The HTML open attribute define the details HTML element content should be visible(open) in an HTML document.
Syntax
Following is the syntax −
<details open></details>
Let us see an example of HTML open Attribute −
Example
<!DOCTYPE html> <html> <style> body { color: #000; height: 100vh; background-color: #8BC6EC; background-image: linear-gradient(135deg, #8BC6EC 0%, #9599E2 100%); text-align: center; } </style> <body> <h1>HTML low Attribute Demo</h1> <details open> <summary>Hi! I'm a summary element</summary> <p>Hi! I'm a paragraph element with some dummy text</p> </details> </body> </html>