Master-piece.co.jp W3C HTML Markup Validation
HTML markup errors and warnings
(Rescan now...)
Errors:
Using the “meta” element to specify the document-wide default language is obsolete. Consider specifying the language on the root element instead.
Bad value “Content-Script-Type” for attribute “http-equiv” on element “meta”.
Bad value “content-style-type” for attribute “http-equiv” on element “meta”.
Duplicate ID “logo”.
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Warnings:
Consider avoiding viewport values that prevent users from resizing documents.
The first occurrence of ID “logo” was here.
Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
Taiwan TW