/* ==============================================================================
   [style.css] SmartFit for 셀러 - 공식 사용자 매뉴얼 & Q&A 스타일시트
   - 현대적인 다크 모드 & 글래스모피즘 기반 프리미엄 UI
   - 반응형 레이아웃 (모바일, 태블릿, 데스크톱 최적화)
   - 부드러운 인터랙션 및 마이크로 애니메이션
   ============================================================================== */

:root {
  /* 색상 토큰 (Color Palette) */
  --bg-main: #070b14;
  --bg-sidebar: #0c1322;
  --bg-card: rgba(18, 26, 44, 0.75);
  --bg-card-hover: rgba(28, 39, 66, 0.85);
  --bg-card-solid: #111a2e;
  --bg-elevated: #16223b;
  --bg-pill: rgba(255, 255, 255, 0.06);

  /* 테두리 (Borders) */
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-light: rgba(255, 255, 255, 0.14);
  --border-accent: rgba(56, 189, 248, 0.35);
  --border-glow: rgba(59, 130, 246, 0.4);

  /* 브랜드 & 액센트 (Brand & Accents) */
  --primary: #2563eb;
  --primary-light: #38bdf8;
  --primary-glow: rgba(56, 189, 248, 0.25);
  --accent-cyan: #06b6d4;
  --emerald: #10b981;
  --emerald-light: #34d399;
  --emerald-glow: rgba(16, 185, 129, 0.25);
  --amber: #f59e0b;
  --amber-light: #fbbf24;
  --rose: #f43f5e;
  --purple: #8b5cf6;

  /* 타이포그래피 (Typography) */
  --text-main: #f8fafc;
  --text-title: #ffffff;
  --text-sub: #94a3b8;
  --text-muted: #64748b;

  /* 라운딩 (Border Radius) */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* 그림자 (Shadows) */
  --shadow-sm: 0 2px 6px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 10px 25px -5px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 20px 40px -10px rgba(0, 0, 0, 0.65);
  --shadow-glow: 0 0 35px rgba(56, 189, 248, 0.16);

  /* 트랜지션 (Transitions) */
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 1. 기본 리셋 및 글로벌 스타일 */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.65;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 미려한 오로라 배경 조명 */
body::before {
  content: "";
  position: fixed;
  top: -15%;
  left: 15%;
  width: 55vw;
  height: 55vh;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.13) 0%, rgba(6, 182, 212, 0.04) 50%, transparent 75%);
  pointer-events: none;
  z-index: 0;
  filter: blur(40px);
}

body::after {
  content: "";
  position: fixed;
  bottom: -10%;
  right: 10%;
  width: 45vw;
  height: 45vh;
  background: radial-gradient(circle, rgba(16, 185, 129, 0.09) 0%, rgba(37, 99, 235, 0.03) 60%, transparent 80%);
  pointer-events: none;
  z-index: 0;
  filter: blur(50px);
}

/* 2. 전체 앱 쉘 레이아웃 */
.page-wrapper {
  display: flex;
  min-height: 100vh;
  position: relative;
  z-index: 1;
}

/* 3. 좌측 고정 네비게이션 사이드바 (Sidebar) */
.sidebar {
  width: 320px;
  height: 100vh;
  position: sticky;
  top: 0;
  background: rgba(12, 19, 34, 0.94);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-right: 1px solid var(--border-subtle);
  padding: 24px 20px 20px;
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  z-index: 100;
  transition: transform var(--transition-base);
}

/* 사이드바 브랜드 헤더 */
.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 16px;
  text-decoration: none;
  color: inherit;
}

.brand-icon-wrap {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
  flex-shrink: 0;
  overflow: hidden;
  padding: 4px;
}

.brand-icon-wrap img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 6px;
}

.brand-title-wrap {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.4px;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 6px;
}

.brand-badge {
  font-size: 10.5px;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.35);
  color: var(--primary-light);
  padding: 1px 7px;
  border-radius: var(--radius-full);
  font-weight: 700;
}

.brand-subtitle {
  font-size: 12px;
  color: var(--text-sub);
  margin-top: 2px;
}

/* 검색 필터 바 */
.sidebar-search {
  position: relative;
  margin-bottom: 18px;
}

.search-input-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.search-icon {
  position: absolute;
  left: 12px;
  font-size: 14px;
  color: var(--text-muted);
  pointer-events: none;
}

.search-input {
  width: 100%;
  padding: 10px 14px 10px 34px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 13.5px;
  outline: none;
  transition: all var(--transition-fast);
}

.search-input:focus {
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--primary-light);
  box-shadow: 0 0 14px var(--primary-glow);
}

.search-input::placeholder {
  color: var(--text-muted);
}

.search-clear-btn {
  position: absolute;
  right: 10px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 14px;
  cursor: pointer;
  display: none;
}

/* 탭 전환 스위치 (매뉴얼 <-> Q&A) */
.nav-tab-switcher {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: rgba(255, 255, 255, 0.04);
  padding: 4px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  margin-bottom: 16px;
  gap: 4px;
}

.tab-btn {
  background: transparent;
  border: none;
  padding: 8px 10px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-sub);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: all var(--transition-fast);
}

.tab-btn:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.05);
}

.tab-btn.active {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.4);
}

/* 네비게이션 목차 리스트 */
.sidebar-nav-container {
  flex: 1;
  overflow-y: auto;
  padding-right: 4px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.sidebar-nav-container::-webkit-scrollbar {
  width: 4px;
}

.sidebar-nav-container::-webkit-scrollbar-track {
  background: transparent;
}

.sidebar-nav-container::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.12);
  border-radius: 2px;
}

.nav-section-title {
  font-size: 11px;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  margin: 12px 6px 4px;
}

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-item a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  color: var(--text-sub);
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  position: relative;
}

.nav-item a:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.05);
  transform: translateX(3px);
}

.nav-item.active a {
  color: #ffffff;
  background: rgba(37, 99, 235, 0.18);
  border-left: 3px solid var(--primary-light);
  font-weight: 700;
}

.nav-item-num {
  width: 22px;
  height: 22px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-sub);
  font-size: 11.5px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.nav-item.active .nav-item-num {
  background: var(--primary);
  color: #ffffff;
}

.nav-item-text {
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 사이드바 푸터 */
.sidebar-footer {
  padding-top: 14px;
  border-top: 1px solid var(--border-subtle);
  font-size: 12px;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.sidebar-status-pill {
  display: flex;
  align-items: center;
  gap: 8px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.25);
  color: var(--emerald-light);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: 11.5px;
  font-weight: 600;
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--emerald-light);
  box-shadow: 0 0 8px var(--emerald);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); opacity: 0.8; }
  50% { transform: scale(1.15); opacity: 1; }
  100% { transform: scale(0.95); opacity: 0.8; }
}

/* 4. 메인 콘텐츠 뷰포트 (Main Content Area) */
.main-content {
  flex: 1;
  padding: 40px 60px 120px;
  max-width: 1180px;
  min-width: 0;
}

/* 모바일 햄버거 토글 헤더 (데스크톱 숨김) */
.mobile-topbar {
  display: none;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  background: rgba(12, 19, 34, 0.95);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 90;
}

.btn-mobile-menu {
  background: transparent;
  border: 1px solid var(--border-light);
  color: #ffffff;
  padding: 8px 12px;
  border-radius: 6px;
  font-size: 18px;
  cursor: pointer;
}

/* 5. 히어로 헤더 섹션 (Hero Banner) */
.hero-banner {
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.18) 0%, rgba(6, 182, 212, 0.12) 50%, rgba(17, 26, 46, 0.8) 100%);
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-xl);
  padding: 40px 44px;
  margin-bottom: 48px;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.hero-banner::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.hero-badge-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.pill-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: var(--primary-light);
  padding: 5px 14px;
  border-radius: var(--radius-full);
  font-size: 12.5px;
  font-weight: 700;
}

.pill-badge.green {
  background: rgba(16, 185, 129, 0.15);
  border-color: rgba(16, 185, 129, 0.4);
  color: var(--emerald-light);
}

.hero-title {
  font-size: 32px;
  font-weight: 900;
  line-height: 1.35;
  margin-bottom: 14px;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #ffffff 20%, #e2e8f0 70%, #94a3b8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 15.5px;
  color: #cbd5e1;
  max-width: 820px;
  line-height: 1.7;
  margin-bottom: 26px;
}

/* 주요 지원 플랫폼 칩 목록 */
.platform-chips {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.chip-label {
  font-size: 12.5px;
  color: var(--text-muted);
  margin-right: 4px;
  font-weight: 600;
}

.platform-chip {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: #e2e8f0;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  transition: all var(--transition-fast);
}

.platform-chip:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--primary-light);
  color: #ffffff;
  transform: translateY(-1px);
}

/* 6. 매뉴얼 섹션 (Manual Items) */
.section-wrapper {
  margin-bottom: 64px;
  scroll-margin-top: 36px;
}

.manual-card {
  background: var(--bg-card);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.manual-card:hover {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-lg), 0 0 25px rgba(56, 189, 248, 0.08);
}

/* 카드 상단 헤더 */
.card-header-bar {
  padding: 22px 28px;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(255, 255, 255, 0.02);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: 14px;
}

.item-badge-num {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: rgba(37, 99, 235, 0.2);
  color: var(--primary-light);
  border: 1px solid rgba(56, 189, 248, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 16px;
  flex-shrink: 0;
}

.item-badge-num.green {
  background: rgba(16, 185, 129, 0.2);
  color: var(--emerald-light);
  border-color: rgba(16, 185, 129, 0.4);
}

.item-badge-num.amber {
  background: rgba(245, 158, 11, 0.2);
  color: var(--amber-light);
  border-color: rgba(245, 158, 11, 0.4);
}

.item-badge-num.purple {
  background: rgba(139, 92, 246, 0.2);
  color: #c084fc;
  border-color: rgba(139, 92, 246, 0.4);
}

.card-title-text {
  font-size: 22px;
  font-weight: 800;
  color: #ffffff;
  letter-spacing: -0.3px;
}

.card-header-tags {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.tag-badge {
  font-size: 12px;
  background: var(--bg-pill);
  border: 1px solid var(--border-light);
  color: var(--text-sub);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  font-weight: 600;
}

/* 동영상 플레이어 쇼케이스 컨테이너 (Mac OS 윈도우 스타일 프레임) */
.video-frame-container {
  padding: 24px 28px 20px;
}

.video-mockup-window {
  background: #090e1a;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 12px 36px rgba(0, 0, 0, 0.6);
}

.mockup-header {
  background: #111a2e;
  padding: 10px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  gap: 12px;
}

.mockup-controls {
  display: flex;
  align-items: center;
  gap: 7px;
}

.mockup-dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
}

.mockup-dot.red { background: #ef4444; }
.mockup-dot.yellow { background: #f59e0b; }
.mockup-dot.green { background: #10b981; }

.mockup-title-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12.5px;
  color: var(--text-sub);
  background: rgba(0, 0, 0, 0.3);
  padding: 4px 14px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.06);
  max-width: 500px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.mockup-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.btn-yt-direct {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 11.5px;
  color: var(--primary-light);
  text-decoration: none;
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid rgba(56, 189, 248, 0.25);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: all var(--transition-fast);
}

.btn-yt-direct:hover {
  background: rgba(56, 189, 248, 0.2);
  color: #ffffff;
  border-color: var(--primary-light);
}

/* 반응형 16:9 유튜브 iframe 컨테이너 */
.video-embed-aspect {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #050811;
}

.video-embed-aspect iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* 카드 본문 상세 설명 영역 */
.card-body-content {
  padding: 16px 28px 32px;
}

.content-intro-lead {
  font-size: 15.5px;
  color: #cbd5e1;
  line-height: 1.75;
  margin-bottom: 24px;
}

/* 단계별 가이드 리스트 (Step-by-step Flow) */
.steps-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 24px;
}

.step-card-row {
  display: flex;
  gap: 16px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  transition: all var(--transition-fast);
}

.step-card-row:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--border-light);
  transform: translateX(4px);
}

.step-number-pill {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-light);
  color: var(--primary-light);
  font-size: 14px;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-details {
  flex: 1;
}

.step-title-line {
  font-size: 16px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.step-desc-text {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.65;
}

.step-desc-text strong {
  color: #e2e8f0;
}

.step-desc-text code {
  background: rgba(56, 189, 248, 0.12);
  color: var(--primary-light);
  padding: 2px 7px;
  border-radius: 4px;
  font-family: 'JetBrains Mono', Consolas, monospace;
  font-size: 13px;
  border: 1px solid rgba(56, 189, 248, 0.25);
}

/* 하이라이트 콜아웃 박스 (Tip, Note, Warning) */
.callout-box {
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-top: 20px;
  display: flex;
  gap: 14px;
  align-items: flex-start;
  font-size: 14px;
  line-height: 1.65;
}

.callout-box.tip {
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #a7f3d0;
}

.callout-box.tip .callout-icon {
  color: var(--emerald-light);
  font-size: 18px;
  flex-shrink: 0;
}

.callout-box.info {
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: #bae6fd;
}

.callout-box.info .callout-icon {
  color: var(--primary-light);
  font-size: 18px;
  flex-shrink: 0;
}

.callout-box.warn {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.3);
  color: #fde68a;
}

.callout-box.warn .callout-icon {
  color: var(--amber-light);
  font-size: 18px;
  flex-shrink: 0;
}

.callout-content {
  flex: 1;
}

.callout-title {
  font-weight: 700;
  margin-bottom: 4px;
  color: #ffffff;
}

/* 코드 복사 원클릭 버튼 */
.copy-badge-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: #38bdf8;
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  margin-left: 6px;
  transition: all var(--transition-fast);
}

.copy-badge-btn:hover {
  background: rgba(56, 189, 248, 0.3);
  color: #ffffff;
  transform: translateY(-1px);
}

/* 단축키 키보드 뱃지 */
kbd {
  display: inline-block;
  background: #1e293b;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-bottom: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 5px;
  padding: 1px 7px;
  font-size: 12px;
  font-weight: 700;
  color: #f8fafc;
  font-family: inherit;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

/* 7. Q&A 아코디언 섹션 (FAQ & Questions) */
.faq-section {
  margin-top: 64px;
  scroll-margin-top: 36px;
}

.faq-header {
  margin-bottom: 28px;
}

.faq-title {
  font-size: 28px;
  font-weight: 900;
  color: #ffffff;
  margin-bottom: 8px;
}

.faq-subtitle {
  font-size: 15px;
  color: var(--text-sub);
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all var(--transition-fast);
}

.faq-item.active {
  border-color: var(--border-accent);
  background: var(--bg-card-hover);
}

.faq-question-btn {
  width: 100%;
  padding: 18px 22px;
  background: transparent;
  border: none;
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  text-align: left;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  cursor: pointer;
  transition: color var(--transition-fast);
}

.faq-question-btn:hover {
  color: var(--primary-light);
}

.faq-q-text {
  display: flex;
  align-items: center;
  gap: 12px;
}

.faq-badge-q {
  font-size: 14px;
  font-weight: 900;
  color: var(--primary-light);
  background: rgba(56, 189, 248, 0.15);
  width: 26px;
  height: 26px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.faq-arrow {
  font-size: 14px;
  color: var(--text-muted);
  transition: transform var(--transition-base);
  flex-shrink: 0;
}

.faq-item.active .faq-arrow {
  transform: rotate(180deg);
  color: var(--primary-light);
}

.faq-answer-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-smooth);
}

.faq-answer-inner {
  padding: 0 22px 20px 60px;
  font-size: 14.5px;
  color: #cbd5e1;
  line-height: 1.7;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  margin-top: 4px;
  padding-top: 16px;
}

.faq-answer-inner strong {
  color: #ffffff;
}

.faq-answer-inner p {
  margin-bottom: 8px;
}

.faq-answer-inner p:last-child {
  margin-bottom: 0;
}

/* FAQ 상단 탭 필터 */
.faq-filter-tabs {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 26px;
  flex-wrap: wrap;
}

.faq-filter-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-light);
  color: var(--text-sub);
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 13.5px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.faq-filter-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  color: #ffffff;
  border-color: var(--primary-light);
}

.faq-filter-btn.active {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary-light);
  box-shadow: 0 2px 12px rgba(37, 99, 235, 0.4);
}

/* FAQ 서브 카테고리 헤더 */
.faq-category-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 32px 0 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-subtle);
}

.faq-category-header:first-of-type {
  margin-top: 0;
}

.faq-cat-title {
  font-size: 19px;
  font-weight: 800;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.faq-cat-badge {
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  flex-shrink: 0;
  margin-right: 4px;
}

.faq-cat-badge.ai {
  background: rgba(139, 92, 246, 0.15);
  border: 1px solid rgba(139, 92, 246, 0.4);
  color: #c084fc;
}

.faq-cat-badge.security {
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.4);
  color: var(--emerald-light);
}

.faq-cat-badge.system {
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: var(--primary-light);
}

.faq-cat-badge.general {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #cbd5e1;
}

/* FAQ 답변 내부 스펙 비교 표 */
.spec-table-container {
  overflow-x: auto;
  margin: 14px 0;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  background: rgba(10, 15, 26, 0.6);
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13.5px;
  text-align: left;
}

.spec-table th,
.spec-table td {
  padding: 10px 14px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.spec-table th {
  background: rgba(255, 255, 255, 0.04);
  color: #ffffff;
  font-weight: 700;
  white-space: nowrap;
}

.spec-table tr:last-child td {
  border-bottom: none;
}

.spec-table .spec-target {
  font-weight: 600;
  color: var(--primary-light);
  white-space: nowrap;
}

.spec-table .spec-min {
  color: #cbd5e1;
}

.spec-table .spec-rec {
  color: var(--emerald-light);
  font-weight: 600;
}

/* FAQ 답변 내부 인라인 팁 박스 */
.faq-inline-notice {
  margin: 12px 0 6px;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 13.5px;
  line-height: 1.6;
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

.faq-inline-notice.green {
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid rgba(16, 185, 129, 0.25);
  color: #a7f3d0;
}

.faq-inline-notice.blue {
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.25);
  color: #bae6fd;
}

.faq-inline-notice.warn {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.25);
  color: #fde68a;
}

/* 8. 글로벌 푸터 (Footer) */
.page-footer {
  margin-top: 80px;
  padding-top: 36px;
  border-top: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-size: 13px;
  line-height: 1.7;
}

.footer-top-row {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 24px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.footer-brand-info h4 {
  color: #ffffff;
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 6px;
}

.footer-links {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--text-sub);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.footer-bottom-copy {
  font-size: 12px;
  color: var(--text-muted);
}

/* 9. 플로팅 탑 이동 버튼 (Back to top) */
.btn-back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-card-solid);
  border: 1px solid var(--border-light);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-base);
  z-index: 99;
}

.btn-back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.btn-back-to-top:hover {
  background: var(--primary);
  border-color: var(--primary-light);
  box-shadow: 0 0 20px var(--primary-glow);
}

/* 10. 반응형 미디어 쿼리 (Responsive Breakdown) */
@media (max-width: 1024px) {
  .sidebar {
    width: 280px;
  }
  .main-content {
    padding: 32px 36px 80px;
  }
}

@media (max-width: 860px) {
  .mobile-topbar {
    display: flex;
  }

  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    transform: translateX(-100%);
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.8);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .sidebar-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 95;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
  }

  .sidebar-backdrop.active {
    opacity: 1;
    visibility: visible;
  }

  .main-content {
    padding: 24px 20px 80px;
  }

  .hero-banner {
    padding: 28px 24px;
  }

  .hero-title {
    font-size: 25px;
  }

  .video-frame-container {
    padding: 16px 16px 12px;
  }

  .card-body-content {
    padding: 14px 18px 24px;
  }

  .faq-answer-inner {
    padding-left: 20px;
  }
}