/**
 * ExamHub — Exam Engine Styles
 * Full-page distraction-free exam UI.
 */

/* ─── App Shell ────────────────────────────────────────────────────────────── */
.eh-exam-app {
  display: flex;
  flex-direction: column;
  height: 100dvh;
  height: 100vh;
  overflow: hidden;
  background: var(--eh-bg-primary);
  position: relative;
}

/* ─── Header ────────────────────────────────────────────────────────────────── */
.eh-exam-header {
  background: var(--eh-bg-secondary);
  border-bottom: 1px solid var(--eh-border);
  flex-shrink: 0;
  z-index: 100;
}
.eh-exam-header-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  max-width: 900px;
  margin: 0 auto;
  width: 100%;
}
.eh-exam-title-block {
  flex: 1;
  text-align: center;
}
.eh-exam-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--eh-text-primary);
  margin: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 280px;
}
.eh-exam-progress-text {
  font-size: 0.8rem;
  color: var(--eh-text-muted);
  margin-top: 0.1rem;
}
.eh-exam-timer-block {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  background: var(--eh-bg-tertiary);
  border: 1px solid var(--eh-border);
  border-radius: 20px;
  padding: 0.35rem 0.85rem;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--eh-text-primary);
  flex-shrink: 0;
  min-width: 80px;
  justify-content: center;
}
.eh-exam-timer-block.warning {
  background: var(--eh-warning-bg);
  border-color: rgba(245,158,11,.4);
  color: var(--eh-warning);
  animation: pulse-warn 1s infinite;
}
.eh-exam-timer-block.danger {
  background: var(--eh-danger-bg);
  border-color: rgba(239,68,68,.4);
  color: var(--eh-danger);
  animation: pulse-warn 0.5s infinite;
}
@keyframes pulse-warn {
  0%,100% { opacity: 1; }
  50%      { opacity: 0.7; }
}

/* Progress bar track */
.eh-exam-progress-bar-track {
  height: 3px;
  background: var(--eh-bg-tertiary);
}
.eh-exam-progress-bar-fill {
  height: 100%;
  background: var(--eh-accent);
  transition: width 0.4s ease;
}

/* ─── Main Content ────────────────────────────────────────────────────────── */
.eh-exam-main {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem 1rem;
}
.eh-exam-main > * {
  max-width: 800px;
  margin: 0 auto;
}

/* Loading */
.eh-exam-loading-screen {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 300px;
}
.eh-loading-spinner {
  width: 44px; height: 44px;
  border: 3px solid var(--eh-border);
  border-top-color: var(--eh-accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

/* ─── Question ────────────────────────────────────────────────────────────── */
.eh-question-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}
.eh-review-btn {
  margin-right: auto !important;
  margin-left: auto !important;
}
[dir="rtl"] .eh-review-btn { margin-right: auto; margin-left: 0; }
.eh-review-btn.active { color: var(--eh-review-color) !important; border-color: var(--eh-review-color) !important; }

.eh-question-body {
  margin-bottom: 1.5rem;
}
.eh-question-text {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--eh-text-primary);
  font-weight: 500;
  user-select: none;
  -webkit-user-select: none;
}
.exam-subject-ltr .eh-question-text,
.exam-subject-ltr .eh-question-body-content,
.exam-subject-ltr .eh-fill-blank-wrapper,
.exam-subject-ltr .eh-essay-textarea {
  direction: ltr;
  text-align: left;
}
.eh-question-body-content {
  margin-top: 0.9rem;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--eh-text-secondary);
}
.eh-question-body-content p:last-child {
  margin-bottom: 0;
}
.eh-question-body-content img {
  max-width: 100%;
  height: auto;
  border-radius: var(--eh-radius);
}
.eh-question-image {
  max-width: 100%;
  border-radius: var(--eh-radius);
  margin-top: 1rem;
  border: 1px solid var(--eh-border);
  user-select: none;
  -webkit-user-select: none;
  -webkit-user-drag: none;
}
.eh-question-math {
  font-size: 1.2rem;
  color: var(--eh-text-primary);
  margin-top: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--eh-bg-tertiary);
  border-radius: var(--eh-radius);
  border: 1px solid var(--eh-border);
  overflow-x: auto;
  user-select: none;
  -webkit-user-select: none;
}

/* Per-question timer */
.eh-question-timer {
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.eh-qtimer-bar-track {
  flex: 1;
  height: 6px;
  background: var(--eh-bg-tertiary);
  border-radius: 3px;
}
.eh-qtimer-bar-fill {
  height: 100%;
  background: var(--eh-accent);
  border-radius: 3px;
  transition: width 1s linear;
}
.eh-qtimer-bar-fill.low  { background: var(--eh-warning); }
.eh-qtimer-bar-fill.critical { background: var(--eh-danger); }
.eh-qtimer-text {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--eh-text-secondary);
  min-width: 24px;
  text-align: center;
}

/* ─── Answer Area ────────────────────────────────────────────────────────── */
.eh-answer-area {
  margin-bottom: 1rem;
}

/* MCQ / Correct answer options */
.eh-answer-option {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding: 0.875rem 1.1rem;
  background: var(--eh-bg-card);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius);
  cursor: pointer;
  transition: var(--eh-transition);
  margin-bottom: 0.625rem;
  text-align: right;
  width: 100%;
  color: var(--eh-text-primary);
  font-size: 1rem;
  line-height: 1.5;
  user-select: none;
  -webkit-user-select: none;
}
.exam-subject-ltr .eh-answer-option {
  text-align: left;
}
.eh-answer-option:hover {
  border-color: var(--eh-accent);
  background: var(--eh-accent-light);
}
.eh-answer-option.selected {
  border-color: var(--eh-accent);
  background: var(--eh-selected-bg);
}
.eh-answer-option .option-letter {
  width: 30px; height: 30px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: var(--eh-bg-tertiary);
  border: 1px solid var(--eh-border);
  font-size: 0.82rem;
  font-weight: 700;
  flex-shrink: 0;
  color: var(--eh-text-secondary);
}
.eh-answer-option.selected .option-letter {
  background: var(--eh-accent);
  color: #fff;
  border-color: var(--eh-accent);
}
.exam-subject-ltr .eh-answer-option img {
  margin-right: 0 !important;
  margin-left: auto;
}
/* After submit: correct / wrong */
.eh-answer-option.correct {
  border-color: var(--eh-success);
  background: var(--eh-correct-bg);
}
.eh-answer-option.wrong {
  border-color: var(--eh-danger);
  background: var(--eh-wrong-bg);
}
.eh-answer-option.correct .option-letter { background: var(--eh-success); color: #fff; }
.eh-answer-option.wrong .option-letter   { background: var(--eh-danger); color: #fff; }

/* True/False */
.eh-tf-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.875rem;
}
.eh-tf-btn {
  padding: 1.5rem 1rem;
  border-radius: var(--eh-radius-lg);
  font-size: 1.1rem;
  font-weight: 700;
  border: 2px solid var(--eh-border);
  background: var(--eh-bg-card);
  color: var(--eh-text-primary);
  cursor: pointer;
  transition: var(--eh-transition);
  text-align: center;
  user-select: none;
  -webkit-user-select: none;
}
.eh-tf-btn:hover { border-color: var(--eh-accent); background: var(--eh-accent-light); }
.eh-tf-btn.selected.true-btn { border-color: var(--eh-success); background: var(--eh-correct-bg); color: var(--eh-success); }
.eh-tf-btn.selected.false-btn { border-color: var(--eh-danger); background: var(--eh-wrong-bg); color: var(--eh-danger); }

/* Fill in blank */
.eh-fill-blank-input {
  display: inline-block;
  width: 140px;
  background: var(--eh-bg-input);
  border: 2px solid var(--eh-accent);
  border-radius: var(--eh-radius-sm);
  padding: 0.3rem 0.6rem;
  color: var(--eh-text-primary);
  font-family: var(--eh-font);
  font-size: 1rem;
  text-align: center;
}
.eh-fill-blank-input:focus { outline: none; box-shadow: 0 0 0 3px var(--eh-accent-light); }
.eh-fill-blank-wrapper {
  font-size: 1.05rem;
  line-height: 2.4;
  color: var(--eh-text-primary);
}

/* Matching */
.eh-matching-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 0.75rem 0.5rem;
  align-items: center;
}
.eh-match-left {
  background: var(--eh-bg-card);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius);
  padding: 0.75rem 1rem;
  font-weight: 600;
  text-align: center;
  user-select: none;
  -webkit-user-select: none;
}
.eh-match-right select {
  background: var(--eh-bg-input);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius);
  color: var(--eh-text-primary);
  padding: 0.55rem 0.75rem;
  font-family: var(--eh-font);
  width: 100%;
}
.eh-match-arrow { color: var(--eh-text-muted); text-align: center; font-size: 1rem; }

/* Ordering */
.eh-ordering-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.eh-ordering-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1.1rem;
  background: var(--eh-bg-card);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius);
  margin-bottom: 0.625rem;
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
  transition: var(--eh-transition);
}
.eh-ordering-item:active { cursor: grabbing; }
.eh-ordering-item.sortable-ghost {
  opacity: 0.4;
  background: var(--eh-accent-light);
  border-color: var(--eh-accent);
}
.eh-ordering-item .drag-handle {
  color: var(--eh-text-muted);
  font-size: 1.1rem;
  flex-shrink: 0;
}
.eh-ordering-text {
  flex: 1;
}
.eh-ordering-actions {
  display: flex;
  gap: 0.35rem;
  margin-inline-start: auto;
}
.eh-ordering-move {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  border: 1px solid var(--eh-border);
  background: var(--eh-bg-secondary);
  color: var(--eh-text-secondary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--eh-transition);
}
.eh-ordering-move:hover {
  border-color: var(--eh-accent);
  color: var(--eh-accent);
}
.eh-ordering-num {
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--eh-bg-tertiary);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.8rem; font-weight: 700;
  color: var(--eh-text-muted);
  flex-shrink: 0;
}

/* Essay */
.eh-essay-textarea {
  width: 100%;
  min-height: 180px;
  background: var(--eh-bg-input);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius);
  color: var(--eh-text-primary);
  font-family: var(--eh-font);
  font-size: 1rem;
  padding: 1rem;
  resize: vertical;
  transition: var(--eh-transition);
}
.eh-essay-textarea:focus {
  border-color: var(--eh-border-focus);
  box-shadow: 0 0 0 3px var(--eh-accent-light);
  outline: none;
}
.eh-essay-word-count { font-size: 0.78rem; color: var(--eh-text-muted); margin-top: 0.4rem; text-align: left; }
.exam-subject-ltr .eh-question-meta,
.exam-subject-ltr .eh-question-timer,
.exam-subject-ltr .eh-q-nav-header,
.exam-subject-ltr .eh-q-nav-legend,
.exam-subject-ltr .eh-q-dots {
  direction: ltr;
}

/* ─── Explanation (post-submit) ──────────────────────────────────────────── */
.eh-explanation-block {
  margin-top: 1.25rem;
  background: rgba(67, 97, 238, .08);
  border: 1px solid var(--eh-accent-glow);
  border-radius: var(--eh-radius);
  padding: 1rem 1.25rem;
}
.eh-explanation-label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--eh-accent);
  display: flex; align-items: center; gap: 0.35rem;
  margin-bottom: 0.5rem;
}
.eh-explanation-text {
  color: var(--eh-text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Result share CTA */
.eh-facebook-share-btn {
  position: relative;
  isolation: isolate;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.7rem;
  min-height: 50px;
  padding: 0.55rem 1rem 0.55rem 1.15rem;
  overflow: hidden;
  color: #fff;
  border: 1px solid rgba(91, 141, 255, 0.7);
  background:
    radial-gradient(circle at 18% 20%, rgba(255,255,255,0.34), transparent 24%),
    linear-gradient(135deg, #1877f2 0%, #2457d6 54%, #142b78 100%);
  box-shadow: 0 12px 30px rgba(24, 119, 242, 0.3), inset 0 1px 0 rgba(255,255,255,0.22);
}
.eh-facebook-share-btn::before {
  content: '';
  position: absolute;
  inset: -45% -18%;
  z-index: -1;
  background: linear-gradient(100deg, transparent 34%, rgba(255,255,255,0.36) 50%, transparent 66%);
  transform: translateX(60%) rotate(8deg);
  transition: transform 0.55s ease;
}
.eh-facebook-share-btn:hover,
.eh-facebook-share-btn:focus {
  color: #fff;
  border-color: rgba(169, 199, 255, 0.95);
  transform: translateY(-2px);
  box-shadow: 0 16px 34px rgba(24, 119, 242, 0.42), 0 0 0 3px rgba(24, 119, 242, 0.14);
}
.eh-facebook-share-btn:hover::before,
.eh-facebook-share-btn:focus::before {
  transform: translateX(-62%) rotate(8deg);
}
.eh-facebook-share-icon {
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  border-radius: 50%;
  background: rgba(255,255,255,0.18);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.2);
  font-size: 1.15rem;
}
.eh-facebook-share-copy {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.05rem;
  line-height: 1.2;
  text-align: start;
}
[dir="rtl"] .eh-facebook-share-copy {
  align-items: flex-end;
}
.eh-facebook-share-copy strong {
  font-size: 0.95rem;
  font-weight: 800;
}
.eh-facebook-share-copy small {
  color: rgba(255,255,255,0.78);
  font-size: 0.72rem;
  font-weight: 600;
}
.eh-facebook-share-spark {
  color: #ffe082;
  font-size: 0.95rem;
  filter: drop-shadow(0 0 6px rgba(255,224,130,0.55));
}

/* ─── Footer ─────────────────────────────────────────────────────────────── */
.eh-exam-footer {
  background: var(--eh-bg-secondary);
  border-top: 1px solid var(--eh-border);
  flex-shrink: 0;
  padding: 0.75rem 1rem;
  padding-bottom: calc(0.75rem + env(safe-area-inset-bottom));
}
.eh-exam-footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  max-width: 900px;
  margin: 0 auto;
}

/* ─── Question Navigator ─────────────────────────────────────────────────── */
.eh-q-navigator {
  position: fixed;
  bottom: 70px;
  right: 1rem;
  left: 1rem;
  max-width: 500px;
  margin: 0 auto;
  background: var(--eh-bg-card);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius-lg);
  box-shadow: var(--eh-shadow-lg);
  z-index: 200;
  padding: 1rem;
}
.eh-q-nav-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
  font-weight: 600;
  font-size: 0.9rem;
}
.eh-q-nav-legend {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.78rem;
  color: var(--eh-text-muted);
  margin-bottom: 0.75rem;
}
.eh-dot {
  width: 12px; height: 12px;
  border-radius: 50%;
  display: inline-block;
}
.eh-dot.answered  { background: var(--eh-success); }
.eh-dot.current   { background: var(--eh-accent); }
.eh-dot.review    { background: var(--eh-review-color); }
.eh-dot.unanswered { background: var(--eh-bg-tertiary); border: 1px solid var(--eh-border); }
.eh-q-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.eh-q-dot {
  width: 34px; height: 34px;
  border-radius: var(--eh-radius-sm);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.78rem; font-weight: 700;
  cursor: pointer;
  transition: var(--eh-transition);
  border: 1px solid var(--eh-border);
  background: var(--eh-bg-tertiary);
  color: var(--eh-text-muted);
}
.eh-q-dot:hover    { border-color: var(--eh-accent); color: var(--eh-accent); }
.eh-q-dot.answered { background: var(--eh-success-bg); border-color: var(--eh-success); color: var(--eh-success); }
.eh-q-dot.current  { background: var(--eh-accent); border-color: var(--eh-accent); color: #fff; }
.eh-q-dot.review   { background: var(--eh-warning-bg); border-color: var(--eh-review-color); color: var(--eh-review-color); }

/* ─── Autosave Indicator ─────────────────────────────────────────────────── */
.eh-autosave-indicator {
  position: fixed;
  top: 70px;
  right: 1rem;
  background: var(--eh-success-bg);
  border: 1px solid rgba(34,197,94,.3);
  color: var(--eh-success);
  border-radius: 20px;
  padding: 0.3rem 0.85rem;
  font-size: 0.78rem;
  font-weight: 600;
  z-index: 1000;
  pointer-events: none;
  animation: fadeIn .3s ease;
}

/* ─── Modals ─────────────────────────────────────────────────────────────── */
.eh-modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.75);
  backdrop-filter: blur(4px);
  z-index: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}
.eh-modal-box {
  background: var(--eh-bg-card);
  border: 1px solid var(--eh-border);
  border-radius: var(--eh-radius-xl);
  padding: 2rem;
  max-width: 440px;
  width: 100%;
  text-align: center;
  animation: slideUp .25s ease;
}
.eh-modal-icon { margin-bottom: 1rem; }
@keyframes slideUp {
  from { transform: translateY(20px); opacity: 0; }
  to   { transform: translateY(0);    opacity: 1; }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* ─── Mobile Adjustments ─────────────────────────────────────────────────── */
@media (max-width: 576px) {
  .eh-exam-name { max-width: 160px; font-size: 0.85rem; }
  .eh-exam-main { padding: 1rem 0.875rem; }
  .eh-question-text { font-size: 1rem; }
  .eh-answer-option { padding: 0.75rem 0.875rem; font-size: 0.95rem; }
  .eh-tf-options { grid-template-columns: 1fr; gap: 0.5rem; }
  .eh-tf-btn { padding: 1rem; }
  .eh-matching-grid { grid-template-columns: 1fr; }
  .eh-match-arrow { display: none; }
  .eh-q-navigator { bottom: 75px; }
  .eh-facebook-share-btn {
    width: 100%;
    max-width: 320px;
  }
}