ruby-position

The ruby-position CSS property defines the position of a ruby element relatives to its base element. It can be positioned over the element (over), under it (under), or between the characters on their right side (inter-character).

Try it

Syntax

/* Keyword values */
ruby-position: over;
ruby-position: under;
ruby-position: inter-character;
ruby-position: alternate;

/* Global values */
ruby-position: inherit;
ruby-position: initial;
ruby-position: revert;
ruby-position: revert-layer;
ruby-position: unset;

Values

over: Is a keyword indicating that the ruby has to be placed over the main text for horizontal scripts and right to it for vertical scripts.
under: Is a keyword indicating that the ruby has to be placed under the main text for horizontal scripts and left to it for vertical scripts.
inter-character: Is a keyword indicating that the ruby has to be placed between the different characters.
alternate: Is a keyword indicating that the ruby alternates between over and under, when there are multiple levels of annotation.

Formal definition

Initial value	`alternate`
Applies to	ruby annotations containers
Inherited	yes
Computed value	as specified
Animation type	discrete

Formal syntax

ruby-position = 
  [ alternate || [ over | under ] ]  |
  inter-character

Examples

Ruby positioned over the text

HTML

<ruby>
  <rb>超電磁砲</rb>
  <rp>（</rp><rt>レールガン</rt><rp>）</rp>
</ruby>

CSS

ruby {
    ruby-position:over;
}

Result

Ruby positioned under the text

HTML

<ruby>
  <rb>超電磁砲</rb>
  <rp>（</rp><rt>レールガン</rt><rp>）</rp>
</ruby>

CSS

ruby {
    ruby-position:under;
}

Result

Ruby alternate

HTML

<ruby>
  <rb>A<rb>B<rb>C</rb>
  <rtc>Above</rtc>
  <rtc>Below</rtc>
</ruby>

CSS

ruby {
    ruby-position: alternate; /* this is also the initial value */
}

Result

Specifications

Specification
CSS Ruby Annotation Layout Module Level 1 # rubypos

Specification

CSS Ruby Annotation Layout Module Level 1
# rubypos

Browser compatibility

	Desktop	Mobile
`ruby-position`	84 1 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	84 79 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`). 12-79	38	No Internet Explorer 9 and later support an old draft values: `inline` (equivalent of having `display: inline` on the ruby), and `above` (synonym of the modern `over`).	70 15 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	7 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	84 4.4 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	84 18 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	38	60 14 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	7 Implemented as a non-standard, prefixed, version of `ruby-position`, `-webkit-ruby-position`: it has two properties: `before` and `after` (both equivalent, for ltr and rtl scripts to the standard `over` value used with `ruby-align: start`).	14.0
`alternate`	No See bug 1191394.	No See bug 1191394.	88	No	No See bug 1191394.	No	No See bug 1191394.	No See bug 1191394.	88	No See bug 1191394.	No	No See bug 1191394.
`inter-character`	No See bug 1258284.	No See bug 1258284.	No See bug 1055672.	No	No See bug 1258284.	No	No See bug 1258284.	No See bug 1258284.	No See bug 1055672.	No See bug 1258284.	No	No See bug 1258284.

Desktop

Mobile

Chrome

Edge

Firefox

Internet Explorer

Opera

Safari

WebView Android

Chrome Android

Firefox for Android

Opera Android

Safari on IOS

Samsung Internet

ruby-position

Implemented as a non-standard, prefixed, version of ruby-position, -webkit-ruby-position: it has two properties: before and after (both equivalent, for ltr and rtl scripts to the standard over value used with ruby-align: start).

12-79

Internet Explorer 9 and later support an old draft values: inline (equivalent of having display: inline on the ruby), and above (synonym of the modern over).