Result

2色や3色など、色とりどりな点線をlinear-gradientで引いています

css

.block {/*基本設定*/
  background-color: #FFF;
  height: 20px;
  margin-bottom: 20px;
  position: relative;
}
.block:before {
  bottom: 0;
  content: '';
  height: 10px;
  position: absolute;
  width: 100%;
}
.block-one:before {/*疑似要素に複数グラデーションを設定していく*/
  background-size: 60px 100%;
  background-color: #ccc69a;
  background-image: linear-gradient(left, transparent 0%, transparent 25%, #89a193 25%, #89a193 50%, transparent 50%, transparent 75%, #cc8734 75%, #cc8734 100%);
}
.block-two:before {
  background-size: 30px 100%;
  background-color: #e8e6d6;
  background-image: linear-gradient(left, transparent 0%, transparent 25%, #655f6a 25%, #655f6a 50%, transparent 50%, transparent 75%, #bb7761 75%, #bb7761 100%);
}
.block-three:before {
  background-size: 10px 100%;
  background-color: #d7b2b5;
  background-image: linear-gradient(left, transparent 0%, transparent 50%, #bb7761 50%, #bb7761 100%);
}
.block-four:before {
  background-size: 120px 100%;
  background-color: #ccc69a;
  background-image: linear-gradient(left, transparent 0%, transparent 25%, #737258 25%, #737258 50%, transparent 50%, transparent 75%, #bb7761 75%, #bb7761 100%);
}
.block-five:before {
  background-size: 120px 100%;
  background-color: #655f6a;
  background-image: linear-gradient(left, transparent 0%, transparent 50%, #e8e6d6 50%, #e8e6d6 100%);
}

html

<div class="container">
  <div class="block block-one"></div>
  <div class="block block-two"></div>
  <div class="block block-three"></div>
  <div class="block block-four"></div>
  <div class="block block-five"></div>
</div>

via

Striped gradient borders