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HTML 

              
                <script>
  let holidayForm = function() {
  return {
    holidays: [
      {id: 'newyears', name: 'New Year', date: 'Jan 1'},
      {id: 'aprilfools', name: "April Fool's Day", date: 'Apr 1'},
      {id: 'juneteenth', name: 'Juneteenth', date: 'June 19'}
    ],
    selectedHolidays: [],
    toggleHoliday(id) {
      if (this.holidaySelected(id)) {
        this.selectedHolidays = this.selectedHolidays.filter(h => h !== id)
      } else {
        this.selectedHolidays.push(id)
      }

      this.$nextTick(() => console.log(this.$el.querySelector('input[name=selectedHolidays]').value))
    },
    holidaySelected(id) {
      return this.selectedHolidays.indexOf(id) > -1;
    }
  }
}
</script>


<form x-data="holidayForm()" class="block p-10">
  <label class="block text-xl">Your favorite holiday(s):</label>
  <div class="space-y-6">
    <template x-for="holiday in holidays">
      <div @click="toggleHoliday(holiday.id)" class="flex items-center">
        <div class="w-8 h-8 mr-3 border-2 border-gray-800">
          <svg x-cloak x-show="holidaySelected(holiday.id)" 
               viewBox="0 0 148 185" 
               xmlns="http://www.w3.org/2000/svg" 
               fill-rule="evenodd" 
               clip-rule="evenodd" 
               stroke-linejoin="round" 
               stroke-miterlimit="2">
            <path d="M42.24 153.673c-.736-3.425-1.52-6.861-2.499-10.287-3.75-13.125-6.336-27.497-12.973-39.665-3.552-6.512-8.024-12.371-12.112-18.503a8.004 8.004 0 00-11.094-2.219 8.004 8.004 0 00-2.219 11.094c3.827 5.739 8.054 11.195 11.378 17.29 6.077 11.141 8.202 24.38 11.636 36.398 2.057 7.201 3.213 14.454 4.958 21.53.504 2.045 1.184 4.177 1.684 6.177.36 1.441 1.393 4.234 1.393 4.234a8 8 0 0015.021-.129s1.324-3.808 2.285-5.57c2.202-4.036 4.402-7.991 6.368-12.169 6.24-13.258 13.433-25.884 20.896-38.478 21.532-36.336 37.88-79.472 68.126-109.719a8.004 8.004 0 000-11.314 8.003 8.003 0 00-11.313 0c-31.179 31.178-48.382 75.422-70.577 112.876-7.465 12.597-14.658 25.233-20.958 38.454z"/>
          </svg>
        </div>
        <div>
          <div class="font-bold" x-text="holiday.name"></div>
          <span class="block text-sm" x-text="holiday.date"></span>
        </div>
      </div>
    </template>
    <input x-model="selectedHolidays" type="hidden" name="selectedHolidays">
  </div>
</form>
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