element-plus/docs/examples/date-picker/custom-content.vue

<template>
  <div class="demo-date-picker">
    <el-date-picker
      v-model="value"
      type="date"
      placeholder="Pick a day"
      format="YYYY/MM/DD"
      value-format="YYYY-MM-DD"
    >
      <template #default="cell">
        <div class="cell" :class="{ current: cell.isCurrent }">
          <span class="text">{{ cell.text }}</span>
          <span v-if="isHoliday(cell)" class="holiday"></span>
        </div>
      </template>
    </el-date-picker>
  </div>
</template>

<script lang="ts" setup>
import { ref } from 'vue'

const value = ref('2021-10-29')
const holidays = [
  '2021-10-01',
  '2021-10-02',
  '2021-10-03',
  '2021-10-04',
  '2021-10-05',
  '2021-10-06',
  '2021-10-07',
]

const isHoliday = ({ dayjs }) => {
  return holidays.includes(dayjs.format('YYYY-MM-DD'))
}
</script>

<style scoped>
.cell {
  height: 30px;
  padding: 3px 0;
  box-sizing: border-box;
}
.cell .text {
  width: 24px;
  height: 24px;
  display: block;
  margin: 0 auto;
  line-height: 24px;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 50%;
}
.cell.current .text {
  background: purple;
  color: #fff;
}
.cell .holiday {
  position: absolute;
  width: 6px;
  height: 6px;
  background: red;
  border-radius: 50%;
  bottom: 0px;
  left: 50%;
  transform: translateX(-50%);
}
</style>