one <div>

Star

Three triangles: the div itself plus two rotated pseudo-elements.

HTML + CSS
<div class="od od-star"></div>

.od {
  position: relative;
  display: block;
  box-sizing: border-box;
}
.od::before,
.od::after {
  content: '';
  position: absolute;
  box-sizing: border-box;
}

.od-star {
  width: 0; height: 0;
  border-left: 36px solid transparent;
  border-right: 36px solid transparent;
  border-bottom: 26px solid #f5b301;
  transform: translateY(-8px);
  filter: drop-shadow(0 8px 16px rgba(245, 179, 1, 0.35));
}
.od-star::before {
  width: 0; height: 0;
  border-left: 36px solid transparent;
  border-right: 36px solid transparent;
  border-bottom: 26px solid #f5b301;
  top: 8px; left: -36px; transform: rotate(72deg);
}
.od-star::after {
  width: 0; height: 0;
  border-left: 36px solid transparent;
  border-right: 36px solid transparent;
  border-bottom: 26px solid #f5b301;
  top: 8px; left: -36px; transform: rotate(-72deg);
}