Cube

<div class="left"></div>
<div class="right"></div>
<div class="bottom"></div>
<style>
  body {
    background: #0b2429;
    display: grid;
    align-content: center;
    justify-content: center;
  }
  div {
    width: 100px;
    height: 100px;
  }

  .bottom {
    background: #f3ac3c;
    grid-column: 1 / span 2;
    justify-self: center;
    rotate: 45deg;
  }

  .left,
  .right {
    width: 70px;
    height: 70px;
    translate: 0 15px;
  }

  .left {
    background: #998235;
    transform: skew(0deg, -45deg);
  }
  .right {
    background: #1a4341;
    transform: skew(0, 45deg);
  }
</style>