モーダルダイアログ

.modal {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 1050;
  display: none;
  overflow: hidden;
  outline: 0;
}

.modal-dialog {
  position: relative;
  width: auto;
  margin: 0.5rem;
  pointer-events: none;
}

.modal.fade .modal-dialog {
  transition: -webkit-transform 0.3s ease-out;
  transition: transform 0.3s ease-out;
  transition: transform 0.3s ease-out, -webkit-transform 0.3s ease-out;
  -webkit-transform: translate(0, -25%);
  transform: translate(0, -25%);
}
        
.modal-content {
  position: relative;
  display: -ms-flexbox;
  display: flex;
  -ms-flex-direction: column;
  flex-direction: column;
  width: 100%;
  pointer-events: auto;
  background-color: #fff;
  background-clip: padding-box;
  border: 1px solid rgba(0, 0, 0, 0.2);
  border-radius: 0.3rem;
  outline: 0;
}

.modal-header {
  display: -ms-flexbox;
  display: flex;
  -ms-flex-align: start;
  align-items: flex-start;
  -ms-flex-pack: justify;
  justify-content: space-between;
  padding: 1rem;
  border-bottom: 1px solid #e9ecef;
  border-top-left-radius: 0.3rem;
  border-top-right-radius: 0.3rem;
}

.modal-header .close {
  padding: 1rem;
  margin: -1rem -1rem -1rem auto;
}
        
.close {
  float: right;
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  color: #000;
  text-shadow: 0 1px 0 #fff;
  opacity: .5;
}

.close:hover, .close:focus {
  color: #000;
  text-decoration: none;
  opacity: .75;
}

.modal-title {
  margin-bottom: 0;
  line-height: 1.5;
}

.modal-body {
  position: relative;
  -ms-flex: 1 1 auto;
  flex: 1 1 auto;
  padding: 1rem;
}

.modal-footer {
  display: -ms-flexbox;
  display: flex;
  -ms-flex-align: center;
  align-items: center;
  -ms-flex-pack: end;
  justify-content: flex-end;
  padding: 1rem;
  border-top: 1px solid #e9ecef;
}