<p class="under-dot-basic">点線の色、間隔を調整</p>
p{display:inline;}

/* 点線の間隔を調整 */
.under-dot-basic {
  background: linear-gradient(to left, #fff 0%, #fff 50%, #ff1481 50%, #ff1481 100%) repeat-x left bottom;
  background-size: 15px 1px;
}

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