.page-faq {
  --faq-sidebar-width: 300px;
  --faq-gap: var(--space-xl, 2rem);
  --faq-item-radius: 8px;
  --faq-accent-line: var(--color-accent, #FF6B35);
  --faq-alt-line: var(--color-accent-alt, #00B4D8);
  background-color: var(--color-background, #0A1F3B);
  color: var(--text-primary, #FFFFFF);
  padding: var(--space-lg, 2rem) 0 var(--space-2xl, 4rem);
  font-family: var(--font-body, 'Inter', 'Roboto', sans-serif);
}

.page-faq .container {
  max-width: var(--content-max-width, 1280px);
  margin: 0 auto;
  padding: 0 var(--space-md, 1rem);
}

/* 面包屑 */
.page-faq .breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-xs, 0.25rem);
  font-size: var(--size-data-small, 0.9rem);
  color: var(--text-secondary, #C0C0C0);
  margin-bottom: var(--space-lg, 2rem);
  padding: 0;
  list-style: none;
}
.page-faq .breadcrumb a {
  color: var(--text-secondary, #C0C0C0);
  text-decoration: none;
  transition: color var(--transition-fast, 150ms ease);
}
.page-faq .breadcrumb a:hover,
.page-faq .breadcrumb a:focus-visible {
  color: var(--faq-accent-line);
}
.page-faq .breadcrumb__sep {
  margin: 0 var(--space-xs, 0.25rem);
  color: var(--color-neutral-dark, #C0C0C0);
  user-select: none;
}
.page-faq .breadcrumb [aria-current="page"] {
  color: var(--text-primary, #FFFFFF);
  font-weight: 500;
}

/* 页面标题区 */
.page-faq .faq-header {
  margin-bottom: var(--space-xl, 3rem);
  position: relative;
}
.page-faq .faq-header::after {
  content: '';
  display: block;
  width: 64px;
  height: 4px;
  background: linear-gradient(90deg, var(--faq-accent-line), var(--faq-alt-line));
  margin-top: var(--space-sm, 0.5rem);
  clip-path: polygon(0 0, 100% 0, 94% 100%, 0% 100%);
}
.page-faq .faq-header__title {
  font-family: var(--font-heading, 'Impact', 'Arial Black', sans-serif);
  font-size: var(--size-h1, clamp(2.2rem, 6vw, 3.5rem));
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: -0.5px;
  margin: 0 0 var(--space-sm, 0.5rem);
  color: var(--text-primary, #FFFFFF);
  line-height: 1.1;
}
.page-faq .faq-header__desc {
  font-size: var(--size-body, 1rem);
  color: var(--text-secondary, #C0C0C0);
  max-width: 640px;
  line-height: 1.6;
  margin: 0;
}

/* 主布局：侧边栏 + 内容区 */
.page-faq .faq-layout {
  display: flex;
  flex-direction: column;
  gap: var(--faq-gap);
}

/* 侧边栏（问题目录） */
.page-faq .faq-sidebar {
  background: var(--color-surface, #142B4A);
  border-radius: var(--faq-item-radius);
  padding: var(--space-lg, 2rem);
  position: relative;
  border-left: 4px solid var(--faq-accent-line);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
}
.page-faq .faq-sidebar__heading {
  font-family: var(--font-heading, 'Impact', 'Arial Black', sans-serif);
  font-size: var(--size-h3, 1.2rem);
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--faq-accent-line);
  margin: 0 0 var(--space-md, 1rem);
  padding-bottom: var(--space-sm, 0.5rem);
  border-bottom: 1px solid var(--color-border, #2A4265);
}
.page-faq .faq-sidebar__group {
  margin-bottom: var(--space-md, 1rem);
}
.page-faq .faq-sidebar__group:last-child {
  margin-bottom: 0;
}
.page-faq .faq-sidebar__cat {
  font-family: var(--font-body, 'Inter', 'Roboto', sans-serif);
  font-size: var(--size-data-small, 0.9rem);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--faq-alt-line);
  margin: 0 0 var(--space-xs, 0.25rem);
  padding: 0 0 0 var(--space-sm, 0.5rem);
  border-left: 2px solid var(--faq-alt-line);
  line-height: 1.4;
}
.page-faq .faq-sidebar__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 var(--space-md, 1rem);
}
.page-faq .faq-sidebar__list li {
  margin-bottom: var(--space-xs, 0.25rem);
}
.page-faq .faq-sidebar__link {
  display: block;
  padding: var(--space-xs, 0.25rem) 0;
  color: var(--text-secondary, #C0C0C0);
  text-decoration: none;
  font-size: var(--size-data-small, 0.9rem);
  line-height: 1.5;
  transition: color var(--transition-fast, 150ms ease), padding-left var(--transition-fast, 150ms ease);
  position: relative;
}
.page-faq .faq-sidebar__link::before {
  content: '›';
  position: absolute;
  left: -0.8rem;
  color: var(--faq-accent-line);
  opacity: 0;
  transition: opacity var(--transition-fast, 150ms ease);
}
.page-faq .faq-sidebar__link:hover,
.page-faq .faq-sidebar__link:focus-visible {
  color: var(--text-primary, #FFFFFF);
  padding-left: var(--space-xs, 0.25rem);
}
.page-faq .faq-sidebar__link:hover::before,
.page-faq .faq-sidebar__link:focus-visible::before {
  opacity: 1;
}

/* 内容区（问答详情） */
.page-faq .faq-content {
  flex: 1;
  min-width: 0;
}

/* 分类块 */
.page-faq .faq-category-block {
  margin-bottom: var(--space-xl, 3rem);
}
.page-faq .faq-category-block:last-of-type {
  margin-bottom: var(--space-lg, 2rem);
}
.page-faq .faq-category-block__title {
  font-family: var(--font-heading, 'Impact', 'Arial Black', sans-serif);
  font-size: var(--size-h2, clamp(1.6rem, 4vw, 2.2rem));
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: -0.3px;
  color: var(--text-primary, #FFFFFF);
  margin: 0 0 var(--space-md, 1rem);
  padding: 0 0 var(--space-sm, 0.5rem);
  border-bottom: 2px solid var(--color-border, #2A4265);
  position: relative;
}
.page-faq .faq-category-block__title::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 80px;
  height: 2px;
  background: var(--faq-accent-line);
}

/* 单个问答项 */
.page-faq .faq-item {
  background: var(--color-surface, #142B4A);
  border-radius: var(--faq-item-radius);
  margin-bottom: var(--space-sm, 0.5rem);
  border: 1px solid var(--color-border, #2A4265);
  transition: border-color var(--transition-fast, 150ms ease), box-shadow var(--transition-fast, 150ms ease);
  overflow: hidden;
}
.page-faq .faq-item:target {
  border-color: var(--faq-accent-line);
  box-shadow: 0 0 0 2px rgba(255, 107, 53, 0.2);
}
.page-faq .faq-item__question {
  display: flex;
  align-items: center;
  gap: var(--space-sm, 0.5rem);
  padding: var(--space-md, 1rem) var(--space-md, 1rem);
  cursor: pointer;
  user-select: none;
  outline: none;
  transition: background var(--transition-fast, 150ms ease);
  position: relative;
}
.page-faq .faq-item__question:hover {
  background: rgba(255, 255, 255, 0.03);
}
.page-faq .faq-item__question:focus-visible {
  box-shadow: inset 0 0 0 2px var(--faq-accent-line);
  border-radius: var(--faq-item-radius) var(--faq-item-radius) 0 0;
}
.page-faq .faq-item__num {
  font-family: var(--font-data, 'JetBrains Mono', 'Fira Code', monospace);
  font-size: var(--size-data-small, 0.9rem);
  font-weight: 700;
  color: var(--faq-accent-line);
  min-width: 2rem;
  text-align: right;
  line-height: 1;
  opacity: 0.7;
}
.page-faq .faq-item__qtext {
  flex: 1;
  font-family: var(--font-body, 'Inter', 'Roboto', sans-serif);
  font-size: var(--size-body, 1rem);
  font-weight: 600;
  color: var(--text-primary, #FFFFFF);
  line-height: 1.4;
}
.page-faq .faq-item__icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  position: relative;
  transition: transform var(--transition-base, 250ms ease);
}
.page-faq .faq-item__icon::before,
.page-faq .faq-item__icon::after {
  content: '';
  position: absolute;
  background: var(--faq-accent-line);
  border-radius: 2px;
  transition: transform var(--transition-base, 250ms ease);
}
.page-faq .faq-item__icon::before {
  width: 2px;
  height: 14px;
  top: 3px;
  left: 9px;
}
.page-faq .faq-item__icon::after {
  width: 14px;
  height: 2px;
  top: 9px;
  left: 3px;
}
.page-faq .faq-item__question[aria-expanded="true"] .faq-item__icon::before {
  transform: rotate(90deg);
}
.page-faq .faq-item__answer {
  padding: 0 var(--space-lg, 2rem) var(--space-md, 1rem);
  color: var(--text-secondary, #C0C0C0);
  font-size: var(--size-body, 1rem);
  line-height: 1.7;
  border-top: 1px solid transparent;
  transition: max-height var(--transition-base, 250ms ease), padding var(--transition-base, 250ms ease), border-color var(--transition-base, 250ms ease);
  max-height: 0;
  overflow: hidden;
  padding-top: 0;
  padding-bottom: 0;
  border-color: transparent;
}
.page-faq .faq-item__answer[data-open] {
  max-height: 1200px;
  padding-top: var(--space-md, 1rem);
  padding-bottom: var(--space-md, 1rem);
  border-top-color: var(--color-border, #2A4265);
}
.page-faq .faq-item__answer p {
  margin: 0 0 var(--space-sm, 0.5rem);
}
.page-faq .faq-item__answer p:last-of-type {
  margin-bottom: 0;
}
.page-faq .faq-item__link {
  color: var(--faq-accent-line);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast, 150ms ease);
}
.page-faq .faq-item__link:hover,
.page-faq .faq-item__link:focus-visible {
  color: var(--faq-alt-line);
  text-decoration: underline;
}

/* 答案中的图片 */
.page-faq .faq-item__figure {
  margin: var(--space-md, 1rem) 0;
  max-width: 100%;
}
.page-faq .faq-item__img {
  max-width: 100%;
  height: auto;
  border-radius: var(--corner-cut, 6px);
  border: 1px solid var(--color-border, #2A4265);
  background: var(--color-primary-dark, #061226);
  object-fit: cover;
  display: block;
}
.page-faq .faq-item__figcap {
  font-size: var(--size-data-small, 0.9rem);
  color: var(--text-secondary, #C0C0C0);
  margin-top: var(--space-xs, 0.25rem);
  font-style: italic;
  opacity: 0.8;
}

/* 操作按钮 */
.page-faq .faq-item__actions {
  margin-top: var(--space-sm, 0.5rem);
  display: flex;
  gap: var(--space-sm, 0.5rem);
  flex-wrap: wrap;
}
.page-faq .btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs, 0.25rem);
  padding: 0.4rem 1rem;
  font-family: var(--font-body, 'Inter', 'Roboto', sans-serif);
  font-size: var(--size-data-small, 0.9rem);
  font-weight: 600;
  border: none;
  border-radius: var(--corner-cut, 6px);
  cursor: pointer;
  transition: background var(--transition-fast, 150ms ease), color var(--transition-fast, 150ms ease), transform var(--transition-fast, 150ms ease);
  line-height: 1.4;
}
.page-faq .btn--copy {
  background: var(--faq-accent-line);
  color: var(--text-on-accent, #0A1F3B);
}
.page-faq .btn--copy:hover,
.page-faq .btn--copy:focus-visible {
  background: var(--faq-alt-line);
  color: var(--text-primary, #FFFFFF);
  transform: scale(1.02);
}
.page-faq .btn--copy:active {
  transform: scale(0.97);
}

/* 脚注 */
.page-faq .faq-footnote {
  margin-top: var(--space-lg, 2rem);
  padding: var(--space-md, 1rem);
  background: var(--color-primary-dark, #061226);
  border-radius: var(--faq-item-radius);
  color: var(--text-secondary, #C0C0C0);
  font-size: var(--size-body, 1rem);
  text-align: center;
  border: 1px solid var(--color-border, #2A4265);
}
.page-faq .faq-footnote a {
  color: var(--faq-accent-line);
  text-decoration: none;
  font-weight: 600;
}
.page-faq .faq-footnote a:hover {
  text-decoration: underline;
  color: var(--faq-alt-line);
}

/* ===== 移动端优先，以上为移动端样式 ===== */
/* 桌面端 ≥768px */
@media screen and (min-width: 768px) {
  .page-faq .faq-layout {
    flex-direction: row;
    align-items: flex-start;
  }
  .page-faq .faq-sidebar {
    width: var(--faq-sidebar-width);
    flex-shrink: 0;
    position: sticky;
    top: calc(var(--header-top-height, 48px) + var(--nav-height, 52px) + var(--space-md, 1rem));
    max-height: calc(100vh - var(--header-top-height, 48px) - var(--nav-height, 52px) - var(--space-xl, 3rem));
    overflow-y: auto;
  }
  .page-faq .faq-content {
    flex: 1;
    min-width: 0;
  }
  .page-faq .faq-item__question {
    padding: var(--space-md, 1rem) var(--space-lg, 2rem);
  }
  .page-faq .faq-item__num {
    min-width: 2.5rem;
    font-size: 1rem;
  }
  .page-faq .faq-item__answer {
    padding-left: var(--space-xl, 3rem);
    padding-right: var(--space-xl, 3rem);
  }
  .page-faq .faq-item__img {
    max-width: 480px;
  }
}

/* 桌面宽屏 ≥1024px */
@media screen and (min-width: 1024px) {
  .page-faq {
    padding: var(--space-xl, 3rem) 0 var(--space-2xl, 4rem);
  }
  .page-faq .faq-sidebar {
    --faq-sidebar-width: 320px;
    padding: var(--space-xl, 3rem) var(--space-lg, 2rem);
  }
  .page-faq .faq-header__title {
    font-size: var(--size-h1, clamp(2.2rem, 6vw, 3.5rem));
  }
  .page-faq .faq-item__question {
    padding: var(--space-lg, 2rem) var(--space-xl, 3rem);
  }
  .page-faq .faq-item__answer {
    padding: 0 var(--space-xl, 3rem) var(--space-lg, 2rem);
  }
  .page-faq .faq-item__answer[data-open] {
    padding-top: var(--space-md, 1rem);
    padding-bottom: var(--space-md, 1rem);
  }
}

/* 确保锚点跳转时目标可见 */
.page-faq .faq-item:target {
  scroll-margin-top: calc(var(--header-top-height, 48px) + var(--nav-height, 52px) + var(--space-lg, 2rem));
}

/* 无JS降级：所有答案默认显示第一项，其余通过data-open控制 */
/* 用户无JS时data-open不会动态变化，因此只有第一项展开，其余折叠 — 但内容仍可通过点击锚点定位阅读 */
/* 为提升无JS体验，让所有答案默认展开（data-open均存在） */
/* 但由于手风琴交互依赖JS，静态时全部展开确保内容可读 */
/* 这里通过属性选择器保证data-open的项正常显示 */
.page-faq .faq-item__answer[data-open] {
  max-height: 1200px;
  padding-top: var(--space-md, 1rem);
  padding-bottom: var(--space-md, 1rem);
  border-top-color: var(--color-border, #2A4265);
}
.page-faq .faq-item__answer:not([data-open]) {
  max-height: 0;
  padding-top: 0;
  padding-bottom: 0;
  border-top-color: transparent;
}

/* 数据高亮辅助 */
.page-faq .faq-item__data-highlight {
  font-family: var(--font-data, 'JetBrains Mono', 'Fira Code', monospace);
  color: var(--faq-alt-line);
  font-weight: 500;
}

/* 装饰性斜线（杂志感） */
.page-faq .faq-category-block__title {
  position: relative;
  overflow: hidden;
}
.page-faq .faq-category-block__title::before {
  content: '';
  position: absolute;
  right: 0;
  top: 50%;
  width: 120px;
  height: 1px;
  background: linear-gradient(90deg, var(--color-border, #2A4265), transparent);
  transform: translateY(-50%);
}

/* 侧边栏分类装饰 */
.page-faq .faq-sidebar__cat {
  position: relative;
  padding-left: var(--space-md, 1rem);
}
.page-faq .faq-sidebar__cat::before {
  content: '';
  position: absolute;
  left: 0;
  top: 2px;
  bottom: 2px;
  width: 2px;
  background: var(--faq-alt-line);
  border-radius: 1px;
}