Multiple Modal Vanilla

modal.html

<div class="modal" id="modal-1">
  <div class="modal-box">
    <div class="modal-close">
      <div class="icon-close"></div>
    </div>
    <div>
      <!-- content -->
    </div>
  </div>
</div>

modal.js

const OpenModal = document.querySelectorAll('.open-modal')

if (OpenModal) {
  const elemtModal = document.querySelectorAll('.modal')
  const elemtModalBox = document.querySelectorAll('.modal-box')
  const modalClose = document.querySelectorAll('.modal-close')

  let modals = []

  function seachModalActive (idDelete) {
    for (let i = 0; i < modals.length; i++) {
      if (modals[i] === idDelete) {
        modals.splice(i, 1);
      }
    }
    if (modals.length === 0) {
      document.body.style.overflow = ''
    }
  }

  // Open Modals
  for (let i = 0; i < OpenModal.length; i++) {
    OpenModal[i].addEventListener('click', (e) => {
      e.preventDefault()
      const idModalActive = e.target.dataset['idModal']
      document.getElementById(idModalActive).classList.add('active')
      document.body.style.overflow = 'hidden'
      modals.push(idModalActive)
    })
  }

  // Close Modals
  for (let i = 0; i < elemtModal.length; i++) {
    elemtModalBox[i].addEventListener('click', (e) => {
      e.stopPropagation()
    })
    elemtModal[i].addEventListener('click', () => {
      elemtModal[i].classList.remove('active')
      const idModal = elemtModal[i].getAttribute('id')
      seachModalActive(idModal)
    })
    modalClose[i].addEventListener('click', (e) => {
      const fatherModal = e.target.parentElement.parentElement.parentElement
      const idModalClose = e.target.parentElement.parentElement.parentElement.getAttribute('id')
      fatherModal.classList.remove('active')
      seachModalActive(idModalClose)
    })
  }
}

modal.scss

.modal {
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  width: 100%;
  background-color: transparentize(#000, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px 15px;
  z-index: 1000;
  overflow: auto;
  margin: 0 auto;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  @media (min-width: 768px) {
    background-color: transparentize(#000, 0.4);
  }

  &.active {
    opacity: 1;
    visibility: visible;

    .modal {
      &-box {
        transform: scale(1);
      }
    }
  }

  &-box {
    position: relative;
    border-radius: 4px;
    overflow: hidden;
    margin: auto;
    transition: all 0.3s;
    transform: scale(0.7);
  }

  &-close {
    position: absolute;
    top: 0;
    right: 0;
    z-index: 10;

    .icon-close {
      transform: scale(0.8);

      &:before, &:after {
        background-color: #ffffff;
      }
    }
  }
}