/* ==========================================================================
   강석수학 맞춤 시험지 자동 생성기 - 모던 뉴트럴 다크모드 디자인 시스템
   ========================================================================== */

:root {
  /* Base Neutral Dark Palette (네이비 제거 -> 눈이 편안한 옵시디언/차콜 다크모드) */
  --bg-main: #0B0C10;
  --bg-surface: #141620;
  --bg-surface-elevated: #1B1E2B;
  --bg-card: #151822;
  --bg-card-highlight: #181C2A;
  --bg-input: #0F1118;
  
  --border-color: #242938;
  --border-hover: #373E54;
  --border-active: #3B82F6;
  
  /* 4단계 순차 입력 포인트 컬러 시스템 */
  --step1-color: #06B6D4;          /* 1단계 교재 선택: 시안 / 에메랄드 */
  --step1-bg: rgba(6, 182, 212, 0.12);
  --step1-border: rgba(6, 182, 212, 0.35);

  --step2-color: #8B5CF6;          /* 2단계 학생 정보: 바이올렛 / 퍼플 */
  --step2-bg: rgba(139, 92, 246, 0.12);
  --step2-border: rgba(139, 92, 246, 0.35);

  --step3-color: #3B82F6;          /* 3단계 문항 번호: 비비드 로열 블루 */
  --step3-bg: rgba(59, 130, 246, 0.14);
  --step3-border: rgba(59, 130, 246, 0.4);

  --step4-color: #F59E0B;          /* 4단계 표지 서식: 웜 앰버 / 골드 */
  --step4-bg: rgba(245, 158, 11, 0.12);
  --step4-border: rgba(245, 158, 11, 0.35);

  --primary: #3B82F6;
  --primary-hover: #2563EB;
  --primary-glow: rgba(59, 130, 246, 0.3);
  --primary-gradient: linear-gradient(135deg, #3B82F6 0%, #2563EB 50%, #1D4ED8 100%);
  --danger: #EF4444;
  --accent-cyan: #06B6D4;

  /* 눈이 편안한 고대비 텍스트 컬러 (번짐 및 눈부심 방지) */
  --text-heading: #F8FAFC;
  --text-main: #E2E8F0;
  --text-muted: #94A3B8;
  --text-sub: #64748B;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.65);

  --transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Base Reset & Typography */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Pretendard', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Malgun Gothic', sans-serif;
  background-color: var(--bg-main);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.5;
  letter-spacing: -0.015em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* App Container */
.app-container {
  max-width: 1680px;
  margin: 0 auto;
  padding: 1.25rem 2rem 2.5rem;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

/* Top Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.95rem 1.4rem;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 1.1rem;
}

.logo-badge {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid rgba(59, 130, 246, 0.28);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
}

.math-icon {
  font-family: 'Outfit', sans-serif;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
  line-height: 1;
}

.logo-text {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-heading);
}

.header-title-wrap {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.main-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-heading);
}

.sub-badge {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.28);
  color: #34d399;
  border-radius: var(--radius-full);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.user-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  color: var(--text-main);
  font-weight: 500;
}

.user-badge-icon {
  font-size: 0.95rem;
  line-height: 1;
}

.user-badge-name {
  font-weight: 600;
  color: #93C5FD;
}

.header-logout-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.75rem;
  background: rgba(239, 68, 68, 0.08);
  border: 1px solid rgba(239, 68, 68, 0.22);
  color: #F87171;
  font-size: 0.8rem;
  font-weight: 500;
  border-radius: var(--radius-full);
  text-decoration: none;
  transition: var(--transition);
}

.header-logout-btn:hover {
  background: rgba(239, 68, 68, 0.18);
  border-color: rgba(239, 68, 68, 0.4);
  color: #FCA5A5;
  transform: translateY(-1px);
}

/* ==========================================================================
   Step Guide Rail (단계별 네비게이션 가이드 레일)
   ========================================================================== */
.step-guide-rail {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 0.65rem 1.25rem;
  margin-bottom: 1.1rem;
  box-shadow: var(--shadow-sm);
}

.step-guide-node {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  cursor: pointer;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  user-select: none;
}

.step-guide-node:hover {
  background: var(--bg-surface-elevated);
  transform: translateY(-1px);
}

.step-guide-node.active {
  background: rgba(255, 255, 255, 0.05);
}

.step-flash-highlight {
  animation: cardFlashPulse 1.2s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes cardFlashPulse {
  0% { transform: scale(1); box-shadow: var(--shadow-sm); }
  40% { transform: scale(1.012); box-shadow: 0 0 24px rgba(59, 130, 246, 0.35); border-color: rgba(59, 130, 246, 0.7); }
  100% { transform: scale(1); box-shadow: var(--shadow-sm); }
}

.step-node-pill {
  width: 26px;
  height: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.02em;
  transition: transform 0.2s ease;
}

.step-guide-node:hover .step-node-pill {
  transform: scale(1.08);
}

.step-pill-1 { background: linear-gradient(135deg, #06B6D4, #0891B2); }
.step-pill-2 { background: linear-gradient(135deg, #8B5CF6, #7C3AED); }
.step-pill-3 { background: linear-gradient(135deg, #3B82F6, #1D4ED8); box-shadow: 0 0 10px rgba(59, 130, 246, 0.4); }
.step-pill-4 { background: linear-gradient(135deg, #F59E0B, #D97706); }

.step-node-label {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-heading);
}

.step-guide-arrow {
  font-size: 1.1rem;
  color: #384158;
  font-weight: 700;
}

/* ==========================================================================
   Workspace Grid
   ========================================================================== */
.workspace {
  display: grid;
  grid-template-columns: 560px 1fr;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 1280px) {
  .workspace {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   Step Cards (단계별 시각적 차별화)
   ========================================================================== */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 1.1rem;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: var(--transition);
}

.card:hover {
  border-color: var(--border-hover);
}

/* 1단계 교재 선택 카드 (Cyan Accent) */
.step-1-card {
  border-left: 4px solid var(--step1-color);
}
.step-1-card:hover {
  border-color: var(--border-hover);
  border-left-color: var(--step1-color);
}

/* 2단계 학생 정보 카드 (Purple Accent) */
.step-2-card {
  border-left: 4px solid var(--step2-color);
}
.step-2-card:hover {
  border-color: var(--border-hover);
  border-left-color: var(--step2-color);
}

/* 3단계 문항 번호 선택 카드 (핵심 강조 - Blue Accent + Subtle Lift) */
.step-3-card {
  border-left: 4px solid var(--step3-color);
  background: linear-gradient(180deg, rgba(59, 130, 246, 0.04) 0%, var(--bg-card) 70px);
}
.step-3-card:hover {
  border-color: var(--border-hover);
  border-left-color: var(--step3-color);
}

/* 4단계 상세 양식 카드 (Amber Accent) */
.step-4-card {
  border-left: 4px solid var(--step4-color);
}
.step-4-card:hover {
  border-color: var(--border-hover);
  border-left-color: var(--step4-color);
}

/* Card Header */
.card-header {
  padding: 0.9rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-color);
  background: rgba(255, 255, 255, 0.015);
}

.card-header.pointer {
  cursor: pointer;
  user-select: none;
}

.card-title {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.card-title h3 {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-heading);
}

.range-sub-label {
  font-size: 0.8rem;
  color: var(--step3-color);
  font-weight: 600;
}

/* Step Number Badges */
.step-num {
  width: 22px;
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  font-size: 0.75rem;
  font-weight: 800;
  color: #fff;
}

.step-num-1 { background: var(--step1-color); }
.step-num-2 { background: var(--step2-color); }
.step-num-3 { background: var(--step3-color); }
.step-num-4 { background: var(--step4-color); }

/* Step Status Tag */
.badge-status-pill {
  font-size: 0.74rem;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-full);
  background: var(--step1-bg);
  border: 1px solid var(--step1-border);
  color: var(--step1-color);
  font-weight: 600;
}

.step-4-header-right {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.step-status-tag {
  font-size: 0.72rem;
  padding: 0.18rem 0.55rem;
  border-radius: var(--radius-full);
  background: var(--step4-bg);
  border: 1px solid var(--step4-border);
  color: var(--step4-color);
  font-weight: 600;
}

.card-body {
  padding: 1.25rem;
}

/* ==========================================================================
   Form Controls (다크모드 고대비 정밀 렌더링)
   ========================================================================== */
.form-group {
  margin-bottom: 0.95rem;
}

.form-group:last-child {
  margin-bottom: 0;
}

.form-group label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.input-header-flex {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.35rem;
}

.input-header-flex label {
  margin-bottom: 0;
}

.example-text {
  font-size: 0.75rem;
  color: var(--text-sub);
}

.example-text code {
  background: rgba(255, 255, 255, 0.06);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  color: #93C5FD;
  font-family: monospace;
}

.form-control {
  width: 100%;
  padding: 0.72rem 0.95rem;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-heading);
  font-size: 0.92rem;
  font-family: inherit;
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.22);
}

.code-input {
  font-family: 'Outfit', 'Pretendard', monospace;
  font-weight: 600;
  letter-spacing: 0.02em;
  resize: vertical;
}

.input-with-icon {
  position: relative;
  display: flex;
  align-items: center;
}

.input-with-icon svg {
  position: absolute;
  left: 0.85rem;
  color: var(--text-sub);
  pointer-events: none;
}

.input-with-icon .form-control {
  padding-left: 2.5rem;
}

.form-hint {
  display: block;
  font-size: 0.75rem;
  color: var(--text-sub);
  margin-top: 0.35rem;
}

/* Textbook Select Custom */
.textbook-select {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-heading);
  background-color: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  cursor: pointer;
  transition: var(--transition);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2306B6D4' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  appearance: none;
  -webkit-appearance: none;
  padding-right: 2.5rem;
}

.textbook-select:hover {
  border-color: var(--step1-color);
}

.textbook-select:focus {
  border-color: var(--step1-color);
  box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.2);
  outline: none;
}

/* Mode Toggle (학생 정보 개별 vs 일괄) */
.mode-toggle {
  display: flex;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 2px;
}

.toggle-btn {
  padding: 0.32rem 0.7rem;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  border-radius: calc(var(--radius-sm) - 2px);
  transition: var(--transition);
}

.toggle-btn.active {
  background: var(--step2-color);
  color: #fff;
  box-shadow: 0 2px 6px rgba(139, 92, 246, 0.35);
}

/* Problem Count Badge */
.problem-count-badge {
  font-size: 0.82rem;
  color: var(--text-muted);
  background: var(--step3-bg);
  border: 1px solid var(--step3-border);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
}

.problem-count-badge strong {
  color: #60A5FA;
  font-size: 0.92rem;
}

/* Quick Tools */
.quick-tools {
  margin-top: 0.75rem;
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.tool-btn {
  padding: 0.35rem 0.7rem;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.76rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.tool-btn:hover {
  background: #252A3B;
  color: var(--text-heading);
}

.tool-btn.danger:hover {
  background: rgba(239, 68, 68, 0.15);
  border-color: var(--danger);
  color: #F87171;
}

/* Selected Tags Container */
.selected-tags-container {
  margin-top: 0.85rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  max-height: 85px;
  overflow-y: auto;
  padding: 0.45rem;
  background: var(--bg-input);
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border-color);
}

.tag-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: rgba(59, 130, 246, 0.14);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #93C5FD;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-full);
}

.tag-badge .remove-tag {
  cursor: pointer;
  opacity: 0.6;
}

.tag-badge .remove-tag:hover {
  opacity: 1;
  color: #fff;
}

/* Form Row */
.form-row {
  display: flex;
  gap: 1rem;
  margin-bottom: 0.85rem;
}

.form-row .col {
  flex: 1;
}

.accordion-icon {
  font-size: 0.75rem;
  color: var(--step4-color);
  transition: transform 0.2s ease;
}

.accordion-icon.collapsed {
  transform: rotate(-90deg);
}

/* Checkbox */
.form-check-group {
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-color);
}

.checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-heading);
  user-select: none;
}

.checkbox-label input {
  display: none;
}

.checkbox-custom {
  width: 18px;
  height: 18px;
  border: 2px solid var(--border-color);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  background: var(--bg-input);
}

.checkbox-label input:checked + .checkbox-custom {
  background: var(--primary);
  border-color: var(--primary);
}

.checkbox-label input:checked + .checkbox-custom::after {
  content: '✓';
  color: #fff;
  font-size: 0.75rem;
  font-weight: 900;
}

.spec-note {
  display: block;
  font-size: 0.75rem;
  color: var(--text-sub);
  margin-top: 0.35rem;
}

/* ==========================================================================
   Character Mascot Card (다크모드 스타일링)
   ========================================================================== */
.character-control-card {
  display: flex;
  align-items: center;
  gap: 0.95rem;
  margin-top: 0.85rem;
  padding: 0.8rem 1rem;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.character-control-card:hover {
  border-color: var(--step4-border);
}

.character-preview-wrap {
  width: 52px;
  height: 60px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #FAFBFD;
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-sm);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  overflow: hidden;
  padding: 3px;
}

.character-thumb-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform 0.2s ease;
}

.character-thumb-img:hover {
  transform: scale(1.08);
}

.character-info-wrap {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 0;
}

.character-title {
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--text-heading);
}

.character-desc {
  font-size: 0.74rem;
  color: var(--text-muted);
}

.character-btn-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-top: 0.25rem;
}

.character-upload-btn {
  font-size: 0.74rem;
  padding: 0.3rem 0.6rem;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
  border-radius: var(--radius-sm);
}

.character-status {
  font-size: 0.72rem;
  color: var(--accent-cyan);
}

/* ==========================================================================
   Action Buttons
   ========================================================================== */
.action-buttons-wrap {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.85rem 1.4rem;
  font-size: 0.92rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: var(--transition);
  user-select: none;
}

.btn-primary {
  background: var(--primary-gradient);
  color: #fff;
  flex: 1.8;
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(59, 130, 246, 0.5);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-color);
  color: var(--text-heading);
}

.btn-secondary:hover {
  background: #252A3C;
  border-color: var(--border-hover);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-muted);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-heading);
  border-color: var(--border-hover);
}

.btn-sm {
  padding: 0.4rem 0.8rem;
  font-size: 0.78rem;
  border-radius: var(--radius-sm);
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-color);
  color: var(--text-heading);
  cursor: pointer;
}

/* ==========================================================================
   Right Preview Panel
   ========================================================================== */
.preview-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-md);
  position: sticky;
  top: 1.25rem;
  min-height: 800px;
}

.preview-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border-color);
  gap: 0.75rem;
  flex-wrap: wrap;
}

.preview-title-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.preview-title-group h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-heading);
}

.preview-status {
  font-size: 0.74rem;
  font-weight: 600;
  padding: 0.18rem 0.55rem;
  border-radius: var(--radius-full);
  background: rgba(16, 185, 129, 0.14);
  color: #34D399;
}

.preview-summary-badge {
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-full);
  background: rgba(59, 130, 246, 0.14);
  color: #60A5FA;
  border: 1px solid rgba(59, 130, 246, 0.28);
}

/* 3대 뷰어 액션 버튼 그룹 (가로폭 확대, 창 대형 확대, 새 창으로 크게 보기) */
.preview-header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.preview-tool-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.32rem 0.75rem;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.14);
  color: #e2e8f0;
  font-size: 0.78rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.16s ease;
  user-select: none;
}

.preview-tool-btn:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.28);
  color: #fff;
  transform: translateY(-1px);
}

.preview-tool-btn:active {
  transform: translateY(0);
}

.preview-tool-btn.active {
  background: rgba(59, 130, 246, 0.22);
  border-color: #3B82F6;
  color: #93C5FD;
  box-shadow: 0 0 10px rgba(59, 130, 246, 0.3);
}

.preview-tool-btn.btn-highlight-green {
  background: rgba(16, 185, 129, 0.16);
  border: 1px solid rgba(16, 185, 129, 0.45);
  color: #34D399;
  font-weight: 600;
}

.preview-tool-btn.btn-highlight-green:hover {
  background: rgba(16, 185, 129, 0.28);
  border-color: #10B981;
  color: #6EE7B7;
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.35);
}

.page-nav-controls {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  padding: 0.15rem 0.5rem;
}

.nav-arrow {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.2rem 0.4rem;
  font-size: 0.75rem;
  border-radius: 4px;
}

.nav-arrow:hover {
  color: #fff;
}

.page-indicator {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-heading);
  min-width: 45px;
  text-align: center;
}

/* Canvas / Sheet Container (순수 다크 캔버스 위에서 백색 PDF가 또렷하게 부각) */
.preview-canvas-container {
  flex: 1;
  background: #090A0E;
  border-radius: var(--radius-sm);
  border: 1px solid #1C202E;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: auto;
  padding: 1.5rem;
  min-height: 620px;
  transition: all 0.2s ease;
}

/* 가로폭 확대 (Fit Width) 활성화 모드 */
.preview-canvas-container.fit-width {
  display: block;
  overflow-y: auto;
  text-align: center;
  padding: 1.5rem 1rem;
}

.preview-canvas-container.fit-width .preview-viewport {
  width: 100%;
  max-width: none;
  display: block;
}

.preview-canvas-container.fit-width .preview-sheet {
  max-height: none;
  width: 100%;
  max-width: 900px;
  margin: 0 auto;
  display: block;
}

.preview-loading {
  position: absolute;
  inset: 0;
  background: rgba(9, 10, 14, 0.88);
  backdrop-filter: blur(4px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  z-index: 10;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(59, 130, 246, 0.2);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.preview-viewport {
  max-width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.preview-sheet {
  max-width: 100%;
  max-height: 640px;
  width: auto;
  height: auto;
  box-shadow: 0 12px 35px rgba(0, 0, 0, 0.85);
  border-radius: 4px;
  background: #fff;
  transition: transform 0.2s ease;
}

/* Thumbnails Bar */
.page-thumbnails-bar {
  margin-top: 1rem;
  display: flex;
  gap: 0.75rem;
  overflow-x: auto;
  padding: 0.5rem 0.25rem;
}

.thumb-btn {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  background: var(--bg-input);
  border: 2px solid var(--border-color);
  border-radius: 6px;
  padding: 0.35rem;
  cursor: pointer;
  transition: var(--transition);
}

.thumb-btn img {
  width: 50px;
  height: 70px;
  object-fit: cover;
  border-radius: 3px;
  background: #fff;
}

.thumb-btn span {
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--text-muted);
}

.thumb-btn.active {
  border-color: var(--primary);
  box-shadow: 0 0 12px var(--primary-glow);
}

.thumb-btn.active span {
  color: #60A5FA;
}

.thumb-btn.thumb-btn-answer {
  border-color: #10B981 !important;
  background: rgba(16, 185, 129, 0.08);
}

.thumb-btn.thumb-btn-answer span {
  color: #10B981 !important;
  font-weight: 800;
}

.thumb-btn.thumb-btn-answer.active {
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.45);
}

/* ==========================================================================
   Modal Problem Gallery
   ========================================================================== */
/* ==========================================================================
   Character Mascot Control Card
   ========================================================================== */
.character-control-card {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 0.9rem 1.1rem;
  margin-top: 0.9rem;
  transition: var(--transition);
}

.character-control-card:hover {
  border-color: var(--border-hover);
}

.character-preview-wrap {
  width: 58px;
  height: 58px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px;
  flex-shrink: 0;
}

.character-thumb-img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.4));
}

.character-info-wrap {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  flex: 1;
}

.character-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-heading);
}

.character-desc {
  font-size: 0.76rem;
  color: var(--text-muted);
}

.character-btn-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-top: 0.4rem;
}

.character-upload-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  cursor: pointer;
  padding: 0.35rem 0.75rem;
  font-size: 0.78rem;
}

.btn-subtle {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.78rem;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
}

.btn-subtle:hover {
  background: rgba(239, 68, 68, 0.15);
  border-color: rgba(239, 68, 68, 0.35);
  color: #f87171;
}

.btn-save-char {
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.4);
  color: #34d399;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.btn-save-char:hover {
  background: rgba(16, 185, 129, 0.28);
  border-color: #34d399;
  color: #ffffff;
  box-shadow: 0 0 10px rgba(52, 211, 153, 0.3);
}

.character-status {
  font-size: 0.75rem;
  font-weight: 600;
  color: #34d399;
}

/* ==========================================================================
   Olympus Hierarchical Picker Panel
   ========================================================================== */
.olympus-picker-panel {
  background: linear-gradient(135deg, rgba(30, 41, 59, 0.75), rgba(15, 23, 42, 0.9));
  border: 1px solid rgba(56, 189, 248, 0.28);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  margin-bottom: 1.25rem;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.45);
  animation: fadeInDown 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.olympus-picker-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.9rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.olympus-badge {
  font-size: 0.82rem;
  font-weight: 700;
  color: #38bdf8;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  letter-spacing: -0.01em;
}

.olympus-guide-txt {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.olympus-controls-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.9rem;
  margin-bottom: 0.9rem;
}

@media (max-width: 640px) {
  .olympus-controls-grid {
    grid-template-columns: 1fr;
  }
}

.olympus-select {
  background: rgba(15, 23, 42, 0.85);
  border-color: rgba(56, 189, 248, 0.3);
  font-weight: 600;
  color: #f1f5f9;
}

.olympus-select:focus {
  border-color: #38bdf8;
  box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.2);
}

.olympus-type-pills {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}

.type-pill {
  flex: 1;
  min-width: 90px;
  background: rgba(15, 23, 42, 0.65);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-sm);
  padding: 0.45rem 0.55rem;
  color: var(--text-muted);
  font-size: 0.76rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  transition: all 0.18s ease;
}

.type-pill:hover {
  background: rgba(56, 189, 248, 0.12);
  border-color: rgba(56, 189, 248, 0.35);
  color: #f8fafc;
}

.type-pill.active {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.35), rgba(14, 165, 233, 0.25));
  border-color: #38bdf8;
  color: #ffffff;
  box-shadow: 0 0 12px rgba(56, 189, 248, 0.28);
}

.type-pill .pill-range {
  font-size: 0.68rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.55);
}

.type-pill.active .pill-range {
  color: #7dd3fc;
}

.olympus-add-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: rgba(15, 23, 42, 0.6);
  padding: 0.65rem 0.75rem;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.olympus-input-wrap {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.current-target-label {
  font-size: 0.72rem;
  font-weight: 700;
  color: #38bdf8;
}

.olympus-add-row input {
  background: rgba(15, 23, 42, 0.9);
  border-color: rgba(255, 255, 255, 0.15);
  font-size: 0.85rem;
  padding: 0.4rem 0.65rem;
}

.olympus-add-row input:focus {
  border-color: #38bdf8;
  box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.25);
}

/* Olympus Customized Tags */
.tag-badge.olympus-badge-type-standard {
  background: rgba(37, 99, 235, 0.2);
  border-color: rgba(59, 130, 246, 0.45);
  color: #93c5fd;
}

.tag-badge.olympus-badge-type-written {
  background: rgba(16, 185, 129, 0.2);
  border-color: rgba(52, 211, 153, 0.45);
  color: #6ee7b7;
}

.tag-badge.olympus-badge-type-challenge {
  background: rgba(168, 85, 247, 0.2);
  border-color: rgba(192, 132, 252, 0.45);
  color: #d8b4fe;
}

/* ==========================================================================
   대형 전체화면 미리보기 모달 (Large Preview Modal)
   ========================================================================== */
.preview-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 99999;
  background: rgba(5, 7, 12, 0.9);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
  animation: modalFadeIn 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalFadeIn {
  from { opacity: 0; transform: scale(0.98); }
  to { opacity: 1; transform: scale(1); }
}

.preview-modal-container {
  background: #0D111A;
  border: 1px solid #222B3E;
  border-radius: 12px;
  width: 95vw;
  max-width: 1400px;
  height: 94vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.85);
}

.preview-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.4rem;
  border-bottom: 1px solid #1E273A;
  background: #111624;
  gap: 1rem;
  flex-wrap: wrap;
}

.preview-modal-title-wrap {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.modal-badge {
  font-size: 0.76rem;
  font-weight: 700;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-full);
  background: rgba(59, 130, 246, 0.2);
  color: #60A5FA;
  border: 1px solid rgba(59, 130, 246, 0.4);
}

.preview-modal-title-wrap h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: #F1F5F9;
  margin: 0;
}

.modal-page-info {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
}

.preview-modal-tools {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.modal-tool-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #E2E8F0;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.16s ease;
}

.modal-tool-btn:hover {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.3);
  color: #fff;
  transform: translateY(-1px);
}

.modal-tool-btn.btn-highlight-green {
  background: rgba(16, 185, 129, 0.2);
  border-color: rgba(16, 185, 129, 0.5);
  color: #34D399;
}

.modal-tool-btn.btn-highlight-green:hover {
  background: rgba(16, 185, 129, 0.32);
  border-color: #10B981;
  color: #6EE7B7;
}

.modal-tool-btn.btn-close-modal {
  background: rgba(239, 68, 68, 0.15);
  border-color: rgba(239, 68, 68, 0.4);
  color: #F87171;
}

.modal-tool-btn.btn-close-modal:hover {
  background: rgba(239, 68, 68, 0.3);
  border-color: #EF4444;
  color: #FECACA;
}

.preview-modal-body {
  flex: 1;
  overflow-y: auto;
  overflow-x: auto;
  background: #06080D;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 2rem 1rem;
}

.modal-sheet-wrap {
  display: flex;
  justify-content: center;
  width: 100%;
}

.modal-sheet-img {
  max-height: 80vh;
  width: auto;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.95);
  border-radius: 4px;
  background: #fff;
  transition: all 0.2s ease;
}

.modal-sheet-img.fit-width {
  max-height: none;
  width: 100%;
  max-width: 950px;
}

.preview-modal-footer {
  padding: 0.65rem 1.25rem;
  border-top: 1px solid #1E273A;
  background: #0E121E;
  overflow-x: auto;
}

.modal-thumbnails-bar {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  align-items: center;
}