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Reference > CSS parsing issues

Parsing issues independent of CSS specification

Code
Summary
Details
E700
Missing end of comment
A CSS comment was found, but the end of the comment was missing.
E701
The closing quote is missing
An opening quote was found, but the matching end quote was missing. Outside of strings, quotes must always appear in matching pairs, and any single quotes must be escaped using '\'.
E702
Closing brace '}' is missing
The start of a block '{' was found, but the matching end brace '}' was missing.
E703
Mismatched pairs of '()', or '[]' found
Outside of strings, you must have matching pairs of parentheses '()' and square brackets '[]'. This error is normally displayed when there is a missing parenthesis or bracket, or an additional one has been entered by mistake, or an extra one has been deliberately added but hasn't been properly escaped using '\'.
E704
An incomplete at-rule has been detected
The start of an at-rule was found, but the rest of the rule appears to be missing.
E705
A block was expected but was not found
A block was expected, but the opening brace '{' at the start of the block could not be found.
E706
A selector was expected but could not be found
A selector appears to be missing. This may be caused by the complete absence of any selector, or in a complex selector one of the simple selectors is missing. This may be due to a simple error such as having an extra comma.
E707
The block appears to have ended prematurely
The closing brace '}' of a block appears before the end of the declaration.
E708
The property name is missing
A property name was expected but could not be found.
E709
Incomplete declaration
The declaration appears to be incomplete. Either no property name or no values were found.
E710
The semi-colon is missing from the end of the at-rule
at-rules should either have a block or a statement ending with a semi-colon, and neither could be found.
E7111
The identifier includes a character which is not allowed
There are restrictions on what characters are allowed here. See CSS Level 3 ident-token definition.
E7112
The the escape character '\' is not allowed at the end of an identifier
There are restrictions on what characters are allowed here. See CSS Level 3 ident-token definition.
E7113
Two dashes '--' are not allowed here
There are restrictions on what characters are allowed here. See CSS Level 3 ident-token definition.
E7114
A single dash '-' is not allowed at this place
There are restrictions on what characters are allowed here. See CSS Level 3 ident-token definition.
E7115
A dash followed by a number is not allowed here
There are restrictions on what characters are allowed here. See CSS Level 3 ident-token definition.
E7116
The selector cannot consist solely of, or end with, any of the characters: ':#.|'
These characters are special and can only be used in certain places in the selector. See Selectors Grammar.

Reference > CSS non-conformance

Issues due to non-conformance with the chosen CSS specification

Code
Summary
Details
E721
Unrecognised at-rule
The at-rule is not recognised as valid for the selected CSS Level.
E722
The @charset rule is not allowed here
The @charset rule can only be used in a separate CSS document and not in HTML documents.
E723
The @charset rule must be the first line in the document
The exact 10 characters @charset " must be the first thing in the document. Anything, even white space, prior to this will trigger this error. See @charset.
E724
Unrecognised character set
The character set specified is not recognised. This may be because it is misspelt.
E725
The @import rule does not precede all other rules
Any @import rules must precede all other rules, except the @charset rule. See @import.
E726
The at-rule is incorrectly formatted
The at-rule does not follow the standard definition. LINK TO STANDARD.
E727
Invalid URI
It is an invalid URI, most likely containing invalid characters such as spaces. See RFC 3986.
E7281
This item is not allowed here
An at-rule, property or other item was used, which is not allowed in this context. LINK TO STANDARD.
E7282
The at-rule AT_RULE is not allowed here
An at-rule was used, which is not allowed in this context. See the link to the standard for what is allowed. LINK TO STANDARD.
E7283
The property PROPERTY NAME is not allowed here
A property was used, which is not allowed in this context. LINK TO STANDARD.
E7291
Invalid page pseudo-class
The @page rule can only be used with specific pseudo-classes. LINK TO STANDARD.
E7292
Missing page selector
A page selector was expected but appears to be missing. This can be caused by an extra comma in the list of page selectors. LINK TO STANDARD.
E7293
Invalid identifier in page selector
The identifier used in the page selector includes a character which is not allowed. See CSS Level 3 ident-token definition. LINK TO STANDARD.
E730
Missing font family
With the @font-feature-values rule, one or more font family names should be provided.
E731
One or more of the listed font families is badly formatted
One or more of the font family names listed do not meet the requirements of the specification. LINK TO STANDARD.
E732
Missing feature value list
With font variant value definitions, a list of feature values must be provided.
E733
Invalid feature value list
The list of feature values does not meet the requirements of the specification.
E735
The @namespace rule does not precede all other rules
Any @namespace rules must precede all other rules, except the @charset and @import rules. See @namespace.
E736
The namespace NAMESPACE has not been not declared
A @namespace rule declaring the namespace used in the selector was not found.
E737
A counter-style system descriptor is required
The @counter-style at-rule must have a system descriptor. LINK TO STANDARD.
E738
The counter-style name has an invalid name
The @counter-style at-rule cannot have any of these names: disc, decimal, default, unset, inherit, initial, revert or none. LINK TO STANDARD.
E739
The @charset rule is badly-formed
@charset must be written literally; the 10 characters @charset " (lowercase, no backslash escapes), followed by the encoding name, and ending with "; See @charset.
E740
Missing or invalid palette name
With the @font-palette-values at-rule, a valid author-defined palette name must be provided. LINK TO STANDARD.
E741
A font-family descriptor is required
The @font-palette-values at-rule must have a font-family descriptor. LINK TO STANDARD.
E742
Missing or invalid position-try-option
With the @position-try at-rule, a valid position-try-option must be provided. LINK TO STANDARD.
E755
Pseudo-elements can only appear at the end of a selector
Pseudo-elements may only be appended after the last simple selector of the selector. See Pseudo-Elements.
E756
Unrecognised pseudo-element or pseudo-class
Each CSS standard allows different pseudo-elements and pseudo-classes to be used, and one used here does not match the list of allowed pseudo-elements/pseudo-classes for this CSS Level.
E757
A media type is missing
A media type was expected but appears to be missing. This can be caused by an extra comma in a list of media types.
E758
The media type MEDIA TYPE was not recognised
Each CSS Level allows different media types to be used, and the type used here does not match the list of allowed types for this CSS Level. LINK TO STANDARD.
E759
The media query contains a parsing error
The media query could not be parsed properly. This is typically caused by a colon ':', or range character '>', '<', '=' missing or in the wrong place.
E760
Unrecognised media feature: MEDIA FEATURE
The media feature name is not recognised for the selected CSS Level. LINK TO STANDARD.
E761
INVALID MEDIA FEATURE: OFFICIAL RULES
The value used is invalid for this media feature, because the value does not follow the allowed rules for this feature. A list of valid rules will be displayed for the feature.
E762
The to and from keywords must appear only once
The to and from keywords must appear only once in a keyframe selector. See @keyframes.
E763
Invalid percentage found in keyframe selector
Percentages must end with the '%' character and the value must be between 0% and 100%. See @keyframes.
E764
Invalid identifier found in keyframe selector
The identifier used in the keyframe selector includes a character which is not allowed. See CSS Level 3 ident-token definition. LINK TO STANDARD.
E776
Unrecognised property: PROPERTY NAME
The property name is not recognised for the selected CSS Level.
E777
INVALID VALUE: OFFICIAL RULES
Check the value against the list of valid rules from the official standard. LINK TO STANDARD.
E779
The !important keyword is not allowed here
The !important keyword is only allowed in property values and not in declaration values.
W776
A vendor extension has been used
Authors should avoid using vendor extensions where possible. See Vendor-specific extensions.
W777
This item is experimental and has been ignored: ITEM
Because this item is so new, it's definition has not yet been agreed upon, and so it has not been tested. Experimental items should be avoided as few browsers may support them, and their definition may change at any time.
W778
The media type MEDIA TYPE is deprecated
This media type has been deprecated and so should no longer be used. Authors must not use these media types; instead, it is recommended that they select appropriate media features that better represent the aspect of the device that they are attempting to style against. LINK TO STANDARD.
W779
The media feature MEDIA FEATURE is deprecate
This media feature has been deprecated and so should no longer be used. Authors must not use these media features; instead, it is recommended that they select alternative media features as detailed in the link to the specification. LINK TO STANDARD.