<div class="data_list" v-for="(item,index) in data_list" :key="index">
    <input type="checkbox" class="check_box tui-checkbox" :id="'id'+item.id" :value="item.id" v-model="checkedNames">
    <label :for="'id'+item.id" class="title">{{item.title}}</label >
</div>

.tui-checkbox:checked {
  background: #1673ff;
  border: solid 1px #1673ff;
}
.tui-checkbox {
  width: 0.5rem;
  height: 0.5rem;
  background-color: #ffffff;
  border: solid 1px #dddddd;
  -webkit-border-radius: 50%;
  border-radius: 50%;
  font-size: 0.8rem;
  margin: 0;
  padding: 0;
  position: relative;
  display: inline-block;
  vertical-align: top;
  cursor: default;
  -webkit-appearance: none;
  -webkit-user-select: none;
  user-select: none;
  -webkit-transition: background-color ease 0.6s;
  transition: background-color ease 0.6s;
}
.tui-checkbox:checked::after {
  content: '';
  top: 0.1rem;
  left: 0.09rem;
  position: absolute;
  background: transparent;
  border: #fff solid 2px;
  border-top: none;
  border-right: none;
  height: 0.12rem;
  width: 0.25rem;
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -webkit-transform: rotate(-45deg);
  transform: rotate(-45deg);
}