Images clipping out of tiles on an isometric grid

Question

I have an isometric table setup as:

<table style="transform: rotateX(60deg) rotateZ(45deg); border-spacing: 0px">
  <tr style="transform: translateY(0em)"> <!-- For first row, future rows get translated down -->
    <td style="transform: translateX(0em)"> <!-- For first column, future columns get translated down -->
      <div class="tile">
        <div class="background"></div>
      </div>
    </td>
  </tr>
</table>

With the following CSS:

.tile {
  transform: translate3d(0em, 0em, 0em);
  width: 4em;
  height: 4em;
}

.background {
  height: calc(28.75em);
  width: calc(28.75em);
  background-size: 100%;
  background-image: url("/tiles/robot2/facing_north.png"), url("/tiles/plain_4/facing_east.png");
}

It produces a little robot standing on a tile as so:

However, the robot is off-centre. So, wanting to centre it I add the following CSS:

.background {
  background-position-y: -3em, 0em;
}

This moves the robot up, but doesn't move the tile up, which is perfect! Except, I seem to get some cutting off of the robots head:

How can I move the robot up so that it looks to be centred on the tile without clipping off the top of it's head? I've tried overflow: visible; to no avail.

Example:

.container {
  position: relative;
  z-index: 10;
}

.iso {
  transform: rotateX(60deg) rotateZ(45deg);
  position: absolute;
  border-spacing: 0px;
  left: 200.0px;
  top: 100.0px;
}

.tile {
  transform: translate3d(0em, 0em, 0em);
  width: 4em;
  height: 4em;
}

.background {
  transform: rotateZ(-45deg) rotateY(-60deg) translate3d(-1.1em, -4.8em, 0em);
  height: calc(23em);
  width: calc(23em);
  background-size: 100%;
  background-image: url("https://femto.pw/us7j.png"), url("https://femto.pw/r44h.png");
  background-position-y: -2.5em, 0em;
  background-repeat: no-repeat;
}

<div class="container">
  <table class="iso">
    <tbody>
      <tr class="row--5 row" style="transform: translateY(0em);">
        <td class="col--5 iso_td" style="transform: translateX(0em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
        <td class="col--4 iso_td" style="transform: translateX(4em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
      </tr>
      <tr class="row--4 row" style="transform: translateY(4em);">
        <td class="col--5 iso_td" style="transform: translateX(0em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
        <td class="col--4 iso_td" style="transform: translateX(4em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
      </tr>
    </tbody>
  </table>
</div>

Answer 1

.container {
  position: relative;
  z-index: 10;
}

.iso {
  transform: rotateX(60deg) rotateZ(45deg);
  position: absolute;
  border-spacing: 0px;
  left: 200.0px;
  top: 100.0px;
}

.tile {
  transform: translate3d(0em, 0em, 0em);
  width: 4em;
  height: 4em;
}

.background {
  transform: rotateZ(-45deg) rotateY(-60deg) translate3d(-1.1em, -4.8em, 0em);
  height: calc(23em);
  width: calc(23em);
  background-size: 100%;
  background-image: url("https://femto.pw/r44h.png");
  background-position-y: -2.5em, 0em;
  background-repeat: no-repeat;
  position: relative;
}
.background::before{
content: '';
position: absolute;
top: -80px;
bottom: 0;
left: 0;
right: 0;
background-image: url("https://femto.pw/us7j.png");
background-size: contain;
background-repeat: no-repeat;
}

<div class="container">
  <table class="iso">
    <tbody>
      <tr class="row--5 row" style="transform: translateY(0em);">
        <td class="col--5 iso_td" style="transform: translateX(0em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
        <td class="col--4 iso_td" style="transform: translateX(4em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
      </tr>
      <tr class="row--4 row" style="transform: translateY(4em);">
        <td class="col--5 iso_td" style="transform: translateX(0em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
        <td class="col--4 iso_td" style="transform: translateX(4em);">
          <div class="tile">
            <div class="background"></div>
          </div>
        </td>
      </tr>
    </tbody>
  </table>
</div>