/* ============================================
   Flashcard Styles — 3D Flip Animation
   ============================================ */

.flashcard-area {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  padding: 1rem 0;
}

/* Card Container */
.card-wrapper {
  perspective: 1000px;
  width: 100%;
  max-width: 420px;
  height: 280px;
}

.flashcard {
  width: 100%;
  height: 100%;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
}

.flashcard.flipped {
  transform: rotateY(180deg);
}

.card-face {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  border-radius: var(--radius);
  border: 2px solid var(--border);
  background: var(--card-bg);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  text-align: center;
  gap: 0.75rem;
}

.card-front {
  border-top: 4px solid var(--primary);
}

.card-back {
  transform: rotateY(180deg);
  border-top: 4px solid var(--accent);
}

.card-face .word {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text);
}

.card-face .article {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--primary);
}

.card-face .example {
  font-size: 0.9rem;
  color: var(--text-light);
  font-style: italic;
  margin-top: 0.5rem;
}

.card-face .hint {
  font-size: 0.8rem;
  color: var(--text-light);
  margin-top: auto;
}

/* Navigation & Controls */
.card-controls {
  display: flex;
  gap: 0.75rem;
  width: 100%;
  max-width: 420px;
}

.card-controls .btn {
  flex: 1;
}

.card-nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  width: 100%;
  max-width: 420px;
  justify-content: space-between;
}

.card-counter {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-light);
}

/* Difficulty Rating Buttons */
.rating-buttons {
  display: flex;
  gap: 0.5rem;
  width: 100%;
  max-width: 420px;
}

.rating-buttons .btn {
  flex: 1;
  font-size: 0.85rem;
}

.btn-easy {
  background: var(--success);
  color: #fff;
}

.btn-hard {
  background: var(--accent);
  color: #fff;
}

.btn-forgot {
  background: var(--danger);
  color: #fff;
}

/* Box Indicator */
.box-indicator {
  display: flex;
  gap: 0.25rem;
  margin-bottom: 0.5rem;
}

.box-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--border);
  transition: background var(--transition);
}

.box-dot.active {
  background: var(--primary);
}

.box-dot.filled {
  background: var(--success);
}

/* Responsive */
@media (max-width: 768px) {
  .card-wrapper {
    height: 240px;
  }

  .card-face .word {
    font-size: 1.6rem;
  }
}