.bts-popup {
  position: fixed;
  z-index: 3;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow-y: auto;
  background-color: rgba(0, 0, 0, 0.5);

  display: flex;
  justify-content: center;
  align-items: center;
  text-align: center;

  opacity: 0;
  visibility: hidden;
  transition: opacity 0.35s ease, visibility 0.35s ease;
}

.bts-popup.is-visible {
  opacity: 1;
  visibility: visible;
}

.bts-popup-container {
  position: relative;
  width: 50%;
  max-width: 700px;
  margin: 2em auto;
  padding: 20px;

  background: #f9f1e5;
  border-radius: 5px;
  box-shadow: 10px 10px 5px black;
  text-align: center;

  opacity: 0;
  transform: translateY(-30px) scale(0.98);
  transition: opacity 0.35s ease-out, transform 0.35s ease-out;
  will-change: opacity, transform;
}

.is-visible .bts-popup-container {
  opacity: 1;
  transform: translateY(0) scale(1);
}

.bts-popup-container img {
  display: block;
  margin: 0 auto 20px auto;
}

.bts-popup-container p {
  margin: 15px 0;
  line-height: 1.5;
}

.bts-popup-container a {
  display: inline-block;
  margin: 15px 0;
  text-decoration: none;
  color: #007bff;
}

.bts-popup-container .bts-popup-button {
  display: inline-block;
  margin: 20px 0;
  padding: 10px 20px;
  border: 2px solid black;
  text-align: center;
}

.bts-popup-container .bts-popup-close {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 30px;
  height: 30px;
  cursor: pointer;
}

.bts-popup-container .bts-popup-close::before,
.bts-popup-container .bts-popup-close::after {
  content: "";
  position: absolute;
  top: 12px;
  width: 16px;
  height: 3px;
  background-color: black;
}

.bts-popup-container .bts-popup-close::before {
  left: 8px;
  transform: rotate(45deg);
}

.bts-popup-container .bts-popup-close::after {
  right: 6px;
  transform: rotate(-45deg);
}