static/style.css

.subgrid {
  grid-column: screen; 
  display: grid; 
  grid-template-columns: inherit;
  grid-template-rows: inherit;
  grid-column-gap: inherit;
  grid-row-gap: inherit;
}

d-figure.base-grid {
  grid-column: screen;
  background: hsl(0, 0%, 97%);
  padding: 20px 0;
  border-top: 1px solid rgba(0, 0, 0, 0.1);
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

d-figure {
  margin-bottom: 1em;
  position: relative;
}

d-figure > figure {
  margin-top: 0;
  margin-bottom: 0;
}

.shaded-figure {
  background-color: hsl(0, 0%, 97%);
  border-top: 1px solid hsla(0, 0%, 0%, 0.1);
  border-bottom: 1px solid hsla(0, 0%, 0%, 0.1);
  padding: 30px 0;
}

.pointer {
  position: absolute;
  width: 26px;
  height: 26px;
  top: 26px;
  left: -48px;
}