Designing play buttons, Removing z-index

Design & UX
1

I’m trying to figure out how to remove z-index from the play/pause buttons.

.playd,
.paused {
  position: absolute;
  top: -4px;
  right: 0;
  bottom: 0;
  left: 4px;
  margin: auto;
  fill: #0059dd;
  z-index: 2;
}

I just figured out how to do it.

.image::before,
.image::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  background: url("https://i.imgur.com/ZmbeHHW.png") no-repeat center;
  border-radius: 50%;
  width: 170px;
  height: 170px;
}

.image::after {
  background: url("https://i.imgur.com/4HJbzEq.png") no-repeat;
  width: 180px;
  height: 180px;
}

<div class="playButtond" data-audio="http://hi5.1980s.fm/;">
  <div class="image"></div>

1.)
And here I managed to remove all of the z-indexes:
https://jsfiddle.net/hk8q4ugw/5/

.playButtond {
  position: relative;
  width: 266px;
  height: 200px;
  cursor: pointer;
  border: 3px solid #0059dd;
  box-sizing: border-box;
}

.image::before,
.image::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  background: url("https://i.imgur.com/ZmbeHHW.png") no-repeat center;
  border-radius: 50%;
  width: 170px;
  height: 170px;
}

.image::after {
  background: url("https://i.imgur.com/4HJbzEq.png") no-repeat;
  width: 180px;
  height: 180px;
}

.playd,
.paused {
  position: absolute;
  top: -4px;
  right: 0;
  bottom: 0;
  left: 4px;
  margin: auto;
  fill: #0059dd;
}

.paused {
  left: 0;
}

.linesd::before,
.linesd::after {
  content: "";
  position: absolute;
  top: 0;
  left: 83px;
  width: 3px;
  height: 100%;
  background: #0059dd;
}

.linesd::after {
  left: 174px;
}

.hided {
  display: none;
}

2.)
The one with the border now only needs 1 z-index:
https://jsfiddle.net/hk8q4ugw/46/

.playd,
.paused {
  position: absolute;
  top: -4px;
  right: 0;
  bottom: 0;
  left: 4px;
  z-index: 1;
  margin: auto;
  fill: #0059dd;
}

3.)
Tooltips now works on hover:
https://jsfiddle.net/hk8q4ugw/50/


.playButtond {
  position: relative;
  width: 266px;
  height: 200px;
  cursor: pointer;
  border: 3px solid #0059dd;
  box-sizing: border-box;
}

.image::before,
.image::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  background: url("https://i.imgur.com/ZmbeHHW.png") no-repeat center;
  border-radius: 50%;
  width: 170px;
  height: 170px;
}

.image::after {
  background: url("https://i.imgur.com/4HJbzEq.png") no-repeat;
  width: 180px;
  height: 180px;
}

.stack {
  position: relative;
  stroke-width: 2;
  stroke: green;
  fill: transparent;
}

.playButtond:hover .stack {
  stroke: red;
}

.playd,
.paused {
  position: absolute;
  top: -4px;
  right: 0;
  bottom: 0;
  left: 4px;
  z-index:1;
  margin: auto;
  fill: #0059dd;
}

.paused {
  left: 0;
}

.linesd::before,
.linesd::after {
  content: "";
  position: absolute;
  top: 0;
  left: 83px;
  width: 3px;
  height: 100%;
  background: #0059dd;
}

.linesd::after {
  left: 174px;
}

.hided {
  display: none;
}

4.)
I just completely removed z-index from the safe code.
https://jsfiddle.net/v19fmpy8/17/


.image {
  position: relative;
  cursor: pointer;
  border: 3px solid #0059dd;
  box-sizing: border-box;
  width: 266px;
  height: 251px;
  background: url("https://i.imgur.com/qaEvk4G.png") no-repeat;
}

.lines::before,
.lines::after {
  content: "";
  position: absolute;
  top: 0;
  left: 83px;
  width: 3px;
  height: 100%;
  background: #0059dd;
}

.lines::after {
  left: 174px;
}

.stack {
  position: relative;
  stroke-width: 6;
  stroke: #89cff0;
}

.playf,
.pausef {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 14px;
  margin: auto;
  fill: #0059dd;
  
}

.pausef {
  left: 10px;
}

.hidef {
  display: none;
}

5.)
I just removed z-index from the 2 lines from this code.
https://jsfiddle.net/27txbnj0/4/

6.)
I just realized soon after I can simplify it even more.

By doing this.

<div class="playButtonf image" data-audio="http://hi5.1980s.fm/;">
https://jsfiddle.net/v19fmpy8/23/

Are there any other optimizations I should do?