html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
  font-family: Verdana, sans-serif;
}

.bg-layer {
  position: fixed;
  inset: 0;
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center;
  transition: opacity 1s ease-in-out;
  opacity: 0;
  z-index: -2;
}
#bg1 {
  opacity: 1;
}

.topbar {
  position: fixed;
  left: 0;
  top: 0;
  right: 0;
  height: 50px;
  background: #410303;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}
.topbar img {
  height: 36px;
}

.overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.7);
  color: #fff;
  font-size: 1.6rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
  z-index: 20;
}
.overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.menu {
  position: relative;
  top: 50px;
  height: calc(100vh - 50px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
@media (min-width: 768px) {
  .menu {
    flex-direction: row;
    overflow: hidden;
  }
}

.section {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: center;
  background: rgba(0, 0, 0, 0.28);
  color: #fff;
  cursor: pointer;
  transition: background 0.25s;
  overflow: hidden;
  border-left: #aaa dashed 1px;
  border-right: #aaa dashed 1px;
}
.section.active {
  background: rgba(0, 0, 0, 0.48);
  justify-content: flex-start;
}

.section h2 {
  margin: 0;
  padding: 14px 12px;
  color: #fff;
  font-size: 1.05rem;
  font-weight: 700;
  width: 100%;
  text-align: center;
  background: transparent;
}
.section.active h2 {
  display: none;
}

.items {
  display: none;
  width: 100%;
  flex-direction: column;
  box-sizing: border-box;
}
.section.active .items {
  display: flex;
}

@media (min-width: 768px) {
  .section {
    height: calc(100vh - 50px);
  }
  .items a {
    min-height: 140px;
  }
}

@media (max-width: 767px) {
  .menu {
    flex-direction: column;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    height: auto;
    min-height: calc(100vh - 50px);
  }
  .section {
    height: auto;
  }
  .items a {
    min-height: 120px;
  }
  .back-btn {
    display: block;
    background: rgba(0, 0, 0, 0.6);
    color: #fff;
    text-align: center;
    padding: 12px;
    cursor: pointer;
    font-weight: bold;
  }
}

.back-btn span {
  font-size: 1.2rem;
}

.items a {
  display: block;
  width: 100%;
  text-decoration: none;
  color: #fff;
  font-weight: 700;
  position: relative;
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 14px 16px;
  box-sizing: border-box;
}
.items a::after {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
}
.items a span {
  position: relative;
  z-index: 1;
}

.items a:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.18);
}

.modal {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 20;
}

.modal-content {
  position: relative;
  width: 90%;
  height: 90%;
  background: #ddd;
  display: flex;
  flex-direction: column;
}

.modal-top {
  background: #410303;
  padding: 10px;
  text-align: center;
}

.modal-back {
  color: white;
  background: none;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  font-family: Verdana, sans-serif;
}

#modal-frame {
  flex: 1;
  border: none;
  width: 100%;
}