The classic three-line hamburger menu icon animating smoothly into an X when a mobile navigation menu opens is a small but expected interaction detail on almost every responsive site's mobile menu button.
Click the icon to preview the animated transition between the hamburger and X states, customize the line color, then copy the complete HTML and CSS needed to implement the same animated icon in your own navigation menu button.
The animation works by rotating the top and bottom lines 45 degrees in opposite directions while fading out the middle line, all through CSS transitions triggered by toggling a single "active" class on the button element.
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This kind of task shows up constantly in everyday writing, coding, design, and admin work, which is exactly why a dedicated, focused tool saves so much back-and-forth.
Frequently asked questions
Does clicking this actually open a menu, or just animate the icon?
This preview only animates the icon itself; in your own implementation, you'd pair the same class toggle with your actual menu's show/hide logic so the icon state matches whether the menu is open.
Can I adjust how fast the animation transitions?
Yes, adjust the transition-duration value in the generated CSS to make the hamburger-to-X animation faster or slower to match your site's overall interaction feel.