.flip-book-wrapper{
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.flip-book {
  background-color: white;
  background-size: cover;
  margin: 15px auto;
}

.page {
  padding: 20px;
  background-color: white;
  color: #333;
  border: solid 1px #ccc;
  overflow: hidden;
}

.page .page-content {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: stretch;
  background-color: white;
}

.page .page-content .page-image {
  height: 100%;
  background-size: contain;
  background-position: center center;
  background-repeat: no-repeat;
}

.page .page-content .page-text {
  flex-grow: 1;
  font-size: 80%;
  text-align: justify;
  margin-top: 10px;
  padding-top: 10px;
  box-sizing: border-box;
  background-color: white;
}

.page .page-content .page-footer {
  height: 30px;
  font-size: 80%;
  color: #555;
  background-color: white;
}

.page.--left,
.page.--right,
.page.hard,
.page.page-cover {
  background-color: white;
  border: solid 1px #ccc;
}

.page-cover-bottom, .page-content {
  background-color: #0dcaf0 !important;
}

.nav-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
}

.btn-nav {
  position: absolute;
  top: 0;
  width: 60px;
  height: 100%;
  cursor: pointer;
  transition: background 0.3s, transform 0.2s;
  z-index: 9999 !important;
  border-radius: 3px;
  border: solid 1px;
}

.btn-prev {
  left: calc(-8%);
}

.btn-next {
  right: calc(-8%);
}

.btn-nav:hover {
  transform: scaleX(1.2);
}

.btn-nav::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  border-style: solid;
  border-width: 10px 7px 10px 7px;
}

.btn-prev::before {
  border-color: transparent black transparent transparent;
  margin-left: 1px;
}

.btn-next::before {
  border-color: transparent transparent transparent black;
  margin-left: -1px;
}
.stf__wrapper{
  padding-bottom: 0 !important;
  z-index: 1 !important;
}

/* ===========================================
   Media Queries
=========================================== */

/* Large Desktop (≥1900px) */
@media screen and (min-width: 1900px) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
}

/* Standard Desktop / Laptop (1366px → 1899px) */
@media screen and (min-width: 1366px) and (max-width: 1899px) {
  .flip-book {
    width: 75vw;
    height: calc(75vw * 11 / 16);
  }
}

/* Small Laptop / Large Tablet (1024px → 1365px) */
@media screen and (min-width: 1024px) and (max-width: 1365px) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
  .btn-prev { left: calc(-10%); }
  .btn-next { right: calc(-10%); }
}

/* Tablet / iPad landscape (768px → 1023px) */
@media screen and (min-width: 768px) and (max-width: 1023px) and (orientation: landscape) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
  .btn-prev { left: calc(-10%); }
  .btn-next { right: calc(-10%); }
}

/* Tablet / iPad portrait (768px → 1023px) */
@media screen and (min-width: 768px) and (max-width: 1023px) and (orientation: portrait) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
}

/* Large Mobile landscape (480px → 767px) */
@media screen and (min-width: 480px) and (max-width: 767px) and (orientation: landscape) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
  .btn-prev { left: calc(-10%); }
  .btn-next { right: calc(-10%); }
}

/* Large Mobile portrait (480px → 767px) */
@media screen and (min-width: 480px) and (max-width: 767px) and (orientation: portrait) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
}

/* Small Mobile (<480px) */
@media screen and (max-width: 479px) {
  .flip-book {
    width: 70vw;
    height: calc(70vw * 11 / 16);
  }
  .btn-prev { left: calc(-10%); }
  .btn-next { right: calc(-10%); }
}