autonomic.zone/src/assets/styles/components/_box.scss

/* Box */

.box {
  border-radius: 3px;
  border: solid 2px _palette(border);
  margin-bottom: _size(element-margin);
  padding: 1.5em;

  > :last-child,
  > :last-child > :last-child,
  > :last-child > :last-child > :last-child {
    margin-bottom: 0;
  }

  &.alt {
    border: 0;
    border-radius: 0;
    padding: 0;
  }
}

/* Icon */

.icon--style1 { fill: _palette(bg); }
.icon--style2 { fill: _palette(accent2, bg); }
.icon--style3 { fill: _palette(accent3, bg); }
.icon--style4 { fill: _palette(accent4, bg); }

.icon--diamond {
  transform: rotate(-45deg);
  border-radius: 3px;
  border: 2px solid #dfdfdf;
  box-sizing: border-box;
  height: 5rem;
  width: 5rem;

  display: inline-flex;
  justify-content: center;
  align-items: center;
}

.icon--diamond svg {
  margin: 1rem;
  width: 2.25rem;
  transform: rotate(45deg);
}