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Pure CSS Tab Panel

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Strong

Represents strong importance for its contents. Indicate relative importance by nesting strong elements; each strong element increases the importance of its contents. Changing the importance of a piece of text with the strong element does not change the meaning of the sentence.

Source: html5doctor for Strong

Section

Represents a generic document or application section. In this context, a section is a thematic grouping of content, typically with a header, possibly with a footer. Examples include chapters in a book, the various tabbed pages in a tabbed dialog box, or the numbered sections of a thesis. A web site's home page could be split into sections for an introduction, news items, contact information.

Source: html5doctor for Section

Source

The source element allows authors to specify multiple alternative media resources for media elements. It does not represent anything on its own. The src attribute gives the address of the media resource. The value must be a valid non-empty URL potentially surrounded by spaces. This attribute must be present.

Source: html5doctor for Source

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