CSS의 화살표 스트라이프

화살표(아래)

<div class="arrow"></div>

.arrow {
  position: relative;
}
.arrow::before {
  content: "";
  display: block;
  position: absolute;
  top: 0px;
  left: 50%;
  width: 0;
  height: 0;
  transform: translateX(-50%);
  border: 12px solid transparent;
  border-top: 12px solid #000;
  border-bottom-width: 0;
}

  border-left: 12px solid #000;
  border-right-width: 0;

선 화살표(아래)

<div class="arrow"></div>

.arrow {
    position: relative;
}
.arrow::before {
  content: "";
  display: block;
  position: absolute;
  top: 0;
  right: 50%;
  width: 14px;
  height: 14px;
  border-top: 2px solid #000;
  border-right: 2px solid #000;
  transform: translateX(-50%) rotate(135deg);
}

 transform: translateX(-50%) rotate(45deg);