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The @font-feature-values CSS at-rule lets you use a common name in the font-variant-alternates property for features activated differently in OpenType. This can help simplify your CSS when using multiple fonts.

/* At-rule for "nice-style" in Font One */
@font-feature-values Font One {
  @styleset {
    nice-style: 12;
  }
}

/* At-rule for "nice-style" in Font Two */
@font-feature-values Font Two {
  @styleset {
    nice-style: 4;
  }
} 

…

/* Apply the at-rules with a single declaration */
.nice-look {
  font-variant-alternates: styleset(nice-style);
}

The @font-feature-values at-rule may be used either at the top level of your CSS or inside any CSS conditional-group at-rule.

Syntax

Feature value blocks

@swash
Specifies a feature name that will work with the swash() functional notation of font-variant-alternates. A swash feature value definition allows only one value: ident1: 2 is valid when ident2: 2 4 isn't.
@annotation
Specifies a feature name that will work with the annotation() functional notation of font-variant-alternates. An annotation feature value definition allows only one value: ident1: 2 is valid when ident2: 2 4 isn't.
@ornaments
Specifies a feature name that will work with the ornaments() functional notation of font-variant-alternates. An ornaments feature value definition allows only one value: ident1: 2 is valid when ident2: 2 4 isn't.
@stylistic
Specifies a feature name that will work with the stylistic() functional notation of font-variant-alternates. A stylistice feature value definition allows only one value: ident1: 2 is valid when ident2: 2 4 isn't.
@styleset
Specifies a feature name that will work with the styleset() functional notation of font-variant-alternates. A stylset feature value definition allows and illimited amount of values: ident1: 2 4 12 1maps to the OpenType values ss02, ss04, ss12, ss01. Note that values higher than 99 are valid, but doesn't map to any OpenType values and are ignored.
@character-variant
Specifies a feature name that will work with the character-variant() functional notation of font-variant-alternates. A character-variant feature value definition allows one or two values: ident1: 2  maps to cv02=1 and ident2: 2 4 maps to cv02)4 and ident2: 2 4 5 isn't valid.

Formal syntax

@font-feature-values <family-name># {
  <feature-value-block-list>
}

where
<family-name> = <string> | <custom-ident>+
<feature-value-block-list> = <feature-value-block>+

where
<feature-value-block> = <feature-type> { <feature-value-declaration-list> }

where
<feature-type> = @stylistic | @historical-forms | @styleset | @character-variant | @swash | @ornaments | @annotation
<feature-value-declaration-list> = <feature-value-declaration>

where
<feature-value-declaration> = <custom-ident>: <integer>+;

Specifications

Specification Status Comment
CSS Fonts Module Level 3
The definition of '@font-feature-values' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support ? 34 (34) [1] ? ? ?
Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support ? 34.0 (34) [1] ? ? ?

[1] Experimental implementation of the CSS Fonts Level 3 extensions was available since Gecko 24. It was governed by the preference layout.css.font-features.enabled defaulting to true on Nightly and Aurora only.

See also

Document Tags and Contributors

 Contributors to this page: mfluehr, Sebastianz, Moyogo, fscholz, jwhitlock, jsx, HTMLValidator, teoli
 Last updated by: mfluehr,