When you entered <code><h2 style="color: red;">CatPhotoApp</h2></code>, you were styling that individual <code>h2</code> element with <code>inline CSS</code>, which stands for <code>Cascading Style Sheets</code>.
Inside that style block, you can create a <code>CSS selector</code> for all <code>h2</code> elements. For example, if you wanted all <code>h2</code> elements to be red, you would add a style rule that looks like this:
Note that it's important to have both opening and closing curly braces (<code>{</code> and <code>}</code>) around each element's style rule(s). You also need to make sure that your element's style definition is between the opening and closing style tags. Finally, be sure to add a semicolon to the end of each of your element's style rules.
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## Instructions
<sectionid='instructions'>
Delete your <code>h2</code> element's style attribute, and instead create a CSS <code>style</code> block. Add the necessary CSS to turn all <code>h2</code> elements blue.
testString: assert(code.match(/h2\s*\{\s*color\s*:.*;\s*\}/g), 'Ensure that your stylesheet <code>h2</code> declaration is valid with a semicolon and closing brace.');
testString: assert(code.match(/<\/style>/g) && code.match(/<\/style>/g).length === (code.match(/<style((\s)*((type|media|scoped|title|disabled)="[^"]*")?(\s)*)*>/g) || []).length, 'Make sure all your <code>style</code> elements are valid and have a closing tag.');