關於「CSS invalid」標籤，搜尋引擎有相關的訊息討論：

invalid - CSS: Cascading Style Sheets - MDN Web Docsdeveloper.mozilla.org › References › CSSCSS Invalid Property Value - Stack Overflowstackoverflow.com › questions › css-invalid-property-valueCSS :invalid & :valid pseudo selector - LinkedInwww.linkedin.com › pulse › css-in