style.css

.indicator-container {
  position: relative;
  width: 100px;
  height: 50px;
  padding: 10px 10px 0;
  overflow: hidden;
}
.indicator {
  position: relative;
  width: 100%;
  height: 100%;
  background: linear-gradient(to right, green, yellow, red);
  border: 1px solid #ccc;
  border-radius: 100px 100px 0 0;
}
.arrow,
.indicator-cut {
  position: absolute;
  bottom: 0;
  left: 50%;
  border-radius: 100px 100px 0 0;
}
.indicator-cut {
  width: 50px;
  height: 25px;
  background-color: #fff;
  border: 1px solid #ccc;
  transform: translateX(-50%);
}
.arrow {
  width: 3.5px;
  height: 55px;
  background-color: #000;
  transform-origin: bottom center;
  transform: translateX(-50%) rotate(-90deg);
  z-index: 1;
  box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.4);
}
.arrow.animate {
  transition: transform 1s 0.5s ease-in-out;
}