform: rotate(30deg);
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translate: 0px -8px;
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}
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85% {
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scale: 150%;
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transform: rotate(0deg);
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translate: 0px -8px;
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}
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100% {
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transform: rotate(0deg);
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}
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}

โช Recap - Animations

  • Syntax for Animations
  • Syntax for Keyframes
  • Defining animations based on DOM state
  • Animating multiple properties

View ๐Ÿ•ถ๏ธ Transitions

  • Triggered by JS
  • Transitions content as well as properties
  • Can be used across navigations (browser support in progress)

Triggering a Transition โœ…

Questions?

web-animations/ViewTransitions.astro
18 collapsed lines
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<script>
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const words = [
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"pale",
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"dangerous",
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"secret",
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"madly",
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"sharp",
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"mammoth",
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"overrated",
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"painful",
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"ill-informed",
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"dizzy",
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"ambitious",
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"stable"
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]
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const random = () => words[Math.floor(Math.random()*words.length)].toUpperCase();
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const handleWrapperClicked = (wrapper) => () => {
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// updateCallback
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document.startViewTransition(() => {
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const content = wrapper.querySelector('.view-transitions-content')
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content.classList.toggle('inverted')
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content.innerHTML = random()
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})
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}
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// wait for all snippets to initialize
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setTimeout(() => {
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const wrappers = document.querySelectorAll('.view-transitions-wrapper')
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for (const wrapper of wrappers) {
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// trigger
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wrapper.addEventListener('click', handleWrapperClicked(wrapper))
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}
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}, 1000)
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</script>
17 collapsed lines
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<style is:global>
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.view-transitions-wrapper {
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overflow: hidden;
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}
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.view-transitions-content {
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padding: 1rem;
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background-color: var(--color-brand);
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user-select: none;
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margin: 0;
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&.inverted {
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filter: invert();
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}
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}
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</style>

The Default Transition ๐Ÿ˜

  • 2 Different transitions
    • Fades old content out
    • Fades new content in
web-animations/view-transitions.html
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<div class="view-transitions-wrapper">
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<h1 class="view-transitions-content">CONTENT</h1>
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</div>

CONTENT

Understanding the Transition ๐Ÿค”

Questions?

web-animations/view-transitions-slide.css
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/* assign */
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.view-transitions-content {
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view-transition-name: content-transition;
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}
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/* old */
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::view-transition-old(content-transition) {
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animation: content-slide 0.5s linear;
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}
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/* new */
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::view-transition-new(content-transition) {
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animation: content-slide 0.5s linear reverse;
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}
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/* keyframes */
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@keyframes content-slide {
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0% {
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transform: scale(1);
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}
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15% {
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transform: translateY(0);
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}
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85% {
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transform: translateY(100%);
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opacity: 0;
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}
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100% {
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opacity: 0;
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transform: translateY(100%) scale(1);
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}
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}

โช Recap - View Transitions

  • Trigering a View Transition
  • The Default Transition
  • Customizing a Transitions

Animation Optimization โšก

  • Size changes are costly
  • Some properties are GPU accelearated
    • transform
    • filter
    • opacity
  • Using will-change
    • Last resort
    • Do not apply to too many elements

Premature optimization? Itโ€™s relatively easy to write it correctly first time

๐Ÿ”ฎ Will-Change

  • Used to inform the browser that certain elements of a property will be changed
  • The browser can use this to optimize the transition/animation of the property
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.greeting {
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will-change: transform;
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}

The 12 Principles of Animation ๐Ÿ“”

  • Introduced in โ€œThe Illusion of Lifeโ€ by Frank Thomas and Ollie Johnston

What do we do with our new found skills?

1. Squash and Stretch ๐Ÿชข

Illusion of weight and volume

web-animations/principles-1.css
37 collapsed lines
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.greeting {
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display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
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background-color: var(--color-brand-muted);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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color: transparent;
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margin-top: 200px;
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aspect-ratio: 1;
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}
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.wrapper {
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padding: 0px 100px;
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}
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.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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--timing-up: cubic-bezier(0.33333, 0.66667, 0.66667, 1);
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--timing-down: cubic-bezier(0.33333, 0, 0.66667, 0.33333);
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display: inline-block;
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animation-iteration-count: infinite;
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animation-duration: var(--duration-s);
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animation-direction: alternate;
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animation-name: greeting-1-move, greeting-1-squash;
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animation-timing-function: var(--timing-up);
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animation-composition: accumulate;
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will-change: transform;
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}
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@keyframes greeting-1-move {
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0% {
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transform: translateY(0px);
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}
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100% {
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transform: translateY(-200px);
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}
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}
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@keyframes greeting-1-squash {
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0% {
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transform: scaleY(0.5) scaleX(1.5);
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}
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20% {
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transform: scaleY(1.5) scaleX(0.5);
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}
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95% {
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transform: scaleY(1) scaleX(1);
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}
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100% {
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transform: scaleY(1) scaleX(1);
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}
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}

2. Anticipation โŒ›

Using small actions to indicate an action is about to happen

web-animations/principles-2.css
18 collapsed lines
1
.greeting {
2
display: inline-block;
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text-transform: lowercase;
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padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
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16 0,
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auto;
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color: transparent;
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aspect-ratio: 1;
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}
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.wrapper {
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padding: 0px 100px;
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}
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.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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display: inline-block;
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transition-property: transform;
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transition-duration: var(--duration-s);
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transition-timing-function: cubic-bezier(0.75, -0.61, 0.87, -0.16);
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}
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.wrapper:hover .greeting {
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transform: translateX(20vw);
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}

3. Follow Through and Overlap ๐Ÿพ

Adding movement after an action

web-animations/principles-3.css
16 collapsed lines
1
.greeting {
2
display: inline-block;
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text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
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color: var(--color-on-base);
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cursor:
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url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
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.hand {
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display: inline-block;
15
}
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.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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transition-property: all;
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transition-duration: var(--duration-s);
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transition-timing-function: ease-in-out;
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}
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.greeting:hover {
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background-color: var(--color-brand);
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color: var(--color-on-brand);
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animation-name: greeting-3;
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animation-duration: var(--duration-s);
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animation-delay: var(--duration-s);
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}
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@keyframes greeting-3 {
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0% {
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scale: 1;
36
}
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50% {
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scale: 1.1;
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}
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100% {
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scale: 1;
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}
45
}

4. Arcs โญ•

Nature moves in arcs

web-animations/principles-4.css
12 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
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cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.hand {
14
--duration-s: calc(var(--duration, 1) * 1s);
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display: inline-block;
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animation-duration: var(--duration-s);
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animation-iteration-count: infinite;
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animation-name: hand-wave-multi;
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animation-play-state: paused;
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transform-origin: 50px 50px;
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}
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.greeting:hover .hand {
25
animation-play-state: running;
26
}
27
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@keyframes hand-wave-multi {
29
0% {
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transform: rotate(0deg);
31
}
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15% {
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scale: 150%;
35
rotate: 0deg;
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translate: 0px -8px;
37
}
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50% {
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scale: 150%;
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rotate: 30deg;
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translate: 0px -8px;
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}
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85% {
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scale: 150%;
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rotate: 0deg;
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translate: 0px -8px;
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}
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100% {
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rotate: 0deg;
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}
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}

5. Slow In & Slow Out ๐Ÿฆฅ

Easing in and out of an action

web-animations/principles-5.css
12 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
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cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.hand {
14
display: inline-block;
15
}
16
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.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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transition-property: all;
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transition-duration: var(--duration-s);
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transition-timing-function: ease-in-out;
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}
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.greeting:hover {
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transform: scale(1.1);
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background-color: var(--color-brand);
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color: var(--color-on-brand);
29
}

6. Timing โŒš

Number of frames for a given action

web-animations/principles-6.css
19 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
cursor:
7
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
8
16 0,
9
auto;
10
11
color: transparent;
12
margin-top: 200px;
13
aspect-ratio: 1;
14
}
15
16
.wrapper {
17
padding: 0px 100px;
18
}
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.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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display: inline-block;
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animation-iteration-count: infinite;
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animation-duration: var(--duration-s);
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animation-direction: alternate;
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animation-name: greeting-1-move, greeting-1-squash;
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animation-timing-function: steps(var(--steps, 3), jump-both);
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animation-composition: accumulate;
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will-change: transform;
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}
28 collapsed lines
34
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@keyframes greeting-1-move {
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0% {
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transform: translateY(0px);
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}
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100% {
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transform: translateY(-200px);
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}
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}
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@keyframes greeting-1-squash {
46
0% {
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transform: scaleY(0.5) scaleX(1.5);
48
}
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20% {
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transform: scaleY(1.5) scaleX(0.5);
52
}
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95% {
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transform: scaleY(1) scaleX(1);
56
}
57
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100% {
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transform: scaleY(1) scaleX(1);
60
}
61
}

7. Secondary Action ๐Ÿ”‚

Additional actions that enhance an action

web-animations/principles-7.css
21 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
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cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.greeting {
14
--duration-s: calc(var(--duration, 1) * 1s);
15
}
16
17
.hand {
18
display: inline-block;
19
transform-origin: bottom right;
20
}
21
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.greeting:hover {
23
background-color: var(--color-brand);
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transition: background-color var(--duration-s);
25
}
26
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.hand {
28
animation-delay: calc(0.5 * var(--duration-s));
29
animation-duration: var(--duration-s);
30
}
31
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.greeting:hover .hand {
33
animation-name: hand-wave-multi;
34
}
28 collapsed lines
35
36
@keyframes hand-wave-multi {
37
0% {
38
transform: rotate(0deg);
39
}
40
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15% {
42
scale: 150%;
43
transform: rotate(0deg);
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translate: 0px -8px;
45
}
46
47
50% {
48
scale: 150%;
49
transform: rotate(30deg);
50
translate: 0px -8px;
51
}
52
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85% {
54
scale: 150%;
55
transform: rotate(0deg);
56
translate: 0px -8px;
57
}
58
59
100% {
60
transform: rotate(0deg);
61
}
62
}

8. Exaggeration ๐Ÿ’ฅ

Provide dramatic effect

web-animations/principles-8.css
36 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
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cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.greeting {
14
--duration-s: calc(var(--duration, 1) * 1s);
15
--scale-p: calc(var(--scale, 1) * 1%);
16
}
17
18
.hand {
19
display: inline-block;
20
transform-origin: bottom right;
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}
22
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.greeting:hover {
24
background-color: var(--color-brand);
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transition: background-color var(--duration-s);
26
}
27
28
.hand {
29
animation-delay: calc(0.5 * var(--duration-s));
30
animation-duration: var(--duration-s);
31
}
32
33
.greeting:hover .hand {
34
animation-name: hand-wave-multi;
35
}
36
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@keyframes hand-wave-multi {
38
0% {
39
transform: rotate(0deg);
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}
41
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15% {
43
scale: var(--scale-p);
44
transform: rotate(0deg);
45
translate: 0px -8px;
46
}
47
48
50% {
49
scale: var(--scale-p);
50
transform: rotate(30deg);
51
translate: 0px -8px;
52
}
53
54
85% {
55
scale: var(--scale-p);
56
transform: rotate(0deg);
57
translate: 0px -8px;
58
}
59
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100% {
61
transform: rotate(0deg);
62
}
63
}

9. Staging ๐ŸŽญ

Direct the audience attention

web-animations/principles-9.css
34 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
7
cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.hand {
14
display: inline-block;
15
}
16
17
.greeting {
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--duration-s: calc(var(--duration, 1) * 1s);
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transition-property: all;
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transition-duration: var(--duration-s);
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transition-timing-function: ease-in-out;
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animation-name: greeting-9;
25
animation-duration: var(--duration-s);
26
animation-direction: alternate;
27
animation-iteration-count: infinite;
28
}
29
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.greeting:hover {
31
background-color: var(--color-brand);
32
color: var(--color-on-brand);
33
}
34
35
@keyframes greeting-9 {
36
from {
37
border: solid 4px transparent;
38
}
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to {
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border: solid 4px var(--color-brand);
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}
43
}

10. Straight Ahead & Pose to Pose ๐Ÿ“ผ

Two different techniques for determining frames

  • Straight ahead - Draw frames consecutively
  • Post to Pose - Draw frames at start and end the figure out whatโ€™s in between

11. Solid Drawings ๐Ÿ–ผ๏ธ

Make it feel like 2D shapes occupy a 3D space

web-animations/principles-11.css
29 collapsed lines
1
.greeting {
2
display: inline-block;
3
text-transform: lowercase;
4
padding: 0.5rem 1rem;
5
background-color: var(--color-brand-muted);
6
color: var(--color-on-base);
7
cursor:
8
url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' style='font-size:24px;'><text y='50%'>๐Ÿคš</text></svg>")
9
16 0,
10
auto;
11
}
12
13
.greeting {
14
--duration-s: calc(var(--duration, 1) * 1s);
15
--scale-p: calc(var(--scale, 1) * 1%);
16
--perspective-px: calc(var(--perspective, 1) * 1px);
17
--rotate-x-deg: calc(var(--rotate-x, 1) * 1deg);
18
--rotate-y-deg: calc(var(--rotate-y, 1) * 1deg);
19
--rotate-z-deg: calc(var(--rotate-z, 1) * 1deg);
20
21
margin-top: 20px;
22
transition: all var(--duration-s);
23
}
24
25
.hand {
26
display: inline-block;
27
transform-origin: bottom right;
28
}
29
30
.greeting:hover {
31
background-color: var(--color-brand);
32
transform: perspective(var(--perspective-px)) rotateX(var(--rotate-x-deg))
33
rotateY(var(--rotate-y-deg)) rotateZ(var(--rotate-z-deg));
34
}
37 collapsed lines
35
36
.hand {
37
animation-delay: calc(0.5 * var(--duration-s));
38
animation-duration: var(--duration-s);
39
}
40
41
.greeting:hover .hand {
42
animation-name: hand-wave-multi;
43
}
44
45
@keyframes hand-wave-multi {
46
0% {
47
transform: rotate(0deg);
48
}
49
50
15% {
51
scale: var(--scale-p);
52
transform: rotate(0deg);
53
translate: 0px -8px;
54
}
55
56
50% {
57
scale: var(--scale-p);
58
transform: rotate(30deg);
59
translate: 0px -8px;
60
}
61
62
85% {
63
scale: var(--scale-p);
64
transform: rotate(0deg);
65
translate: 0px -8px;
66
}
67
68
100% {
69
transform: rotate(0deg);
70
}
71
}

12. Appeal ๐ŸŒŸ

  • Simple
  • Clear
  • Compelling

Make the viewer feel something

โช Recap - Principles of Animation

  1. Squash and Stretch
  2. Anticipation
  3. Follow Through and Overlap
  4. Arcs
  5. Slow In & Slow Out
  6. Timing
  7. Secondary Action
  8. Exaggeration
  9. Staging
  10. Straight Ahead & Pose to Pose
  11. Solid Drawings
  12. Appeal

๐ŸชŸ Frameworks and Libraries ๐Ÿ“š

For defining animations, not design systems

When not to use Animations ๐Ÿšซ

  • If the the user has enabled reduced-motion
  • If it will add too much visual noise
  • If they will distract the user
  • Responsiveness and accessibility concerns

Suggestions ๐Ÿ’ก

  • Use animations lightly
  • Less is more, small interactions go a long way
  • Define your identity and use animations to enhance that
  • Understanding interactivity on different screen types
  • Animations should have a purpose

Case Study ๐Ÿ•ต๏ธ

Josh Comeau

  • Changing themes
  • Navigation dropdown
  • Background svg
  • Link hover
  • Twitter link

Lingโ€™s Cars

  • Sense of identity
  • Maximalism can work too

References and Further Reading ๐Ÿ“–

MDN

Principles of Animation

StackOverflow