/* =============================================
   Flashcards Page
   ============================================= */

.fc-wrap {
  padding-top: 40px;
  padding-bottom: 80px;
  display: grid;
  grid-template-columns: 1fr 240px;
  grid-template-rows: auto auto 1fr;
  column-gap: 28px;
  row-gap: 20px;
  align-items: start;
}

/* ── CONTROLS ── */
.fc-controls {
  grid-column: 1 / -1;
  display: flex;
  align-items: flex-end;
  gap: 20px;
  flex-wrap: wrap;
}

.fc-ctrl-group {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.fc-ctrl-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: var(--gray-500);
}

.fc-select-wrap {
  min-width: 180px;
}

.fc-topic-group { flex: 1; max-width: 280px; }

.fc-option-row {
  display: flex;
  gap: 8px;
}

.fc-opt-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 14px;
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-md);
  background: var(--white);
  font-family: var(--font);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--gray-600);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.fc-opt-btn:hover {
  border-color: var(--green-400);
  color: var(--green-700);
  background: var(--green-50);
}

.fc-opt-btn.active {
  background: var(--green-600);
  border-color: var(--green-600);
  color: white;
}

/* ── PROGRESS BAR ── */
.fc-progress-wrap {
  grid-column: 1;
}

.fc-progress-labels {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
  font-size: 0.82rem;
  color: var(--gray-500);
  font-weight: 500;
}

.fc-legend {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.78rem;
}

.fc-legend span { display: flex; align-items: center; gap: 5px; }

.fc-legend-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.dot-known  { background: var(--green-500); }
.dot-review { background: #f59e0b; }

.fc-progress-track {
  height: 8px;
  background: var(--gray-100);
  border-radius: 100px;
  overflow: hidden;
  display: flex;
}

.fc-progress-known {
  height: 100%;
  background: var(--green-500);
  border-radius: 100px;
  transition: width 0.5s ease;
  flex-shrink: 0;
}

.fc-progress-current {
  height: 100%;
  background: var(--gray-300);
  border-radius: 100px;
  transition: width 0.5s ease;
  flex-shrink: 0;
}

/* ── CARD STAGE ── */
.fc-stage {
  grid-column: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.fc-filter-tabs {
  display: flex;
  gap: 4px;
  align-self: flex-start;
  background: var(--gray-100);
  border-radius: var(--radius-md);
  padding: 4px;
}

.fc-tab {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 14px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--gray-500);
  background: transparent;
  transition: all var(--transition);
  white-space: nowrap;
}

.fc-tab.active {
  background: var(--white);
  color: var(--green-700);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--gray-200);
}

.fc-tab-badge {
  font-size: 0.7rem;
  font-weight: 800;
  padding: 1px 6px;
  border-radius: 100px;
  background: #fef3c7;
  color: #92400e;
  min-width: 18px;
  text-align: center;
}

.fc-tab-badge-green {
  background: var(--green-100);
  color: var(--green-800);
}

/* ── THE FLIP CARD ── */
.fc-card-wrap {
  width: 100%;
  max-width: 640px;
  height: 340px;
  perspective: 1200px;
  cursor: pointer;
}

.fc-card {
  width: 100%;
  height: 100%;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 0.55s cubic-bezier(0.4, 0.2, 0.2, 1);
}

.fc-card.flipped {
  transform: rotateY(180deg);
}

.fc-face {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: var(--radius-xl);
  padding: 36px 40px;
  display: flex;
  flex-direction: column;
  border: 1.5px solid var(--gray-100);
}

/* Front face */
.fc-front {
  background: var(--white);
  justify-content: center;
  align-items: center;
  text-align: center;
}

/* Back face — rotated 180 so it appears correct when card is flipped */
.fc-back {
  background: var(--white);
  transform: rotateY(180deg);
  justify-content: flex-start;
  overflow-y: auto;
}

[data-theme="dark"] .fc-face {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.1);
}

.fc-topic-badge {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--green-700);
  background: var(--green-50);
  border: 1px solid var(--green-200);
  padding: 4px 10px;
  border-radius: 100px;
  margin-bottom: 20px;
  align-self: flex-start;
}

[data-theme="dark"] .fc-topic-badge {
  color: #86efac;
  background: rgba(22,163,74,0.15);
  border-color: rgba(22,163,74,0.3);
}

.fc-term {
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--gray-900);
  line-height: 1.2;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

[data-theme="dark"] .fc-term { color: #f1f5f9; }

.fc-flip-hint {
  font-size: 0.8rem;
  color: var(--gray-400);
  display: flex;
  align-items: center;
  gap: 6px;
}

.fc-flip-hint::before {
  content: '↕';
  font-size: 1rem;
}

.fc-definition {
  font-size: 1rem;
  color: #1f2937;
  line-height: 1.7;
  font-weight: 400;
  flex: 1;
}

[data-theme="dark"] .fc-definition { color: #e2e8f0; }

.fc-example {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--gray-100);
  font-size: 0.85rem;
  color: var(--gray-500);
  line-height: 1.6;
  font-style: italic;
}

[data-theme="dark"] .fc-example {
  border-top-color: rgba(255,255,255,0.08);
  color: #94a3b8;
}

/* Card animation on change */
.fc-card-wrap.card-exit {
  animation: cardExit 0.2s ease forwards;
}

.fc-card-wrap.card-enter {
  animation: cardEnter 0.3s ease forwards;
}

@keyframes cardExit {
  to { opacity: 0; transform: translateY(-12px) scale(0.97); }
}

@keyframes cardEnter {
  from { opacity: 0; transform: translateY(12px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}

/* ── EMPTY STATE ── */
.fc-empty {
  width: 100%;
  max-width: 640px;
  text-align: center;
  padding: 60px 24px;
  background: var(--white);
  border: 1.5px solid var(--gray-100);
  border-radius: var(--radius-xl);
}

[data-theme="dark"] .fc-empty {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.1);
}

.fc-empty-icon { font-size: 3rem; margin-bottom: 12px; }

.fc-empty h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 8px;
}

.fc-empty p {
  font-size: 0.9rem;
  color: var(--gray-500);
  margin-bottom: 24px;
}

/* ── NAVIGATION ── */
.fc-nav {
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  max-width: 640px;
}

.fc-nav-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1.5px solid var(--gray-200);
  background: var(--white);
  color: var(--gray-600);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition);
  flex-shrink: 0;
}

.fc-nav-btn:hover:not(:disabled) {
  border-color: var(--green-400);
  color: var(--green-700);
  background: var(--green-50);
}

.fc-nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

[data-theme="dark"] .fc-nav-btn {
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.12);
  color: #94a3b8;
}

[data-theme="dark"] .fc-nav-btn:hover:not(:disabled) {
  border-color: var(--green-500);
  color: #4ade80;
  background: rgba(22,163,74,0.12);
}

.fc-action-btns {
  flex: 1;
  display: flex;
  gap: 10px;
}

.fc-action-btn {
  flex: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  border: 1.5px solid;
  font-family: var(--font);
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition);
}

.fc-action-review {
  background: #fffbeb;
  border-color: #fde68a;
  color: #92400e;
}

.fc-action-review:hover {
  background: #fef3c7;
  border-color: #f59e0b;
}

[data-theme="dark"] .fc-action-review {
  background: rgba(245,158,11,0.1);
  border-color: rgba(245,158,11,0.3);
  color: #fbbf24;
}

[data-theme="dark"] .fc-action-review:hover {
  background: rgba(245,158,11,0.18);
}

.fc-action-known {
  background: var(--green-50);
  border-color: var(--green-200);
  color: var(--green-800);
}

.fc-action-known:hover {
  background: var(--green-600);
  border-color: var(--green-600);
  color: white;
}

[data-theme="dark"] .fc-action-known {
  background: rgba(22,163,74,0.1);
  border-color: rgba(22,163,74,0.3);
  color: #4ade80;
}

[data-theme="dark"] .fc-action-known:hover {
  background: var(--green-600);
  border-color: var(--green-600);
  color: white;
}

/* ── SIDE PANEL ── */
.fc-side-panel {
  grid-column: 2;
  grid-row: 2 / 4;
  background: var(--white);
  border: 1.5px solid var(--gray-100);
  border-radius: var(--radius-xl);
  padding: 20px;
  position: sticky;
  top: 88px;
}

[data-theme="dark"] .fc-side-panel {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
}

.fc-side-header {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: var(--gray-500);
  margin-bottom: 14px;
}

.fc-topic-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.fc-topic-row {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.fc-topic-row-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.fc-topic-row-name {
  font-size: 0.8rem;
  font-weight: 500;
  color: #374151;
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

[data-theme="dark"] .fc-topic-row-name { color: #cbd5e1; }

.fc-topic-row-count {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--gray-400);
  white-space: nowrap;
  flex-shrink: 0;
}

.fc-topic-mini-track {
  height: 4px;
  background: var(--gray-100);
  border-radius: 100px;
  overflow: hidden;
}

[data-theme="dark"] .fc-topic-mini-track { background: rgba(255,255,255,0.08); }

.fc-topic-mini-fill {
  height: 100%;
  background: var(--green-500);
  border-radius: 100px;
  transition: width 0.5s ease;
}

/* ── RESPONSIVE ── */
@media (max-width: 900px) {
  .fc-wrap {
    grid-template-columns: 1fr;
  }
  .fc-side-panel {
    grid-column: 1;
    grid-row: auto;
    position: static;
  }
  .fc-progress-wrap { grid-column: 1; }
}

@media (max-width: 600px) {
  .fc-card-wrap { height: 280px; }
  .fc-term { font-size: 1.3rem; }
  .fc-face { padding: 24px 24px; }
  .fc-action-btn span { display: none; }
}