Cobalt Support Quick Reference
Stay organized with collections
Save and categorize content based on your preferences.
HTML elements
<a>
<audio>
<body>
<br>
<div>
<head>
<html>
<link>
(with type="text/css"
)
<lottie-player>
<meta>
<script>
<span>
<style>
<title>
<video>
CSS properties
- align-content
- align-items
- align-self
- animation
- background,
background-color,
background-image
- border,
border-top,
border-bottom,
border-left,
border-right
- border-radius
- border-style
- border-width
- box-shadow
- color
- content
- display
- dpi
- flex
- flex-basis
- flex-direction
- flex-flow
- flex-grow
- flex-shrink
- flex-wrap
- font
- @font-face
- font-family
- font-size
- font-style
- font-weight
- justify-content
- line-height
- margin,
margin-top,
margin-bottom,
margin-left,
margin-right
- max-height,
max-width
- @media
- opacity
- order
- overflow
- padding,
padding-top,
padding-bottom,
padding-left,
padding-right
- position
- top,
bottom,
left,
right
- transform
- transform-origin
- transition
- transition-delay
- transition-duration
- transition-property
- transition-timing-function
- text-align
- text-indent
- text-overflow
- text-shadow
- text-transform
- vertical-align
(supported values:
top
, bottom
, middle
, baseline
)
- visibility
- white-space
- z-index
CSS selectors
- Simple selectors:
'*',
type,
.class,
#id,
:empty,
:focus,
:not()
- Pseudo elements:
:before,
:after,
- Combinators:
' ',
'>',
'+',
'~'
- Grouping with ','
JavaScript Web APIs
Protocols
Containers
- FLV
- MKV (for WebM)
- MP4/FMP4
- WAV
- 16-bit stereo PCM audio (for sound effects)
- AAC
- AV1
- AVC (H.264) at 1080p/60fps (Level
4.2)
- Dolby Digital (AC-3)
- Dolby Digital Plus (Enhanced AC-3, or EAC-3)
- HEVC (H.265)
- VP8/Vorbis
- VP9/Opus
Images
- JPEG
- PNG
- WebP (including animated)
Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. For details, see the Google Developers Site Policies. Java is a registered trademark of Oracle and/or its affiliates.
Last updated 2023-12-12 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-12-12 UTC."],[[["\u003cp\u003eThis webpage documents supported HTML elements, CSS properties and selectors, JavaScript Web APIs, protocols and media formats.\u003c/p\u003e\n"],["\u003cp\u003eSupported HTML elements include basic structure tags, media elements, and interactive components like Lottie animations.\u003c/p\u003e\n"],["\u003cp\u003eComprehensive styling is possible with a range of CSS properties covering layout, fonts, colors, and visual effects, along with selectors for targeting elements.\u003c/p\u003e\n"],["\u003cp\u003eJavaScript Web APIs enable interactions with web pages through features like fetching data, manipulating the DOM, handling media, and managing storage.\u003c/p\u003e\n"],["\u003cp\u003eSupported media formats ensure playback of common audio, video, and image formats through various encodings and container types.\u003c/p\u003e\n"]]],["This content outlines a set of web development technologies, including HTML elements like `\u003ca\u003e`, `\u003cvideo\u003e`, and `\u003cdiv\u003e`, and CSS properties such as `display`, `border`, and `flex`. It details CSS selectors for styling and JavaScript Web APIs like `Fetch`, `DOM4`, and `Web Storage API` for dynamic functionality. It lists protocols (HTTPS, QUIC) and media formats (FLV, MP4, JPEG) used for web content. Security standards like \"Content Security Policy Level 2\" are also mentioned.\n"],null,["# Cobalt Support Quick Reference\n\nHTML elements\n-------------\n\n- `\u003ca\u003e`\n- `\u003caudio\u003e`\n- `\u003cbody\u003e`\n- `\u003cbr\u003e`\n- `\u003cdiv\u003e`\n- `\u003chead\u003e`\n- `\u003chtml\u003e`\n- `\u003clink\u003e` (with `type=\"text/css\"`)\n- `\u003clottie-player\u003e`\n- `\u003cmeta\u003e`\n- `\u003cscript\u003e`\n- `\u003cspan\u003e`\n- `\u003cstyle\u003e`\n- `\u003ctitle\u003e`\n- `\u003cvideo\u003e`\n\nCSS properties\n--------------\n\n- [align-content](https://www.w3.org/TR/css-flexbox-1/#propdef-align-content)\n- [align-items](https://www.w3.org/TR/css-flexbox-1/#propdef-align-items)\n- [align-self](https://www.w3.org/TR/css-flexbox-1/#propdef-align-self)\n- [animation](https://www.w3.org/TR/css3-animations/#animation-shorthand-property)\n- [background](https://www.w3.org/TR/css3-background/#the-background), [background-color](https://www.w3.org/TR/css3-background/#the-background-color), [background-image](https://www.w3.org/TR/css3-background/#the-background-image)\n- [border](https://www.w3.org/TR/css3-background/#the-border-shorthands), [border-top](https://www.w3.org/TR/css3-background/#the-border-shorthands), [border-bottom](https://www.w3.org/TR/css3-background/#the-border-shorthands), [border-left](https://www.w3.org/TR/css3-background/#the-border-shorthands), [border-right](https://www.w3.org/TR/css3-background/#the-border-shorthands)\n- [border-radius](https://www.w3.org/TR/css3-background/#the-border-radius)\n- [border-style](https://www.w3.org/TR/css3-background/#the-border-style)\n- [border-width](https://www.w3.org/TR/css3-background/#the-border-width)\n- [box-shadow](https://www.w3.org/TR/css3-background/#the-box-shadow)\n- [color](https://www.w3.org/TR/css3-color/#foreground)\n- [content](https://www.w3.org/TR/CSS21/generate.html#content)\n- [display](https://www.w3.org/TR/CSS21/visuren.html#propdef-display)\n- [dpi](https://www.w3.org/TR/css-values-3/#resolution)\n- [flex](https://www.w3.org/TR/css-flexbox-1/#propdef-flex)\n- [flex-basis](https://www.w3.org/TR/css-flexbox-1/#propdef-flex-basis)\n- [flex-direction](https://www.w3.org/TR/css-flexbox-1/#flex-direction-property)\n- [flex-flow](https://www.w3.org/TR/css-flexbox-1/#flex-flow-property)\n- [flex-grow](https://www.w3.org/TR/css-flexbox-1/#propdef-flex-grow)\n- [flex-shrink](https://www.w3.org/TR/css-flexbox-1/#propdef-flex-shrink)\n- [flex-wrap](https://www.w3.org/TR/css-flexbox-1/#flex-wrap-property)\n- [font](https://www.w3.org/TR/css-fonts-3/#font-prop)\n- [@font-face](https://www.w3.org/TR/css-fonts-3/#font-face-rule)\n- [font-family](https://www.w3.org/TR/css-fonts-3/#propdef-font-family)\n- [font-size](https://www.w3.org/TR/css-fonts-3/#font-size-prop)\n- [font-style](https://www.w3.org/TR/css-fonts-3/#font-style-prop)\n- [font-weight](https://www.w3.org/TR/css-fonts-3/#font-weight-prop)\n- [justify-content](https://www.w3.org/TR/css-flexbox-1/#propdef-justify-content)\n- [line-height](https://www.w3.org/TR/CSS2/visudet.html#propdef-line-height)\n- [margin](https://www.w3.org/TR/CSS21/box.html#margin-properties), [margin-top](https://www.w3.org/TR/CSS21/box.html#margin-properties), [margin-bottom](https://www.w3.org/TR/CSS21/box.html#margin-properties), [margin-left](https://www.w3.org/TR/CSS21/box.html#margin-properties), [margin-right](https://www.w3.org/TR/CSS21/box.html#margin-properties)\n- [max-height](https://www.w3.org/TR/CSS2/visudet.html#min-max-heights), [max-width](https://www.w3.org/TR/CSS2/visudet.html#min-max-widths)\n- [@media](https://www.w3.org/TR/css3-mediaqueries/)\n- [opacity](https://www.w3.org/TR/css3-color/#transparency)\n- [order](https://www.w3.org/TR/css-flexbox-1/#order-property)\n- [overflow](https://www.w3.org/TR/CSS2/visufx.html#overflow)\n- [padding](https://www.w3.org/TR/CSS21/box.html#padding-properties), [padding-top](https://www.w3.org/TR/CSS21/box.html#padding-properties), [padding-bottom](https://www.w3.org/TR/CSS21/box.html#padding-properties), [padding-left](https://www.w3.org/TR/CSS21/box.html#padding-properties), [padding-right](https://www.w3.org/TR/CSS21/box.html#padding-properties)\n- [position](https://www.w3.org/TR/CSS21/visuren.html#propdef-position)\n- [top](https://www.w3.org/TR/CSS21/visuren.html#position-props), [bottom](https://www.w3.org/TR/CSS21/visuren.html#position-props), [left](https://www.w3.org/TR/CSS21/visuren.html#position-props), [right](https://www.w3.org/TR/CSS21/visuren.html#position-props)\n- [transform](https://www.w3.org/TR/css-transforms-1/#transform-property)\n- [transform-origin](https://www.w3.org/TR/css-transforms-1/#propdef-transform-origin)\n- [transition](https://www.w3.org/TR/css3-transitions/#transition-shorthand-property)\n- [transition-delay](https://www.w3.org/TR/css3-transitions/#transition-delay-property)\n- [transition-duration](https://www.w3.org/TR/css3-transitions/#transition-duration-property)\n- [transition-property](https://www.w3.org/TR/css3-transitions/#transition-property-property)\n- [transition-timing-function](https://www.w3.org/TR/css3-transitions/#transition-timing-function-property)\n- [text-align](https://www.w3.org/TR/css-text-3/#text-align)\n- [text-indent](https://www.w3.org/TR/css-text-3/#text-indent-property)\n- [text-overflow](https://www.w3.org/TR/css3-ui/#propdef-text-overflow)\n- [text-shadow](https://www.w3.org/TR/css-text-decor-3/#text-shadow-property)\n- [text-transform](https://www.w3.org/TR/css-text-3/#text-transform-property)\n- [vertical-align](https://www.w3.org/TR/CSS2/visudet.html#propdef-vertical-align) (supported values: `top`, `bottom`, `middle`, `baseline`)\n- [visibility](https://www.w3.org/TR/CSS21/visufx.html#visibility)\n- [white-space](https://www.w3.org/TR/css-text-3/#white-space-property)\n- [z-index](https://www.w3.org/TR/CSS21/visuren.html#propdef-z-index)\n\nCSS selectors\n-------------\n\n- Simple selectors: ['\\*'](https://www.w3.org/TR/selectors4/#universal-selector), [type](https://www.w3.org/TR/selectors4/#type-selectors), [.class](https://www.w3.org/TR/selectors4/#class-html), [#id](https://www.w3.org/TR/selectors4/#id-selectors), [:empty](https://www.w3.org/TR/selectors4/#empty-pseudo), [:focus](https://www.w3.org/TR/selectors4/#focus-pseudo), [:not()](https://www.w3.org/TR/selectors4/#negation-pseudo)\n- Pseudo elements: [:before](https://www.w3.org/TR/selectors4/#pseudo-element), [:after](https://www.w3.org/TR/selectors4/#pseudo-element),\n- Combinators: [' '](https://www.w3.org/TR/selectors4/#descendant-combinators), ['\\\u003e'](https://www.w3.org/TR/selectors4/#child-combinators), ['+'](https://www.w3.org/TR/selectors4/#adjacent-sibling-combinators), ['\\~'](https://www.w3.org/TR/selectors4/#general-sibling-combinators)\n- [Grouping with ','](https://www.w3.org/TR/selectors4/#grouping)\n\nJavaScript Web APIs\n-------------------\n\n- [`Crypto.getRandomValues`](https://www.w3.org/TR/WebCryptoAPI/#crypto-interface)\n- [CSSOM](http://www.w3.org/TR/cssom/) (partial)\n- [CSSOM View](https://www.w3.org/TR/cssom-view-1/) (no scrolling, moving, resizing)\n- `Console.log`\n- [CORS](https://www.w3.org/TR/2020/SPSD-cors-20200602/)\n- [DOM4](http://www.w3.org/TR/dom/) (partial)\n- [EncryptedMedia Extensions v0.1b](https://dvcs.w3.org/hg/html-media/raw-file/eme-v0.1b/encrypted-media/encrypted-media.html) (unprefixed)\n- [Fetch](https://www.w3.org/TR/cors/) (supports text(), JSON(), arrayBuffer(), types)\n- `Image` (for preloading and caching only)\n- [Intersection Observer](https://www.w3.org/TR/intersection-observer/)\n- [Media Session](https://www.w3.org/TR/mediasession/)\n- [Media Source Extensions, Editor's Draft 09 August 2012](https://rawgit.com/w3c/media-source/6747ed7a3206f646963d760100b0f37e2fc7e47e/media-source.html)\n- [Streams API](https://www.w3.org/TR/streams-api/)\n- [SubtleCrypto](https://www.w3.org/TR/WebCryptoAPI/#subtlecrypto-interface)\n- [Typed Arrays](https://www.khronos.org/registry/typedarray/specs/latest/) (partial)\n- [URL](https://url.spec.whatwg.org/#api) (partial)\n- [Web Audio API](https://www.w3.org/TR/webaudio/) (partial)\n- [Web Storage API](https://www.w3.org/TR/webstorage/)\n- [WebIDL Level 2](http://dev.w3.org/2006/webapi/WebIDL/)\n- [WebSocket API](https://www.w3.org/TR/websockets/)\n- [`window.atob()` and `window.btoa()`](https://html.spec.whatwg.org/multipage/webappapis.html#dom-windowbase64-btoa)\n- [XMLHttpRequest Level 1](http://www.w3.org/TR/XMLHttpRequest/)\n\nProtocols\n---------\n\n- https:\n- h5vcc-embedded: (for embedded resources)\n- [Content Security Policy Level 2](https://www.w3.org/TR/CSP2/) in HTTP headers is *required*, and report-only is disabled.\n- QUIC\n- SPDY\n\nMedia formats\n-------------\n\n### Containers\n\n- FLV\n- MKV (for WebM)\n- MP4/FMP4\n- WAV\n\n### Encodings (depending on platform support)\n\n- 16-bit stereo PCM audio (for sound effects)\n- AAC\n- AV1\n- AVC (H.264) at 1080p/60fps ([Level\n 4.2](https://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Levels))\n- Dolby Digital (AC-3)\n- Dolby Digital Plus (Enhanced AC-3, or EAC-3)\n- HEVC (H.265)\n- VP8/Vorbis\n- VP9/Opus\n\n### Images\n\n- JPEG\n- PNG\n- WebP (including animated)"]]