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This is an early unpublished editor's draft; content is incomplete and subject to change.

Layout reflow supported

supplemental

Normative Text

All content fits within 320 CSS pixels in the default orientation of text without requiring scrolling in more than one direction. Sections of content within the page/view that scroll in a different direction to the page/view fit within 320 CSS pixels of the page-scrolling direction.

Except when

  • 2D relationships. For example, tables, electronic program guides.
  • Canvases of presentational content. For example, slides.
  • Multiple palettes or panels that act on content. For example, Photoshop, IDE.

All block-level elements fit within a 320px inline-size without requiring scrolling in more than one direction.

Tests

This section is non-normative.

Procedure

  1. Set the viewport at 320px in the direction of text.
  2. Check that each section of content fits within 320 CSS pixels.

Expected results

  • #2 is true.

Tests

This content needs to be written.

Key Terms

actively available

available for the user to perceive and use

conformance scope

A set of Views and/or Pages selected to be part of a conformance claim. Where a View or Page is part of a Process, all the Views or Pages in the process must be included.

How a person or organization selects the set is not defined in WCAG3. There maybe informative guidance on selecting a suitable set in future (similar to WCAG-EM), but regional laws or regulations may provide a methodology.

content

information, sensory experience and interactions conveyed

css pixel

visual angle of about 0.0213 degrees

A CSS pixel is the canonical unit of measure for all lengths and measurements in CSS. This unit is density-independent, and distinct from actual hardware pixels present in a display. User agents and operating systems should ensure that a CSS pixel is set as closely as possible to the CSS Values and Units Module Level 3 reference pixel [css3-values], which takes into account the physical dimensions of the display and the assumed viewing distance (factors that cannot be determined by content authors).

page

non-embedded resource obtained from a single URI using HTTP plus any other resources that are used in the rendering or intended to be rendered together

Where a URI is available and represents a unique set of content, that would be the preferred conformance unit.

platform

software, or collection of layers of software, that lies below the subject software and provides services to the subject software and that allows the subject software to be isolated from the hardware, drivers, and other software below

Platform software both makes it easier for subject software to run on different hardware, and provides the subject software with many services (e.g. functions, utilities, libraries) that make the subject software easier to write, keep updated, and work more uniformly with other subject software.

A particular software component might play the role of a platform in some situations and a client in others. For example a browser is a platform for the content of the page but it also relies on the operating system below it.

The platform is the context in which the conformance scope exists.

process

series of views or pages associated with user actions, where actions required to complete an activity are performed, often in a certain order, regardless of the technologies used or whether it spans different sites or domains

view

content that is actively available in a viewport including that which can be scrolled or panned to, and any additional content that is included by expansion while leaving the rest of the content in the viewport actively available

A modal dialog box would constitute a new view because the other content in the viewport is no longer actively available.

viewport

object in which the platform presents content

The author has no control of the viewport and almost always has no idea what is presented in a viewport (e.g. what is on screen) because it is provided by the platform. On browsers the hardware platform is isolated from the content.

Content can be presented through one or more viewports. Viewports include windows, frames, loudspeakers, and virtual magnifying glasses. A viewport may contain another viewport. For example, nested frames. Interface components created by the user agent such as prompts, menus, and alerts are not viewports.