Updated Code with Music Animation

To add a music animation effect to your custom MP3 player, we can incorporate visual elements that react to the music. A popular choice is to create a "pulse" effect or animated bars that move in sync with the beat or audio amplitude. We can achieve this by using the Web Audio API to analyze the audio data and animate the visual elements based on the audio’s frequency or volume.

Here is how you can add a basic music visualization animation (animated bars) to the MP3 player.