CodePen Embed - Modal Overlay in JS

<!DOCTYPE html>
<html lang = 'en'>
    <head>
        <meta charset = 'UTF-8'>
        <meta name = 'viewport' content = 'width=device-width, initial-scale=1.0'>
        <title>JS Modal Overlay</title>
        <link rel = 'stylesheet' href = 'index.css'>
        <script src = 'index.js' defer></script>
    </head>
    <body>
        <div class = 'box'>
            <h3>Click the button below to show the modal</h3>
            <button class = 'button show-modal-button'>Click</button>
        </div>
    </body>
</html>

:root {
  --click-button: rgb(41, 160, 140);
  --hover-click-button: rgb(17, 151, 129);
  --button-okay: #218199;
  --button-okay-hover: #10657a;
  --button-cancel-hover: #eafcff;
  --white: #ffffff;
  --black: #000000;
  --gray: #b4b4b4;
}

* {
  box-sizing: border-box;
}

body {
  font-family: sans-serif;
  margin: 5rem;
}

.box {
  background-color: var(--white);
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  padding: 1rem;
  width: 26rem;
}

.modal-header {
  padding: 0.7rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--gray);
}

.modal-title {
  font: inherit;
  font-size: 1.2rem;
}

.button-close {
  background-color: transparent;
  border: none;
  outline: none;
}

.close-icon {
  opacity: 0.3;
  cursor: pointer;
}

.close-icon:hover {
  opacity: 1;
}

.close-icon:before,
.close-icon:after {
  content: "";
  position: absolute;
  height: 20px;
  width: 3px;
  background-color: var(--black);
  top: 13px;
}

.close-icon:before {
  transform: rotate(45deg);
}

.close-icon::after {
  transform: rotate(-45deg);
}

.modal-body {
  padding: 0.7rem 1.5rem;
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  border-top: 1px solid var(--gray);
  padding: 0.7rem 1.5rem;
}

.button {
  font: inherit;
  padding: 0.6rem 1.2rem;
  border-radius: 5px;
  cursor: pointer;
  font-weight: bold;
}

.show-modal-button {
  background-color: var(--click-button);
  border: 1px solid var(--click-button);
  color: var(--white);
  margin: 1rem 1rem 0 0;
}

.show-modal-button:hover {
  background-color: var(--hover-click-button);
  border-color: var(--hover-click-button);
}

.button-okay {
  background-color: var(--button-okay);
  color: var(--white);
}

.button-okay:hover {
  background-color: var(--button-okay-hover);
}

.button-cancel {
  color: var(--button-okay);
  background-color: transparent;
  border: 1px solid var(--button-okay);
  margin-right: 0.6rem;
}

.button-cancel:hover {
  background-color: var(--button-cancel-hover);
}

.modal {
  position: fixed;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.35);
  border-radius: 8px;
  background-color: var(--white);
  width: 30rem;
  z-index: 10;
  top: 30vh;
  left: calc(50% - 15rem);
}

.backdrop {
  position: fixed;
  z-index: 1;
  background-color: rgba(0, 0, 0, 0.75);
  width: 100%;
  height: 100vh;
  top: 0;
  left: 0;
}

const button = document.querySelector("button");

button.addEventListener("click", showModalHandler);

let modal;
let backdrop;

function showModalHandler() {
  if (modal) {
    return;
  }

  modal = document.createElement("div");
  modal.className = "modal";

  const modalHeader = document.createElement("div");
  modalHeader.className = "modal-header";

  const modalBody = document.createElement("div");
  modalBody.className = "modal-body";

  const modalFooter = document.createElement("div");
  modalFooter.className = "modal-footer";

  const modalTitle = document.createElement("div");
  modalTitle.textContent = "Modal Title";
  modalTitle.className = "modal-title";

  const modalContent = document.createElement("p");
  modalContent.textContent = "Here is the simple modal overlay made with js!";

  const modalActionYes = document.createElement("button");
  const modalActionCancel = document.createElement("button");
  const modalClose = document.createElement("button");
  const closeIcon = document.createElement("div");

  modalActionYes.textContent = "Okay";
  modalActionCancel.textContent = "Cancel";

  modalActionYes.addEventListener("click", modalCloseHandler);
  modalActionCancel.addEventListener("click", modalCloseHandler);
  modalClose.addEventListener("click", modalCloseHandler);

  modalActionYes.className = "button button-okay";
  modalActionCancel.className = "button button-cancel";
  modalClose.className = "button-close";
  closeIcon.className = "close-icon";

  modalClose.append(closeIcon);
  modalHeader.append(modalTitle);
  modalHeader.append(modalClose);
  modalBody.append(modalContent);
  modalFooter.append(modalActionCancel);
  modalFooter.append(modalActionYes);

  modal.append(modalHeader);
  modal.append(modalBody);
  modal.append(modalFooter);

  document.body.append(modal);

  backdrop = document.createElement("div");

  backdrop.className = "backdrop";

  backdrop.addEventListener("click", modalCloseHandler);

  document.body.append(backdrop);
}

function modalCloseHandler() {
  modal.remove();
  modal = null;

  backdrop.remove();
  backdrop = null;
}

This Pen is owned by Saba Alikhani on CodePen.

See more by @fydsa on CodePen

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