/* ============================================================
   KTPL Exercise Builder — Light Theme
   Scoped under .exercise-page to avoid conflicts
   ============================================================ */

/* --- Variables --- */
.exercise-page {
  --ex-text: #0f172a;
  --ex-muted: #64748b;
  --ex-accent: #0ea5e9;
  --ex-success: #16a34a;
  --ex-danger: #dc2626;
  --ex-border: rgba(15, 23, 42, 0.08);
  --ex-border-strong: rgba(15, 23, 42, 0.15);
  --ex-surface: #ffffff;
  --ex-bg-tint: rgba(224, 242, 254, 0.5);
  --ex-shadow: 0 20px 45px rgba(15, 23, 42, 0.06);
  --ex-radius-panel: 26px;
  --ex-radius-card: 22px;
  --ex-radius-input: 16px;
  --ex-radius-pill: 999px;
}

/* --- Page body --- */
body.exercise-page {
  background: linear-gradient(135deg, #f0f9ff, #e0f2fe);
  color: var(--ex-text);
  min-height: 100vh;
}

/* --- Main container --- */
.exercise-shell {
  max-width: 900px;
  margin: 60px auto 120px;
  padding: 0 24px;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

/* ============================================================
   Step sections
   ============================================================ */
.exercise-step {
  background: var(--ex-surface);
  border: 1px solid var(--ex-border);
  border-radius: var(--ex-radius-panel);
  padding: 28px;
  box-shadow: var(--ex-shadow);
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.step-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.step-eyebrow {
  font-size: 0.8rem;
  color: var(--ex-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 4px;
}

.step-title {
  margin: 0;
  font-size: 1.5rem;
  color: var(--ex-text);
  line-height: 1.3;
}

.step-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border-radius: var(--ex-radius-pill);
  padding: 6px 14px;
  border: 1px solid rgba(14, 165, 233, 0.3);
  background: var(--ex-bg-tint);
  color: var(--ex-accent);
  font-size: 0.85rem;
  white-space: nowrap;
  flex-shrink: 0;
}

/* ============================================================
   Section titles & badges (from JS)
   ============================================================ */
.ex-section-title {
  margin: 8px 0 4px;
  font-size: 1.15rem;
  color: var(--ex-accent);
}

.ex-difficulty-badge {
  display: inline-block;
  border-radius: var(--ex-radius-pill);
  padding: 3px 10px;
  background: var(--ex-bg-tint);
  color: var(--ex-accent);
  font-size: 0.78rem;
  font-weight: 600;
}

.ex-radio-label {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
  cursor: pointer;
}

.ex-radio-label strong {
  font-size: 0.95rem;
  min-width: 18px;
}

.ex-btn-danger {
  border-color: rgba(220, 38, 38, 0.3) !important;
  color: var(--ex-danger) !important;
}

.ex-btn-danger:hover {
  background: rgba(220, 38, 38, 0.06) !important;
  border-color: var(--ex-danger) !important;
}

.ex-field {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.95rem;
}

.ex-field span {
  color: var(--ex-muted);
  font-size: 0.9rem;
}

.ex-field--full {
  grid-column: 1 / -1;
}

.ex-form-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 6px;
}

/* Preview rendered from JS */
.preview-header {
  text-align: center;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--ex-border);
}

.preview-header h3 {
  margin: 0 0 4px;
  font-size: 1.3rem;
  color: var(--ex-text);
}

.preview-header p {
  margin: 0;
  color: var(--ex-muted);
  font-size: 0.95rem;
}

.preview-section {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.preview-section h4 {
  margin: 0;
  font-size: 1.1rem;
  color: var(--ex-text);
}

.preview-option {
  margin: 2px 0;
  padding: 4px 10px;
  border-radius: 8px;
}

.status-loading {
  animation: exBlink 1.4s infinite;
}

/* ============================================================
   Form layout
   ============================================================ */
.ex-form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

/* form-field compat — kept for any shared form-field usage */

/* --- Form inputs (scoped) --- */
.exercise-page input,
.exercise-page select,
.exercise-page textarea {
  border-radius: var(--ex-radius-input);
  border: 1px solid var(--ex-border-strong);
  background: var(--ex-surface);
  color: var(--ex-text);
  padding: 12px 16px;
  font-family: inherit;
  font-size: 1rem;
  outline: none;
  transition: border 0.2s ease, box-shadow 0.2s ease;
}

.exercise-page input:focus,
.exercise-page select:focus,
.exercise-page textarea:focus {
  border-color: var(--ex-accent);
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.15);
}

.exercise-page textarea {
  resize: vertical;
  min-height: 100px;
}

.exercise-page .helper-text {
  margin: 0;
  font-size: 0.88rem;
  color: var(--ex-muted);
}

/* ============================================================
   Buttons
   ============================================================ */
.ex-btn-primary,
.ex-btn-ghost,
.ex-btn-icon {
  border-radius: var(--ex-radius-pill);
  border: none;
  font-family: inherit;
  font-size: 0.95rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
}

/* Primary gradient pill */
.ex-btn-primary {
  background: linear-gradient(120deg, #4dffff, #6c4bff);
  color: #041024;
  font-weight: 600;
  padding: 11px 22px;
}

.ex-btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(77, 255, 255, 0.3);
}

.ex-btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* Ghost button */
.ex-btn-ghost {
  background: transparent;
  border: 1px solid rgba(15, 23, 42, 0.2);
  color: var(--ex-text);
  padding: 10px 20px;
}

.ex-btn-ghost:hover {
  transform: translateY(-1px);
  border-color: var(--ex-accent);
  color: var(--ex-accent);
}

.ex-btn-ghost:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.ex-btn-ghost--danger {
  border-color: rgba(220, 38, 38, 0.4);
  color: var(--ex-danger);
}

.ex-btn-ghost--danger:hover {
  border-color: var(--ex-danger);
  color: var(--ex-danger);
  background: rgba(220, 38, 38, 0.06);
}

/* Icon-only button (reorder / delete) */
.ex-btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: 12px;
  background: transparent;
  border: 1px solid var(--ex-border-strong);
  color: var(--ex-muted);
  font-size: 1rem;
}

.ex-btn-icon:hover {
  border-color: var(--ex-accent);
  color: var(--ex-accent);
  background: rgba(14, 165, 233, 0.06);
}

.ex-btn-icon--danger:hover {
  border-color: var(--ex-danger);
  color: var(--ex-danger);
  background: rgba(220, 38, 38, 0.06);
}

/* Add-question button (dashed) */
.ex-btn-add {
  width: 100%;
  border: 2px dashed rgba(15, 23, 42, 0.2);
  border-radius: var(--ex-radius-card);
  background: transparent;
  color: var(--ex-muted);
  padding: 18px;
  font-family: inherit;
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, background 0.2s ease;
}

.ex-btn-add:hover {
  border-color: var(--ex-accent);
  color: var(--ex-accent);
  background: rgba(14, 165, 233, 0.04);
}

/* ============================================================
   Exercise card
   ============================================================ */
.ex-card {
  background: var(--ex-surface);
  border: 1px solid var(--ex-border);
  border-radius: var(--ex-radius-card);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  position: relative;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.ex-card:hover {
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.08);
}

.ex-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.ex-card-header .ex-card-number {
  font-weight: 700;
  color: var(--ex-accent);
  font-size: 1rem;
}

.ex-card-actions {
  display: flex;
  gap: 6px;
  flex-shrink: 0;
}

.ex-card-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.ex-card-question {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--ex-text);
}

/* --- MCQ option rows --- */
.ex-option-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 14px;
  border: 1px solid var(--ex-border);
  background: rgba(248, 250, 252, 0.6);
  transition: border-color 0.2s ease, background 0.2s ease;
}

.ex-option-row:hover {
  border-color: rgba(15, 23, 42, 0.2);
}

.ex-option-row input[type="radio"],
.ex-option-row input[type="checkbox"] {
  flex-shrink: 0;
  width: 18px;
  height: 18px;
  padding: 0;
  margin: 0;
  accent-color: var(--ex-accent);
}

.ex-option-row input[type="text"] {
  flex: 1;
  border: none;
  background: transparent;
  padding: 4px 0;
  font-size: 0.95rem;
}

.ex-option-row input[type="text"]:focus {
  box-shadow: none;
}

/* Correct answer highlight (preview / answer-key) */
.ex-option-correct {
  border-color: rgba(22, 163, 74, 0.4);
  background: rgba(22, 163, 74, 0.07);
}

.ex-option-correct::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ex-success);
  flex-shrink: 0;
}

/* ============================================================
   Preview panel
   ============================================================ */
.preview-panel {
  background: var(--ex-surface);
  border: 1px solid var(--ex-border);
  border-radius: var(--ex-radius-panel);
  padding: 28px;
  box-shadow: var(--ex-shadow);
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.preview-panel__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.preview-panel__header h2 {
  margin: 0;
  font-size: 1.5rem;
  color: var(--ex-text);
}

.preview-question {
  border: 1px solid var(--ex-border);
  border-radius: 18px;
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: rgba(248, 250, 252, 0.5);
}

.preview-question__number {
  font-weight: 700;
  color: var(--ex-accent);
  font-size: 0.95rem;
}

.preview-question__text {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--ex-text);
}

.preview-question__options {
  display: grid;
  gap: 8px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.preview-answer {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 12px;
  background: rgba(22, 163, 74, 0.08);
  border: 1px solid rgba(22, 163, 74, 0.25);
  color: var(--ex-success);
  font-size: 0.9rem;
  font-weight: 600;
}

/* ============================================================
   Export row
   ============================================================ */
.export-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
  padding-top: 8px;
}

/* ============================================================
   Loading state
   ============================================================ */
.ex-loading {
  position: relative;
  pointer-events: none;
}

.ex-loading::after {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0.65);
  border-radius: var(--ex-radius-panel);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  animation: exBlink 1.4s infinite;
}

@keyframes exBlink {
  0%,
  100% {
    opacity: 0.4;
  }
  50% {
    opacity: 0.85;
  }
}

/* Loading text helper (optional inner element) */
.ex-loading-text {
  animation: exBlink 1.4s infinite;
  color: var(--ex-muted);
  font-size: 0.95rem;
  text-align: center;
  padding: 24px;
}

/* ============================================================
   Empty state
   ============================================================ */
.ex-empty {
  border: 2px dashed rgba(15, 23, 42, 0.18);
  border-radius: var(--ex-radius-card);
  padding: 36px 24px;
  text-align: center;
  color: var(--ex-muted);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.ex-empty__icon {
  font-size: 2rem;
  opacity: 0.5;
}

.ex-empty__text {
  font-size: 0.95rem;
  max-width: 360px;
}

/* ============================================================
   Form actions row (within steps)
   ============================================================ */
.exercise-page .form-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 6px;
}

/* ============================================================
   Utility classes
   ============================================================ */
.exercise-page .text-muted {
  color: var(--ex-muted);
}

.exercise-page .text-accent {
  color: var(--ex-accent);
}

.exercise-page .text-success {
  color: var(--ex-success);
}

.exercise-page .text-danger {
  color: var(--ex-danger);
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 768px) {
  .exercise-shell {
    margin-top: 40px;
    padding: 0 16px;
    gap: 24px;
  }

  .exercise-step {
    padding: 22px;
    border-radius: 22px;
  }

  .ex-form-grid {
    grid-template-columns: 1fr;
  }

  .preview-panel {
    padding: 22px;
    border-radius: 22px;
  }
}

@media (max-width: 520px) {
  .exercise-step {
    padding: 18px;
    border-radius: 18px;
  }

  .step-title {
    font-size: 1.25rem;
  }

  .ex-card {
    padding: 16px;
    border-radius: 18px;
  }

  .export-row {
    flex-direction: column;
    align-items: stretch;
  }

  .export-row .ex-btn-primary,
  .export-row .ex-btn-ghost {
    width: 100%;
  }

  .ex-card-header {
    flex-direction: column;
    gap: 8px;
  }

  .ex-card-actions {
    align-self: flex-end;
  }

  .exercise-page .form-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .exercise-page .form-actions .ex-btn-primary,
  .exercise-page .form-actions .ex-btn-ghost {
    width: 100%;
    justify-content: center;
  }
}

body.theme-neon.exercise-page {
  --ex-text: #e6f4ff;
  --ex-muted: #9db4c7;
  --ex-accent: #67e8f9;
  --ex-success: #4ade80;
  --ex-border: rgba(103, 232, 249, 0.12);
  --ex-border-strong: rgba(103, 232, 249, 0.2);
  --ex-surface: rgba(8, 21, 34, 0.94);
  --ex-bg-tint: rgba(14, 165, 233, 0.12);
  --ex-shadow: 0 24px 56px rgba(0, 0, 0, 0.34);
  background:
    radial-gradient(circle at 16% 10%, rgba(45, 212, 191, 0.12), transparent 24%),
    linear-gradient(180deg, #07131e 0%, #0a1622 48%, #0d1b29 100%);
}

body.theme-neon.exercise-page .exercise-step,
body.theme-neon.exercise-page .preview-panel {
  background: linear-gradient(180deg, rgba(8, 21, 34, 0.96), rgba(10, 24, 38, 0.94));
  border-color: rgba(103, 232, 249, 0.14);
  box-shadow:
    0 24px 56px rgba(0, 0, 0, 0.36),
    inset 0 1px 0 rgba(255,255,255,0.03);
}

body.theme-neon.exercise-page .step-title,
body.theme-neon.exercise-page .preview-panel__header h2,
body.theme-neon.exercise-page .preview-question__text,
body.theme-neon.exercise-page .preview-header h3,
body.theme-neon.exercise-page .preview-section h4 {
  color: #ecfeff;
}

body.theme-neon.exercise-page .step-eyebrow,
body.theme-neon.exercise-page .ex-field span,
body.theme-neon.exercise-page .preview-header p,
body.theme-neon.exercise-page .helper-text,
body.theme-neon.exercise-page .ex-loading-text,
body.theme-neon.exercise-page .text-muted {
  color: #9db4c7;
}

body.theme-neon.exercise-page input,
body.theme-neon.exercise-page select,
body.theme-neon.exercise-page textarea {
  background: rgba(13, 31, 46, 0.94);
  color: #ecfeff;
  border-color: rgba(103, 232, 249, 0.18);
}

body.theme-neon.exercise-page .step-status,
body.theme-neon.exercise-page .ex-difficulty-badge {
  background: rgba(14, 165, 233, 0.14);
  border-color: rgba(103, 232, 249, 0.22);
  color: #7dd3fc;
}

body.theme-neon.exercise-page .preview-question,
body.theme-neon.exercise-page .ex-card,
body.theme-neon.exercise-page .ex-empty {
  background: rgba(13, 31, 46, 0.9);
  border-color: rgba(103, 232, 249, 0.12);
}

body.theme-neon.exercise-page .ex-btn-primary {
  background: linear-gradient(135deg, #14b8a6 0%, #0891b2 100%);
  color: #f8fafc;
  box-shadow: 0 14px 28px rgba(8, 145, 178, 0.28);
}

body.theme-neon.exercise-page .ex-btn-ghost,
body.theme-neon.exercise-page .ex-btn-icon,
body.theme-neon.exercise-page .ex-btn-add {
  background: rgba(18, 43, 60, 0.92);
  color: #e6f4ff;
  border-color: rgba(103, 232, 249, 0.16);
}

body.theme-neon.exercise-page .ex-btn-ghost:hover,
body.theme-neon.exercise-page .ex-btn-icon:hover,
body.theme-neon.exercise-page .ex-btn-add:hover {
  background: rgba(23, 53, 73, 0.98);
  color: #8df5ea;
  border-color: rgba(103, 232, 249, 0.28);
}

body.theme-neon.exercise-page .preview-answer,
body.theme-neon.exercise-page .ex-option-correct {
  background: rgba(22, 163, 74, 0.12);
  border-color: rgba(74, 222, 128, 0.28);
  color: #86efac;
}