Accessible Fixed-Layout ebooks with Circular Software

Follow these steps to create WCAG 'A' accessible fixed-layout EPUB3 directly from InDesign with Circular Software.

Introduction.

Adobe InDesign fails to create EPUBs to the standards required for modern accessible publishing.

Whilst Adobe InDesign can export to Fixed-Layout EPUB, the open standard for accessible digital publications, by using InDesign alone, publishers are left with errors and a lack of accessibility.

Exporting WCAG 'A' accessible Fixed-Layout EPUB3 directly from InDesign and with no coding is possible when using Circular Software. Read more about this topic here No-Code Accessibility for InDesign.

Whilst not all Fixed-Layout EPUBs will require all these steps, we do recommend following them, in this order, for the best results. Especially for your first few publications.

The steps to follow are listed below. Let's get started!

Circular Software also provides a suite of tools to determine and apply reading order and region navigation to complex layouts (e.g. comic books). See the associated tutorial Establishing reading order for complex illustrated ebooks to more info on these aspects of the workflow.

Step 1.

‍add Sections & landmarks.

A reader being able to know their current location in an EPUB and to be able to effectively navigate an ebook is a large part of accessibility.
Section labels are added into the EPUB page code to identify the kind of content that is on the page and major sections become landmarks to help with the navigation of EPUB. e.g. the cover, table of contents, and the start of the main body matter.

The Accessibility Tools panel in CircularFLO or GreenLight has a Section Labels section. Use the Section label tools to mark the starting pages

The Auto add section label to pages tool looks at the paragraph style applied to the first item on the page and if a match is found for an available label. After using the Auto add section label to pages tool, manually check locations of Section labels and remove any duplicates.

Section markers are added as text frames on the pasteboard on the non-printing FLO_INFO layer.

Remove a section marker by deleting the text frame object in InDesign.

Step 2.

‍add Table of Contents.

Longer Fixed-Layout EPUBs should benefit from an internal table of contents within the EPUB code which helps with navigation.
Printed contents pages are often added as text rather than by using the InDesign table of contents feature, which makes them inaccessible.

Although InDesign has a table of contents feature, it is not always used. Circular Software tools have the ability to add an accessible table of contents to any fixed-layout EPUB.

Also, tappable hyperlink regions can be added to any part of the page which then act as cross references.

Step 3.

‍add Reading Order.

As soon as there is more then one object on a page then the order in which that content is to be read becomes important
For good accessibility we need assume that the visual cues offered by text size and formatting are not enough and so we add the reading order

When faced with a well designed but complex spread an experienced, sighted reader will quickly make subconscious decisions on the hierarchy and reading order.

Unfortunately, the reading order of an InDesign page bears no relation to the position of the objects on the page or the styling used, but instead is presented in a reverse stacking order. It is not easy to understand the reading order or to influence it without affecting the design.

Circular Software reading order tools give us a way to add reading order by selecting objects in sequence or drawing regions over the page.

Along with text frames, images and their captions, regions and full page artwork are also added into the reading order.

The applied reading order is shown with overlaid non-printing visual markers on the page which can be shared with others for approval.

Once added reading order can be modified.

In some cases we may want to text to appear on the page but not be added to the reading order. e.g. a running head or page number.

For more complex layouts, e.g. comic books, an additional tutorial Establishing reading order for complex illustrated ebooks is also available

Step 4.

Heading hierarchy.

The use of heading tags ensures users do not have to rely on visual styling to understand and navigate the document
Heading levels are applied to text by the use of InDesign paragraph styles

For the best accessibility headings should be applied using Heading tags. Also the order of the headings should be logical. A H1 tag is the top level with a secondary level of heading, an H2 following an H1.

Heading tags apply structure to content and can be used for navigation so should be applied in order. e.g. it is not correct practice to follow an H1 tag with an H3 tag. More info on heading hierarchy on the DAISY Accessible Publishing Knowledge Base.

Heading levels are applied by the use of InDesign paragraph styles and InDesign has a useful feature to view and edit all export tags in one dialog (InDesign Paragraph Styles Panel options > Edit All Export Tags…) More info Edit All Export Tags on EPUB Secrets.

Whilst InDesign doesn't actually apply these heading tags to fixed-layout EPUB… Circular Software does and also has tools and checks to ensure headings are correctly applied.

Step 5.

‍Image descriptions.

Adding descriptions to images and regions is an important way to add their meaning to those who may not be able to view them
Background images, decorative images and images that are fully described by on page captions should be marked as such

Rather than placing alt text descriptions into image metadata, the best descriptions take the context of the image or region on the page along with the intended audience into consideration.

Circular Software tools allow the addition and editing of descriptions to images and regions directly on the InDesign page, which are able to be shared with others, then apply the descriptions in the final output.

Circular Software tools connect with SIDD (Simple Image Descriptions Database) to connect people, documents and images to a lightweight but powerful and centralized source for contextual image descriptions.

What is SIDD?

SIDD connects people, documents and images to a lightweight but powerful and centralized source for contextual image descriptions. Using the power of the web, SIDD brings structure and consistency to our image description workflows, creating a centralized repository for all of your accessible descriptions.

What are Image Descriptions?

Alt Text: A brief textual description of the purpose and meaning of an image that lives within the HTML <alt> attribute. Alt text helps people using assistive technologies like screen readers quickly understand the most important and relevant details about the image.
Extended Description (aka Long Description): A detailed textual description that continues the information provided in the alt text. An extended description is not required if alt text provides a sufficient text alternative to the image.

How does SIDD work?

Don't let that word database in SIDD (The Simple Image Descriptions Database) scare you!

By using Airtable (think of Airtable as Google docs x 100) we have an extremely easy to use, flexible and responsive online tool which can be linked to the images in your publications.

The SIDD description editor

SIDD comes with a ready made SIDD description editor. With this we have use a clean, easy to use, shareable online editor for viewing, adding and editing image descriptions.

As image descriptions are added using the SIDD description editor they are added to the SIDD database ready to be easily extracted or exported.

Do we have to change our workflow?

SIDD takes a lightweight approach and, by dealing purely with previews and information about your images and not the actual images themselves, it does not impose any changes to your workflow.

There is no need to move or rename any files, no need for large file transfers and no need to change your publishing workflow when using SIDD, unless you want to!

Is it secure?

Yes. Because SIDD is built using Airtable, which has the ability to add ownership and access levels, your information remains backed up and secure.

How much does SIDD cost?

The short answer is NOTHING! An Airtable account can be created free of charge and SIDD can be used on a free plan for up to 1000 current images by up to five collaborators in your workflow.

The SIDD template has been made freely available on Airtable for anyone to use.

Sounds great, how do I get started?

Start Simple

Once you have registered for Airtable and copied the free SIDD template, you have access to a simple structured base to add and share image descriptions.

You can also import Google Sheets, Excel docs or many other apps using a CSV file. SIDD data can also be exported out to CSV or even printed out if you really need to!

Get More Powerful

Using software tools to automate and integrate your documents and images with your SIDD makes it possible to prepare images for description in bulk and at speed.

textBOX use SIDD to organise and share professional image descriptions, created by humans, with their publishing clients.
Circular Software tools rapidly feed and retrieve previews and data with SIDD and automatically apply professional image descriptions within Adobe InDesign.

Want to support us or add to SIDD?

We want SIDD - The Simple Image Descriptions Database - to become a well known and widely used shared resource for image descriptions.

The best way to support SIDD is to use it, to share your experiences with us and share this information with others.

Ready to get started?

Follow the steps in our SIDD (Simple Image Descriotions) Setup article to get set up with Airtable, SIDD templatesand to start using SIODD with Circular Software.

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Step 6.

‍Check Text contrast.

Insufficient contrast between text and background colours can affect everyone but contrast is of greater importance for those with sight difficulties.
A Circular Software tool takes the colours from selected InDesign objects and reports their contrast ratios.

For print work, a text size above 18pt means a lower contrast ratio can be used but for fixed-layout ebooks, although text maybe larger in print, a smaller screen size may affect the actual size.

More info and help is available at the WebAIM Contrast Checker page.

Step 7.

‍Add Accessibility metadata.

By declaring just how accessible (or not!) an EPUB file is, we can inform the retailer and reader about the features that the ebook has before purchase or download
Adding accessibility metadata is now a requirement for accessible EPUB

Structured information about the EPUB content lets everyone know the accessibility features and potential hazards. Including this metadata is now part of the latest EPUB standards and will be flagged by Ace by DAISY see the tutorial step 11. Validation & testing below.

InDesign has a way to add this Accessibility metadata but Circular Software users can more easily add it by using a CircularFLO Metadata panel and synchronising between documents with the Metadata Matcher tool.

The addition of extra metadata is recommended to help with discovery and accessibility.

Accessibility Metadata is an important requirement for accessible EPUBs which describes the accessibility features of the EPUB.

Ebook distributors, platforms and retailers rely on this industry standard information to help readers, librarians and educators make informed choices on which ebooks they can offer to readers.

With the free Metadata Matcher tool in GreenLight this accessibility metadata can be easily viewed, edited, applied, extracted and copied between documents.

To add a CircularFLO Metadata Panel go to the CircularFLO Accessibility Tools menu > Accessibility Tools > Add Metadata panel

Definition of Accessibility Features

Content features of the resource, such as accessible media, supported enhancements for accessibility and alternatives.

The None value is only to be used to indicate that all other values in this section are set to no. As all InDesign documents have page markers added this can left set to no. A double negative meaning it is not none!

The Alternative Text value is used to indicate that all images and other non-text content (e.g., audio and video) that is relevant to understanding a publication includes a text alternative.

The ARIA value is used to indicate that the ARIA roles are used. This is true when exporting with CircularFLO.

The Audio Description value is used to indicate that description tracks are included for any video sources that require them.

The Display Transformability property is used to indicate that a publication does not restrict the ability of users to modify the display of textual content (e.g., to change the font family, font size, line height and word spacing).

The High Contrast Display value is used to indicate that there is at least a 7:1 contrast ratio between the foreground text and the background, including for images of text.

The Index value is used to indicate that a publication contains one or more indexes of the content (e.g. a topical index or index of names).

The Latex value is used to indicate that a publication contains math equations formatted using the LaTeX typesetting system.

The Long Description value is used to indicate that all complex content (images, tables, charts, equations, etc.) include an extended description of their purpose.

The MathML value is used to indicate that the MathML markup language has been used to encode the mathematical equations.

The Open Captions value indicates that a publication includes open captions for auditory content. Open captions are burned directly into the video and are always visible in an unchangeable form.

Both Page Break Markers the Page Navigation and values are used to indicate that static print page break locations are included in the ebook text. This is true for CircularFLO exported Fixed-lyout EPUBs.

The Reading Order value is used to indicate that there is a logical reading order to the text of a publication.

The Ruby Annotations value is used to indicate that a publication comes with explanatory annotations that improve the accessibility of the work.

The Structural Navigation value is used to indicate that all headings are properly marked up.

The Synchronized Audio Text value is used to indicate that synchronized playback of prerecorded audio with text highlighting is available.

The Table Of Contents value is used to indicate that a publication includes a table of contents for navigating the major sections of the work.

The

The Unlocked value is used to indicate that no digital rights management (DRM) or other content restriction protocols are applied to the content.

Definition of Access Modes

An access mode through which the intellectual content of a described resource or adaptation is communicated.

The auditory value is used to indicate that there is an auditory component to the content (e.g., audio tracks on their own or as part of a video, or an audiobook).

The tactile value is used to indicate that a publication contains tactile content, such as braille-formatted text or tactile images.. This is commonly left set to no here.

The textual value is a common one as it is used to indicate that a publication contains text content.

The visual value is used to indicate that a publication contains visual content such as images, grapics and video.

Definition of Access Mode Sufficient

A list of single or combined access modes that are sufficient to understand all the intellectual content of a resource.

The property takes one or more of the following values:

auditory
tactile
textual
visual

The meaning of these values is the same as their definitions for access modes, but sufficient access modes identify the different combinations of senses that can be used to sufficiently consume the content, not just the raw access modes of the content itself.

A publication with images and text, for example, will require both visual and textual modes to be consumed. If the images are also adequately described (alt text and extended descriptions, as appropriate) a single textual mode would also be sufficient, indicating someone who is blind can consume the content.

Definition of Accessibility Hazards

A characteristic of the described resource that is physiologically dangerous to some users.

The flashing values is used to indicate that there is content in the publication that flashes more than three times a second.

The motionSimulation value is used to indicate that there is content that simulates motion.

The sound value is used to indicate that a publication contains any auditory content.

The none value is used when the publisher is sure that the content presents no known hazards for users.

The unknown value is used to indicate that a publisher has not yet checked their publication for hazards or is unsure whether some content might present a hazard.

These descriptions have been generously supplied by DAISY. For Pro users a full description of all these accessibility categories can be found on the DAISY article on Schema.org Accessibility Metadata.

Our free tool allows InDesign users to easily view, edit, apply, extract and copy accessibility metadata.

Accessibility Metadata is an important requirement for accessible EPUBs which describes the accessibility features of the EPUB.

Ebook distributors, platforms and retailers rely on this information to help readers, librarians and educators make informed choices on which ebooks they can offer to readers.

The Metadata Matcher tool affects InDesign's fixed layout EPUB export options to help CircularFLO users. Hold down the option key when clicking the tool to apply to reflowable EPUB export settings.

InDesign can include accessibility metadata with EPUB exports. CircularFLO also uses this same information.

But… this complex set of metadata options needs to be manually applied in every file and can only be added at the time of export in an easily missed tab.

With the free Metadata Matcher tool in GreenLight this accessibility metadata can be easily viewed, edited, applied, extracted and copied between documents.

The Metadata Matcher tool is available from GreenLight Tools menu > Accessibility Tools > Metadata > Metadata Matcher and expects a CircularFLO Metadata panel to be present on the active document's pasteboard.

The CircularFLO Metadata panel is an InDesign table containing all the industry standard metadata for declaring accessibility. Find out more in our article Accessibility metadata.

If not already present a new CircularFLO Metadata panel can be added from the GreenLight Tools menu > Accessibility Tools > Metadata > Add CircularFLO Metadata panel

The CircularFLO Metadata panel shows the metadata applied to the document

The CircularFLO Metadata panel can be edited using InDesign's Type Tool.

Declare which accessibility features are present in the document by changing a row value from no to yes.

The metadata settings can either be pulled from the active InDesign document to the panel, or pushed from the panel to the export settings of the InDesign document, to synchronise them.

The panel rows will change from grey to black when metadata has been synchronised by running the Metadata Matcher tool.

Click the Metadata Matcher tool to check whether the metadata is synchronised. If so, a dialog confirms this.

Dialog confirming the Accessibility Metadata is synchronised

If a change is present then the dialog offers a choice, to match the InDesign document's export settings to the panel, or vice versa.

A dialog offers the choice to how to match the accessibility metadata

Matching metadata across documents

To apply the metadata from one document to another:

Copy an existing CircularFLO Metadata panel between documents using InDesign Edit menu > Copy and InDesign Edit menu > Paste In Place‍
Click the Metadata Matcher tool
In the dialog shown choose Match document to panel

Step 8.

Add preferences panel

The CircularFLO Preferences Panel adds custom instructions that control the export of your document
Options include settings for graphics, reading order, language, read aloud and text

With no CircularFLO Preferences Panel added the default values will be used.

CircularFLO will run successfully without a Preferences panel added but, to be in control and alter many of the default settings for your ebooks it may be useful to add one.

Open article page

CircularFLO will run successfully without a Preferences panel added but, to be in control and alter many of the default settings for your ebooks it is recommended to add one.

To add a Preferences Panel, choose the Add Preferences Panel button in the CircularFLO Document Tools panel.

The CircularFLO Preferences panel is an InDesign table placed in the pasteboard to the right of the current spread. It can be moved to anywhere in the document, but we recommend placing on the first spread of the first document in your publication.

Sections and headings are shown on the left. Default values are shown in the right column and can be altered to suit your needs.

Lots of options make the panel quite large! It will split to multi columns if there is not enough space for in the document. Unneeded rows may be deleted and the default values will still apply.

The panel is laid out in the following sections.

Output options

Export Amazon ready file: CircularFLO can output ebooks to EPUB3 and Amazon ready files to upload to Amazon KDP. The default here is no, change to yes to include Amazon files in your output.

Export MasterPlan package: The default is no, change to yes to prepare EPUBs and associated files ready for uploading to MasterPlan from Circular Software, a sister product to securely search and share publications online.

Validate with EPUB-Checker: Passes the exported EPUB to Pagina EPUB-Checker for validation. The default is yes, change to no to not automatically check for EPUB validation.
Note: that Pagina EPUB-Checker needs an update for this feature to work on macOS Mojave and later.

Check accessibility with ACE: Passes the exported EPUB to ACE BY DAISY for accessibility checking. The default is no, change to yes to automatically check for EPUB Accessibility on export.

Cover image options

Use first page as cover: To indicate whether the first page should be also used to generate the cover image of the eBook. The default is no, changing to yes will mean the dialog to choose a cover is not shown when making your ebook.

JPEG export options

JPEG quality: The quality setting used for background images can be chosen here by entering either low, medium, high or maximum. Remove the words to leave the preferred value. The default setting is high quality and this is recommended unless your file sizes become too large.

Megapixels per page: The total number of megapixels per page background (1 megapixel = 1 million pixels). A higher number gives more potential quality for fine zoomed-in detail but also means larger file sizes. The default of 3.2 is recommended for books up to one hundred pages. Maximum value is 4.

Export RGB images: By default all background pages use RGB JPEG graphics. The default is yes, changing to no for mono books to reduce file sizes by using greyscale graphics. This setting does not affect the cover, only all inside pages.

Simulate overprinting: When working with existing print files or PDFs it may be necessary to simulate the overprint settings used in order to get the same visual effects in your eBook. Default is yes, Pro users may change this value to no if necessary.

Fixed Layout Reading options

Lock Orientation: By default the EPUB document can alter how it is displayed, in most Ebook readers, according to the device orientation (which way round the reader is holding a tablet or phone). The default is no, change to yes to force an ebook to be fixed in either portrait or landscape mode.

Add Region-Based Navigation: The default is no. Switch to yes to add an extra file into the valid fixed layout EPUB output that contains the positions and reading order for region-based navigation. This method require a modern EPUB reader that supports region-based navigation.

Left to right page progression: The standard setting for western books is to read from left to right. The default is yes, changing to no to present the pages to the reader in a right to left reading order. Suitable for Arabic, Persian, Urdu, Hebrew, Yiddish.

View double page spreads as double page spreads: Many illustrated books make use of being viewed as 'double page spreads', the left and right pages shown together, as part of their design. This can also be true for ebooks. The default is yes, change to no to split any facing pages in InDesign into single pages in the ebook.

Read Aloud options

Read aloud audio track to use for the document: If choosing to use a single audio track for the entire read aloud ebook then the path to the audio track is shown here. This value is not hand entered but instead is set when using the CircularFLO Read Aloud Tools.

Read aloud highlights added as background colour: When highlighting text or images along with an audio track, there is a choice whether to alter the colour of the text or image itself, or whether to add a background colour. The default is yes, changing to no means read aloud highlights are not applied as a background colour.

Read aloud highlight colours: The colours used for read aloud highlighting can be consistently applied or quickly altered across the whole document by amending these applied colours, using the InDesign swatches panel.

Text and font options

Main Language: The language used for the ebook is declared within the ebook itself. This language is detected from the InDesign file but can be altered here. A tool to only offer valid options is coming soon… but until then it is advised to pick a value from the official ISO Language list.

Prefer InDesign live text: Use InDesign's method of exporting text. This is recommended for accuracy and accessibility (once exported with CircularFLO!) The default is yes, change to no to embed any text which is not on the FLO_LIVE_TEXT layer.

Export InDesign CSS: The styling of live text used on the ebook page is written as CSS (Cascading Style Sheets) in the ebook's internal code. The default is yes, the option to change to no is included for experienced users who may find it useful to not included InDesign's own CSS when adding alternative CSS files.

Add external CSS: Experienced users may find it useful to add alternative CSS files instead of or in addition to the styles exported from InDesign. The paths to one or more CSS files to include in the ebook are added using the Add / Relink external CSS tools in the CircularFLO Document Tools panel.

Use Font Obfuscation on FLO_LIVE_TEXT layer: InDesign automatically applies 'font obfuscation' to ‘mangle’ the fonts in the ebook so they are no use outside the EPUB package. If using local fonts for text on the CircularFLO live text layer then the font obfuscation can be avoided. The default is no, change to yes to add the entire original font into the EPUB.

Many of the default settings for your ebooks can altered in this one important panel.

Open article page

NB: If using the Region-Based Navigation feature, this preference needs to be set from no to yes in the CircularFLO Preferences panel before export

Step 9.

‍Run GreenLight AccessIBILITy CHEcks.

InDesign file set up and preparation is automatically checked and help given where needed
Spot and fix any issues whilst in InDesign, before exporting to EPUB

GreenLight from Circular Software ensures InDesign files are correct, complete and consistent. GreenLight comes in Custom, Pro and Free versions and we have made GreenLight FREE free of charge to run accessibility checklists. More info here.

With GreenLight installed, select and run the free GreenLight checklist Accessibility Checks - Fixed-Layout EPUB to check the readiness of the InDesign file or book. Checks include:

Fonts
Links
Styles
Metadata
Structure
Image descriptions

Step 10.

‍Export with CircularFLO.

All the file preparation from the previous steps using Circular Software tools and checks is now applied by exporting with CircularFLO
For ebooks distributed through Amazon, CircularFLO can also create suitable Fixed-Layout EPUBs that will be converted to Amazon Fixed-Layout ebooks

Most ebook retailers and reading systems support the Fixed-Layout EPUB format for beautifully designed and more sophisticated layouts. This is the open standard for fixed-layout ebooks and contains extensive support for custom fonts, audio, video, interactivity, read aloud media overlays, region navigation, hyperlinks, document structure and more.

The accessibility added in this tutorial also relies on the Fixed-Layout EPUB format.

To generate an accessible Fixed-Layout EPUB:

Choose (CircularFLO Tools menu > CircularFLO Main Panel)‍
Ensuring only the document to be exported is open, click the Create Fixed-Layout EPUB / Amazon file button

The InDesign file or book is processed according to the Preferences
The resulting Fixed-Layout EPUB is saved to a folder on the Desktop

Depending on the preferences selected in step 8 the validation process then starts automatically, as covered in the next step

Fixed-Layout ebooks for Amazon

Amazon has very limited support for fixed-layout ebooks and only recognises hyperlinks and table of contents. There is no support for accessibility, audio, video, interactions, images with transparency or live text using custom fonts in an Amazon Fixed-Layout ebooks from InDesign.

The 2025 version of CircularFLO exports Amazon KF8 files which have since been discontinued by Amazon.
These instructions now cover generating a Fixed-Layout EPUB file compatible with Amazon.

These unsupported features are removed from the Amazon export by deleting layers and amending preferences from our fully prepared InDesign files. We therefore recommend working with a copy of the document.

NB: CircularFLO panels need to remain in the Amazon document. Before removing the FLO_INFO layer, CircularFLO panels should be moved to a temporary layer.

To generate a Fixed-Layout EPUB compatible for Amazon:

With InDesign's Selection tool, select the CircularFLO Metadata, CircularFLO Preferences and CircularFLO Table of Contents panels and temporarily move them to the FLO_BASE layer
Select both the TEXT layer and the FLO_BASE layer in the Layers Panel and choose Layers panel menu > Merge Layers
NB: The remaining layer must be named FLO_BASE

Merging TEXT layer and FLO_BASE layers to a FLO_BASE layer in the InDesign Layers panel

Select every layer but the FLO_BASE layer in the Layers Panel and choose Layers panel menu > Delete Layers

Deleting all but the FLO_BASE layer in the InDesign Layers panel

Create a new layer named FLO_INFO with the Layers panel menu > New Layer…
‍With InDesign's Selection tool, select the CircularFLO Metadata, CircularFLO Preferences and CircularFLO Table of Contents panels and move them back to the FLO_INFO layer

The remaining two layers ready for Amazon EPUB export

If using the Region-Based Navigation feature, one preference needs to be reset from yes to no in the CircularFLO Preferences panel for the Amazon export

Changing the Add Region-Based Navigation option from yes to no in the CircularFLO Preferences panel

Now follow To generate an accessible Fixed-Layout EPUB steps above to export the Amazon-ready (but inaccessible!) Fixed-Layout EPUB version as a separate file.

Step 11.

‍Validation & testing.

Automatically run epubcheck on your exports to ensure they are valid EPUB3
Run additional automated accessibility checks

Post export validation with Pagina EPUB-Checker and accessibility checking with ACE, by DAISY can also be set up.

Select the options in the CircularFLO Preferences Panel to run these two automated checks at the end of the export process.

We recommend downloading these tools before your first conversion.