<main class="container">
  <section class="section section1"> <button class="modal__btn modal__btn-primary" data-micromodal-trigger="modal-1" role="button">モーダルを開く</button></section>

  <!-- ここからモーダルエリアです。 -->
  <div class="modal micromodal-slide" id="modal-1" aria-hidden="true">
    <div class="modal__overlay" tabindex="-1" data-micromodal-close>
      <div class="modal__container" role="dialog" aria-modal="true" aria-labelledby="modal-1-title">
        <div role="document">
          <header class="modal__header">
            <h2 class="modal__title" id="modal-1-title">
              モーダルとは
            </h2>
            <button class="modal__close" aria-label="Close modal" data-micromodal-close></button>
          </header>
          <main class="modal__content" id="modal-1-content">
            <p>モーダルウィンドウとは、操作が完了するまで親ウィンドウへの操作を受け付けなくさせるタイプのウィンドウです。こちらの例では、コンテンツを浮かび上がるように表示しています。</p>
          </main>
          <footer class="modal__footer">
            <button class="modal__btn modal__btn-primary" data-micromodal-close aria-label="Close this dialog window">わかった！</button>
          </footer>
        </div>
      </div>
    </div>
  </div>
</main>

* {
  box-sizing: border-box;
}

.section {
  height: 100vh;
}
.section1 {
  background-color: #ccccff;
  display: flex;
  justify-content: center;
  align-items: center;
}
.section2 {
  background-color: #99ccff;
}
.section3 {
  background-color: #ffccff;
}

/**************************\
  Basic Modal Styles
\**************************/

.modal {
  font-family: -apple-system, BlinkMacSystemFont, avenir next, avenir,
    helvetica neue, helvetica, ubuntu, roboto, noto, segoe ui, arial, sans-serif;
}

.modal__overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.6);
  display: flex;
  justify-content: center;
  align-items: center;
}

.modal__container {
  background-color: #fff;
  padding: 30px;
  max-width: 500px;
  max-height: 100vh;
  border-radius: 4px;
  overflow-y: auto;
  box-sizing: border-box;
}

@media screen and (max-width: 480px) {
  .modal__container {
    max-height: 90vh;
    max-width: 300px;
  }
}

.modal__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal__title {
  margin-top: 0;
  margin-bottom: 0;
  font-weight: 600;
  font-size: 1.25rem;
  line-height: 1.25;
  color: #00449e;
  box-sizing: border-box;
}

.modal__close {
  background: transparent;
  border: 0;
}

.modal__header .modal__close:before {
  content: "\2715";
}

.modal__content {
  margin-top: 2rem;
  margin-bottom: 2rem;
  line-height: 1.5;
  color: rgba(0, 0, 0, 0.8);
}

.modal__btn {
  font-size: 0.875rem;
  padding-left: 1rem;
  padding-right: 1rem;
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
  background-color: #e6e6e6;
  color: rgba(0, 0, 0, 0.8);
  border-radius: 0.25rem;
  border-style: none;
  border-width: 0;
  cursor: pointer;
  -webkit-appearance: button;
  text-transform: none;
  overflow: visible;
  line-height: 1.15;
  margin: 0;
  will-change: transform;
  -moz-osx-font-smoothing: grayscale;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  -webkit-transform: translateZ(0);
  transform: translateZ(0);
  transition: -webkit-transform 0.25s ease-out;
  transition: transform 0.25s ease-out;
  transition: transform 0.25s ease-out, -webkit-transform 0.25s ease-out;
}

.modal__btn:focus,
.modal__btn:hover {
  -webkit-transform: scale(1.05);
  transform: scale(1.05);
}

.modal__btn-primary {
  background-color: #00449e;
  color: #fff;
}

/**************************\
  Demo Animation Style
\**************************/
@keyframes mmfadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes mmfadeOut {
  from {
    opacity: 1;
  }
  to {
    opacity: 0;
  }
}

@keyframes mmslideIn {
  from {
    transform: translateY(15%);
  }
  to {
    transform: translateY(0);
  }
}

@keyframes mmslideOut {
  from {
    transform: translateY(0);
  }
  to {
    transform: translateY(-10%);
  }
}

.micromodal-slide {
  display: none;
}

.micromodal-slide.is-open {
  display: block;
}

.micromodal-slide[aria-hidden="false"] .modal__overlay {
  animation: mmfadeIn 0.3s cubic-bezier(0, 0, 0.2, 1);
}

.micromodal-slide[aria-hidden="false"] .modal__container {
  animation: mmslideIn 0.3s cubic-bezier(0, 0, 0.2, 1);
}

.micromodal-slide[aria-hidden="true"] .modal__overlay {
  animation: mmfadeOut 0.3s cubic-bezier(0, 0, 0.2, 1);
}

.micromodal-slide[aria-hidden="true"] .modal__container {
  animation: mmslideOut 0.3s cubic-bezier(0, 0, 0.2, 1);
}

.micromodal-slide .modal__container,
.micromodal-slide .modal__overlay {
  will-change: transform;
}

MicroModal.init({
  awaitCloseAnimation: true,
  awaitOpenAnimation: true,
  disableScroll: true
});