How to make animated Accordion with symbols

In this example we have added a "plus" sign to each button. When the user clicks on the button, the "plus" sign is replaced with a "minus" sign.

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i love animated objects and thus i hope to correctly assume that equally you do, on this example the accordion has been animated to slide down using the following code changes to css and js

Sliding accordions

The css


.panel {
    padding: 0 18px;
    background-color: white;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.2s ease-out;
}




The js
var acc = document.getElementsByClassName("accordion");
var i;

for (i = 0; i < acc.length; i++) {
  acc[i].addEventListener("click", function() {
    this.classList.toggle("active");
    var panel = this.nextElementSibling;
    if (panel.style.maxHeight){
      panel.style.maxHeight = null;
    } else {
      panel.style.maxHeight = panel.scrollHeight + "px";
    } 
  });
}

Secondly the "plus" sign has been added to each button. When the user clicks on the button, the "plus" sign is replaced with a "minus" sign.

Sliding accordions

The css


.accordion:after {
    content: '\02795'; /* Unicode character for "plus" sign (+) */
    font-size: 13px;
    color: #777;
    float: right;
    margin-left: 5px;
}

.active:after {
    content: "\2796"; /* Unicode character for "minus" sign (-) */
}

boxing day challenge please help to explain the js code used to build the animated accordion for better understanding

How to make animated accordions with symbols