How to change + icon to - icon when span is clicked?

Question

https://code.sololearn.com/W4Y3LcW4MTVD/?ref=app

Answer 1

const span=document.getElementsByTagName("span");
for(let i=0; i<span.length; i++){
span[i].onclick=function (){
const content=document.querySelectorAll(".content");
for(let j=0; j<content.length; j++){
if(j===i)
content[j].classList.toggle("show")
else
content[j].classList.add("show")
}
}
}
// in addition will be needed to set the start positions of the spans for example using css

Answer 2

JaScript thanks but my problem is the - icon
I want + icon be replaced with -icon while toggling spans