/* Answer reveal mechanism */
.ans-hidden { display: none !important; }

.blank-space {
  display: inline-block;
  min-width: 80px;
  border-bottom: 2px dashed rgba(234,88,12,.45);
  background: rgba(234,88,12,.06);
  padding: 0 6px;
  color: rgba(234,88,12,.2);
  font-weight: 600;
  text-align: center;
  border-radius: 3px;
  transition: all .3s ease;
}
.blank-space.revealed {
  color: #e0af68;
  background: rgba(234,88,12,.14);
  border-bottom-color: rgba(234,88,12,.7);
}

.reveal-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #4f46e5;
  color: #fff;
  border: none;
  padding: 8px 22px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all .2s ease;
  margin-bottom: 14px;
  box-shadow: 0 2px 10px rgba(79,70,229,.3);
  font-family: inherit;
  letter-spacing: .02em;
}
.reveal-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 18px rgba(79,70,229,.4);
  background: #4338ca;
}
.reveal-btn:active { transform: translateY(0); }
.reveal-btn.active {
  background: #16a34a;
  box-shadow: 0 2px 10px rgba(22,163,74,.3);
}
.reveal-btn.active:hover {
  background: #15803d;
  box-shadow: 0 4px 18px rgba(22,163,74,.4);
}

/* Navigation buttons */
.nav-btn {
  position: fixed;
  top: 50%;
  transform: translateY(-50%);
  width: 52px;
  height: 52px;
  border-radius: 50%;
  border: none;
  background: rgba(79,70,229,.85);
  color: #fff;
  font-size: 28px;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: all .25s ease;
  box-shadow: 0 4px 20px rgba(0,0,0,.35);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  opacity: .7;
  line-height: 1;
  padding: 0;
}
.nav-btn:hover {
  opacity: 1;
  background: rgba(79,70,229,1);
  box-shadow: 0 6px 28px rgba(79,70,229,.5);
  transform: translateY(-50%) scale(1.1);
}
.nav-btn:active { transform: translateY(-50%) scale(1); }
.nav-btn-prev { left: 20px; }
.nav-btn-next { right: 20px; }
@media (max-width: 768px) {
  .nav-btn { width: 42px; height: 42px; font-size: 22px; }
  .nav-btn-prev { left: 10px; }
  .nav-btn-next { right: 10px; }
}