/* ==========================================================================
   Application Custom Layouts & UI Components
   ========================================================================== */

/* Top Subject Filter Bar */
.subject-nav-tabs {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 1200px;
  margin: 0 auto 24px;
  padding: 0 24px;
  overflow-x: auto;
  scrollbar-width: none;
}

.subject-nav-tabs::-webkit-scrollbar {
  display: none;
}

.subject-tab-item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: var(--apple-card-bg);
  border: 1px solid var(--apple-card-border);
  border-radius: var(--apple-radius-pill);
  font-size: 13px;
  font-weight: 500;
  color: var(--apple-text-secondary);
  cursor: pointer;
  white-space: nowrap;
  transition: var(--apple-transition);
}

.subject-tab-item:hover {
  background: var(--apple-bg-secondary);
  color: var(--apple-text-primary);
  border-color: var(--apple-text-secondary);
}

.subject-tab-item.active {
  background: var(--apple-text-primary);
  color: var(--apple-bg);
  border-color: var(--apple-text-primary);
}

/* Chapter Accordion / Selector */
.chapter-selector-box {
  max-width: 1000px;
  margin: 0 auto 24px;
  padding: 0 20px;
}

.chapter-dropdown {
  width: 100%;
  padding: 12px 18px;
  background: var(--apple-card-bg);
  border: 1px solid var(--apple-card-border);
  border-radius: var(--apple-radius-md);
  font-size: 14px;
  font-weight: 500;
  color: var(--apple-text-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  box-shadow: var(--apple-card-shadow);
}

.chapter-list-popover {
  display: none;
  background: var(--apple-card-bg);
  border: 1px solid var(--apple-card-border);
  border-radius: var(--apple-radius-md);
  margin-top: 8px;
  padding: 8px;
  max-height: 280px;
  overflow-y: auto;
  box-shadow: var(--apple-card-hover-shadow);
}

.chapter-list-popover.open {
  display: block;
}

.chapter-item {
  padding: 10px 14px;
  border-radius: var(--apple-radius-sm);
  font-size: 13px;
  color: var(--apple-text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: var(--apple-transition);
}

.chapter-item:hover {
  background: var(--apple-bg-secondary);
  color: var(--apple-blue);
}

.chapter-item.active {
  background: var(--apple-blue-light);
  color: var(--apple-blue);
  font-weight: 600;
}

/* Question Sheet / Answer Grid Modal */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-backdrop.active {
  display: flex;
}

.apple-modal {
  background: var(--apple-card-bg);
  border: 1px solid var(--apple-card-border);
  border-radius: var(--apple-radius-lg);
  width: 100%;
  max-width: 600px;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.25);
  animation: modalPop 0.25s cubic-bezier(0.25, 1, 0.5, 1);
  overflow: hidden;
}

@keyframes modalPop {
  from { opacity: 0; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1); }
}

.modal-header {
  padding: 18px 24px;
  border-bottom: 1px solid var(--apple-card-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 17px;
  font-weight: 600;
}

.modal-close-btn {
  background: none;
  border: none;
  color: var(--apple-text-secondary);
  font-size: 20px;
  cursor: pointer;
}

.modal-body {
  padding: 24px;
  overflow-y: auto;
  flex: 1;
}

.answer-sheet-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(42px, 1fr));
  gap: 10px;
  margin-top: 14px;
}

.sheet-q-btn {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid var(--apple-card-border);
  background: var(--apple-bg-secondary);
  color: var(--apple-text-primary);
  font-size: 13px;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--apple-transition);
}

.sheet-q-btn:hover {
  border-color: var(--apple-blue);
  background: var(--apple-blue-light);
  color: var(--apple-blue);
}

.sheet-q-btn.current {
  border: 2px solid var(--apple-blue);
  font-weight: 700;
}

.sheet-q-btn.answered-correct {
  background: var(--apple-green-light);
  border-color: var(--apple-green);
  color: var(--apple-green);
}

.sheet-q-btn.answered-wrong {
  background: var(--apple-red-light);
  border-color: var(--apple-red);
  color: var(--apple-red);
}

.sheet-q-btn.answered-pending {
  background: var(--apple-blue-light);
  border-color: var(--apple-blue);
  color: var(--apple-blue);
}

/* Spotlight Search Modal */
.spotlight-modal {
  max-width: 680px;
}

.search-input-wrapper {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 20px;
  border-bottom: 1px solid var(--apple-card-border);
}

.search-input-field {
  width: 100%;
  border: none;
  background: transparent;
  font-size: 18px;
  font-weight: 500;
  color: var(--apple-text-primary);
  outline: none;
}

.search-input-field::placeholder {
  color: var(--apple-text-tertiary);
}

.search-results-list {
  max-height: 400px;
  overflow-y: auto;
  padding: 12px;
}

.search-result-item {
  padding: 14px 16px;
  border-radius: var(--apple-radius-md);
  margin-bottom: 6px;
  cursor: pointer;
  transition: var(--apple-transition);
}

.search-result-item:hover {
  background: var(--apple-bg-secondary);
}

.search-item-subject {
  font-size: 11px;
  font-weight: 600;
  color: var(--apple-blue);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.search-item-title {
  font-size: 14px;
  font-weight: 500;
  color: var(--apple-text-primary);
  line-height: 1.4;
  margin-bottom: 4px;
}

.search-item-snippet {
  font-size: 12px;
  color: var(--apple-text-secondary);
}

/* Exam Mode Banner & Timer */
.exam-header-banner {
  display: none;
  align-items: center;
  justify-content: space-between;
  background: linear-gradient(135deg, #0071e3 0%, #1d1d1f 100%);
  color: #ffffff;
  padding: 16px 24px;
  border-radius: var(--apple-radius-lg);
  margin-bottom: 20px;
}

.exam-header-banner.active {
  display: flex;
}

.exam-timer-display {
  font-family: var(--apple-font-mono);
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 0.05em;
  background: rgba(255, 255, 255, 0.15);
  padding: 4px 14px;
  border-radius: var(--apple-radius-pill);
}

/* Score Summary Card */
.score-card {
  text-align: center;
  padding: 36px 20px;
}

.score-circle-value {
  font-size: 56px;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  margin-bottom: 8px;
}

.score-pass {
  color: var(--apple-green);
}

.score-fail {
  color: var(--apple-red);
}

/* Footer & Copyright */
.apple-footer {
  margin-top: auto;
  background: var(--apple-bg-secondary);
  border-top: 1px solid var(--apple-card-border);
  padding: 32px 24px 48px;
  font-size: 12px;
  color: var(--apple-text-secondary);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--apple-text-secondary);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--apple-text-primary);
  text-decoration: underline;
}