/* ===== ASSIGNMENT STUDY PAGE ===== */

/* Loading & Error */
.as-loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: #0f0f14;
  color: #e5e7eb;
  gap: 12px;
}
.as-spinner {
  width: 28px;
  height: 28px;
  border: 3px solid #2a2a3a;
  border-top-color: #6366F1;
  border-radius: 50%;
  animation: as-spin 0.7s linear infinite;
}
@keyframes as-spin { to { transform: rotate(360deg); } }
.as-error-icon { font-size: 48px; margin-bottom: 8px; }

/* Container */
.as-container {
  min-height: 100vh;
  background: #0f0f14;
  color: #e5e7eb;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  display: flex;
  flex-direction: column;
}

/* Back link */
.as-back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: #6366F1;
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 24px;
}
.as-back-link:hover { color: #818cf8; }

/* ===== READY SCREEN ===== */
.as-ready {
  max-width: 500px;
  margin: 0 auto;
  padding: 40px 20px;
  width: 100%;
}
.as-ready-card {
  background: #16161e;
  border: 1px solid #2a2a3a;
  border-radius: 20px;
  padding: 32px 24px;
  text-align: center;
}
.as-ready-icon { font-size: 56px; margin-bottom: 16px; }
.as-ready-card h1 {
  font-size: 24px;
  font-weight: 800;
  margin: 0 0 12px;
  color: #f1f5f9;
}
.as-ready-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 20px;
  font-size: 13px;
}
.as-deadline {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: #f59e0b;
}
.as-xp-badge {
  background: rgba(99, 102, 241, 0.15);
  color: #818cf8;
  padding: 4px 10px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 13px;
}

.as-ready-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 20px;
}
.as-ready-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.as-ready-stat-val {
  font-size: 32px;
  font-weight: 800;
  color: #6366F1;
}
.as-ready-stat-label {
  font-size: 12px;
  color: #64748b;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.as-deck-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: 20px;
}
.as-deck-chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: #1e1e2e;
  border: 1px solid #2a2a3a;
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 13px;
  color: #94a3b8;
}

.as-ready-info {
  background: #1a1a26;
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 24px;
  font-size: 13px;
  color: #94a3b8;
  line-height: 1.5;
}
.as-rating-legend {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 12px;
  flex-wrap: wrap;
}
.as-legend-item {
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
}
.as-legend-item.again { background: rgba(239,68,68,0.15); color: #f87171; }
.as-legend-item.hard { background: rgba(245,158,11,0.15); color: #fbbf24; }
.as-legend-item.good { background: rgba(16,185,129,0.15); color: #34d399; }
.as-legend-item.easy { background: rgba(99,102,241,0.15); color: #818cf8; }

/* Buttons */
.as-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s;
}
.as-btn-primary {
  background: #6366F1;
  color: #fff;
}
.as-btn-primary:hover { background: #5558e6; }
.as-btn-secondary {
  background: #1e1e2e;
  color: #e5e7eb;
  border: 1px solid #2a2a3a;
}
.as-btn-secondary:hover { background: #252535; }
.as-btn-start {
  background: linear-gradient(135deg, #6366F1, #8B5CF6);
  color: #fff;
  width: 100%;
  padding: 16px;
  font-size: 17px;
  border-radius: 14px;
}
.as-btn-start:hover { transform: translateY(-1px); box-shadow: 0 4px 16px rgba(99,102,241,0.3); }

/* ===== STUDY SESSION ===== */

/* Header */
.as-study-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: #16161e;
  border-bottom: 1px solid #2a2a3a;
  position: sticky;
  top: 0;
  z-index: 10;
}
.as-close-btn {
  color: #94a3b8;
  font-size: 24px;
  text-decoration: none;
  display: flex;
  align-items: center;
}
.as-close-btn:hover { color: #f1f5f9; }
.as-study-title {
  font-size: 15px;
  font-weight: 700;
  color: #f1f5f9;
  text-align: center;
  flex: 1;
}
.as-study-counter {
  font-size: 13px;
  color: #64748b;
  font-weight: 600;
  min-width: 50px;
  text-align: right;
}
.as-study-header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}
.as-btn-finish {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  background: rgba(239, 68, 68, 0.1);
  color: #EF4444;
  border: 1px solid rgba(239, 68, 68, 0.3);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.as-btn-finish:hover {
  background: rgba(239, 68, 68, 0.2);
  border-color: #EF4444;
}
.as-btn-finish ion-icon {
  font-size: 16px;
}

/* Progress bar */
.as-progress-bar {
  height: 4px;
  background: #1e1e2e;
  overflow: hidden;
}
.as-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #6366F1, #8B5CF6);
  transition: width 0.3s ease;
  border-radius: 0 2px 2px 0;
}

/* Card area */
.as-card-area {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  perspective: 1000px;
}

/* Flashcard */
.as-flashcard {
  width: 100%;
  max-width: 480px;
  min-height: 280px;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}
.as-flashcard-inner {
  position: relative;
  width: 100%;
  min-height: 280px;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
}
.as-flashcard.flipped .as-flashcard-inner {
  transform: rotateY(180deg);
}
.as-flashcard-front,
.as-flashcard-back {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: 20px;
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}
.as-flashcard-front {
  background: linear-gradient(145deg, #1e1e2e, #16161e);
  border: 2px solid #2a2a3a;
}
.as-flashcard-back {
  background: linear-gradient(145deg, #1a1a3a, #1e1e2e);
  border: 2px solid #6366F1;
  transform: rotateY(180deg);
}

.as-card-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: #64748b;
  margin-bottom: 16px;
  font-weight: 600;
}
.as-card-text {
  font-size: 24px;
  font-weight: 700;
  color: #f1f5f9;
  line-height: 1.4;
  word-break: break-word;
}
.as-tap-hint {
  position: absolute;
  bottom: 16px;
  font-size: 12px;
  color: #4b5563;
  animation: as-pulse 2s infinite;
}
@keyframes as-pulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

/* Actions */
.as-actions {
  padding: 16px 20px 32px;
  display: flex;
  justify-content: center;
}
.as-btn-show {
  background: #6366F1;
  color: #fff;
  padding: 14px 32px;
  border-radius: 14px;
  font-size: 16px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  max-width: 480px;
  justify-content: center;
}
.as-btn-show kbd {
  background: rgba(255,255,255,0.15);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 12px;
}
.as-btn-show:hover { background: #5558e6; }

/* Rating buttons */
.as-rating-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  width: 100%;
  max-width: 480px;
}
.as-rate-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 14px 8px;
  border-radius: 14px;
  border: 2px solid transparent;
  cursor: pointer;
  font-size: 13px;
  font-weight: 700;
  transition: all 0.15s;
}
.as-rate-btn ion-icon { font-size: 22px; }
.as-rate-btn kbd {
  font-size: 10px;
  opacity: 0.5;
  background: rgba(255,255,255,0.1);
  padding: 1px 6px;
  border-radius: 3px;
}
.as-rate-again {
  background: rgba(239,68,68,0.1);
  color: #f87171;
  border-color: rgba(239,68,68,0.2);
}
.as-rate-again:hover { background: rgba(239,68,68,0.2); }
.as-rate-hard {
  background: rgba(245,158,11,0.1);
  color: #fbbf24;
  border-color: rgba(245,158,11,0.2);
}
.as-rate-hard:hover { background: rgba(245,158,11,0.2); }
.as-rate-good {
  background: rgba(16,185,129,0.1);
  color: #34d399;
  border-color: rgba(16,185,129,0.2);
}
.as-rate-good:hover { background: rgba(16,185,129,0.2); }
.as-rate-easy {
  background: rgba(99,102,241,0.1);
  color: #818cf8;
  border-color: rgba(99,102,241,0.2);
}
.as-rate-easy:hover { background: rgba(99,102,241,0.2); }

/* ===== SUMMARY ===== */
.as-summary {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.as-summary-card {
  background: #16161e;
  border: 1px solid #2a2a3a;
  border-radius: 20px;
  padding: 32px 24px;
  text-align: center;
  max-width: 440px;
  width: 100%;
}
.as-summary-icon { font-size: 56px; margin-bottom: 12px; }
.as-summary-card h1 {
  font-size: 24px;
  font-weight: 800;
  margin: 0 0 4px;
  color: #f1f5f9;
}
.as-summary-subtitle {
  color: #64748b;
  font-size: 14px;
  margin: 0 0 24px;
}

/* Accuracy ring */
.as-accuracy-ring {
  position: relative;
  width: 120px;
  height: 120px;
  margin: 0 auto 24px;
}
.as-ring-svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}
.as-ring-bg {
  fill: none;
  stroke: #2a2a3a;
  stroke-width: 3;
}
.as-ring-fill {
  fill: none;
  stroke: #6366F1;
  stroke-width: 3;
  stroke-linecap: round;
  transition: stroke-dasharray 1s ease;
}
.as-accuracy-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 28px;
  font-weight: 800;
  color: #f1f5f9;
}

/* Summary stats */
.as-summary-stats {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 24px;
}
.as-sum-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.as-sum-val {
  font-size: 20px;
  font-weight: 800;
  color: #f1f5f9;
}
.as-sum-label {
  font-size: 11px;
  color: #64748b;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Rating breakdown */
.as-rating-breakdown {
  margin-bottom: 24px;
}
.as-rb-item {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}
.as-rb-label {
  width: 50px;
  text-align: right;
  font-size: 12px;
  font-weight: 600;
}
.as-rb-bar {
  flex: 1;
  height: 10px;
  background: #1a1a26;
  border-radius: 5px;
  overflow: hidden;
}
.as-rb-bar div {
  height: 100%;
  border-radius: 5px;
  transition: width 0.5s ease;
  min-width: 2px;
}
.as-rb-item.again .as-rb-label { color: #f87171; }
.as-rb-item.again .as-rb-bar div { background: #ef4444; }
.as-rb-item.hard .as-rb-label { color: #fbbf24; }
.as-rb-item.hard .as-rb-bar div { background: #f59e0b; }
.as-rb-item.good .as-rb-label { color: #34d399; }
.as-rb-item.good .as-rb-bar div { background: #10b981; }
.as-rb-item.easy .as-rb-label { color: #818cf8; }
.as-rb-item.easy .as-rb-bar div { background: #6366f1; }
.as-rb-val {
  width: 24px;
  text-align: left;
  font-size: 13px;
  font-weight: 700;
  color: #94a3b8;
}

/* XP earned */
.as-xp-earned {
  background: rgba(99, 102, 241, 0.12);
  color: #818cf8;
  padding: 12px 20px;
  border-radius: 12px;
  font-size: 18px;
  font-weight: 800;
  margin-bottom: 20px;
}

.as-saving {
  font-size: 12px;
  color: #64748b;
  margin-bottom: 12px;
}

.as-summary-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.as-summary-actions .as-btn {
  width: 100%;
}

/* ===== Complete Assignment Section ===== */
.as-complete-section {
  margin: 20px 0;
  padding: 20px;
  background: linear-gradient(135deg, rgba(16,185,129,0.08), rgba(16,185,129,0.02));
  border: 1px solid rgba(16,185,129,0.2);
  border-radius: 12px;
  text-align: center;
}
.as-complete-hint {
  font-size: 13px;
  color: #94a3b8;
  margin-bottom: 14px;
  line-height: 1.5;
}
.as-btn-complete {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: linear-gradient(135deg, #10B981, #059669);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 4px 16px rgba(16,185,129,0.3);
}
.as-btn-complete:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(16,185,129,0.4);
}
.as-btn-complete:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}
.as-btn-spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: as-spin 0.6s linear infinite;
}
@keyframes as-spin {
  to { transform: rotate(360deg); }
}
.as-complete-success {
  margin: 20px 0;
  padding: 24px;
  background: linear-gradient(135deg, rgba(16,185,129,0.12), rgba(16,185,129,0.04));
  border: 1px solid rgba(16,185,129,0.3);
  border-radius: 12px;
  text-align: center;
  animation: as-fadeIn 0.5s ease;
}
@keyframes as-fadeIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
.as-complete-check {
  font-size: 48px;
  margin-bottom: 8px;
}
.as-complete-success h3 {
  font-size: 18px;
  color: #10B981;
  margin-bottom: 4px;
}
.as-xp-awarded {
  font-size: 20px;
  font-weight: 800;
  background: linear-gradient(135deg, #F59E0B, #EAB308);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Light theme for complete section */
[data-theme="light"] .as-complete-section {
  background: linear-gradient(135deg, rgba(16,185,129,0.06), rgba(16,185,129,0.02));
}
[data-theme="light"] .as-complete-hint { color: #6b7280; }
[data-theme="light"] .as-complete-success {
  background: linear-gradient(135deg, rgba(16,185,129,0.08), rgba(16,185,129,0.02));
}

/* ===== LIGHT THEME ===== */
[data-theme="light"] .as-container,
[data-theme="light"] .as-loading {
  background: #f8f9fb;
  color: #1e293b;
}
[data-theme="light"] .as-ready-card,
[data-theme="light"] .as-summary-card {
  background: #fff;
  border-color: #e5e7eb;
}
[data-theme="light"] .as-study-header {
  background: #fff;
  border-color: #e5e7eb;
}
[data-theme="light"] .as-flashcard-front {
  background: linear-gradient(145deg, #fff, #f8f9fb);
  border-color: #e5e7eb;
}
[data-theme="light"] .as-flashcard-back {
  background: linear-gradient(145deg, #f0f0ff, #fff);
  border-color: #6366F1;
}
[data-theme="light"] .as-card-text { color: #1e293b; }
[data-theme="light"] .as-card-label { color: #94a3b8; }
[data-theme="light"] .as-progress-bar { background: #e5e7eb; }
[data-theme="light"] .as-deck-chip {
  background: #f3f4f6;
  border-color: #e5e7eb;
  color: #374151;
}
[data-theme="light"] .as-ready-info {
  background: #f3f4f6;
  color: #4b5563;
}
[data-theme="light"] .as-btn-secondary {
  background: #f3f4f6;
  color: #1e293b;
  border-color: #e5e7eb;
}
[data-theme="light"] .as-ring-bg { stroke: #e5e7eb; }
[data-theme="light"] .as-rb-bar { background: #f3f4f6; }
[data-theme="light"] .as-summary-card h1,
[data-theme="light"] .as-ready-card h1,
[data-theme="light"] .as-accuracy-text,
[data-theme="light"] .as-sum-val { color: #1e293b; }

/* ===== MOBILE ===== */
@media (max-width: 480px) {
  .as-flashcard { min-height: 240px; }
  .as-flashcard-inner { min-height: 240px; }
  .as-flashcard-front, .as-flashcard-back { padding: 24px 16px; }
  .as-card-text { font-size: 20px; }
  .as-rating-buttons { gap: 6px; }
  .as-rate-btn { padding: 10px 4px; font-size: 11px; }
  .as-rate-btn ion-icon { font-size: 18px; }
  .as-ready-card { padding: 24px 16px; }
  .as-ready-card h1 { font-size: 20px; }
  .as-ready-stat-val { font-size: 28px; }
  .as-summary-card { padding: 24px 16px; }
  .as-btn-finish { padding: 5px 10px; font-size: 12px; }
  .as-btn-finish span { display: none; }
  .as-study-title { font-size: 13px; }
}

/* ===== XP Formula ===== */
.as-xp-formula { background: var(--card-bg, #1e1e2e); border: 1px solid var(--border, #333); border-radius: 12px; padding: 16px; margin-top: 12px; }
.as-xp-formula h4 { font-size: 14px; font-weight: 600; color: var(--text-secondary, #aaa); margin: 0 0 10px; }
.as-xp-formula p { font-size: 13px; color: var(--text-secondary, #aaa); margin: 4px 0; display: flex; justify-content: space-between; }
.as-xp-formula p strong { color: var(--text, #fff); }
.as-xp-formula hr { border: none; border-top: 1px solid var(--border, #333); margin: 8px 0; }
.as-xp-formula .xp-total { font-size: 18px; font-weight: 700; color: #F59E0B; }