.page-faq {
  --faq-border-wine: var(--color-wine, #7B241C);
  --faq-border-gold: var(--color-gold, #D4AF37);
  --faq-bg-card: var(--color-white, #FFFFFF);
  --faq-bg-tab-active: var(--color-primary, #E60012);
  --faq-text-dark: var(--color-black, #1A1A1A);
  --faq-text-muted: #555555;
  --faq-radius: 6px;
  --faq-gap: var(--space-md, 1rem);
  --faq-panel-max: 840px;

  display: block;
  max-width: var(--max-width, 1200px);
  margin: 0 auto;
  padding: var(--space-md, 1rem) var(--space-md, 1rem) var(--space-xl, 3rem);
  font-family: var(--font-body, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif);
  color: var(--faq-text-dark);
  background-color: var(--color-light-gray, #F2F2F2);
  line-height: 1.6;
}

/* --- 面包屑 --- */
.faq-breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 300;
  color: var(--faq-text-muted);
  margin-bottom: var(--space-lg, 2rem);
  padding-bottom: var(--space-sm, 0.5rem);
  border-bottom: 1px solid rgba(0,0,0,0.08);
}
.faq-breadcrumb-link {
  color: var(--faq-text-muted);
  text-decoration: none;
  transition: color var(--transition-fast, 0.2s ease);
}
.faq-breadcrumb-link:hover,
.faq-breadcrumb-link:focus-visible {
  color: var(--color-primary, #E60012);
}
.faq-breadcrumb-sep {
  color: var(--faq-text-muted);
  font-weight: 200;
}
.faq-breadcrumb-current {
  color: var(--faq-text-dark);
  font-weight: 400;
}

/* --- 页面标题区 --- */
.faq-header {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  margin-bottom: var(--space-xl, 3rem);
  position: relative;
}
.faq-header-icon {
  width: 100px;
  height: 100px;
  object-fit: contain;
  margin-bottom: var(--space-md, 1rem);
  opacity: 0.9;
  filter: drop-shadow(0 4px 12px rgba(212, 175, 55, 0.25));
}
.faq-heading {
  font-family: var(--font-headline, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif);
  font-weight: 200;
  font-size: clamp(2rem, 8vw, 3.6rem);
  letter-spacing: 0.04em;
  color: var(--color-primary, #E60012);
  margin: 0 0 var(--space-sm, 0.5rem);
  line-height: 1.15;
}
.faq-subtitle {
  font-size: clamp(0.95rem, 3vw, 1.15rem);
  font-weight: 300;
  color: var(--faq-text-muted);
  max-width: 620px;
  margin: 0 auto;
}

/* --- 浏览器容器 --- */
.faq-browser {
  display: block;
  margin-bottom: var(--space-xl, 3rem);
}

/* --- 隐藏 radio --- */
.faq-cat-radio {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
  pointer-events: none;
}

/* --- 分类标签 --- */
.faq-tabs {
  display: flex;
  flex-wrap: nowrap;
  gap: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--color-gold, #D4AF37) transparent;
  margin-bottom: var(--space-lg, 2rem);
  border-bottom: 2px solid rgba(0,0,0,0.06);
  padding-bottom: 0;
}
.faq-tabs::-webkit-scrollbar {
  height: 4px;
}
.faq-tabs::-webkit-scrollbar-thumb {
  background-color: var(--color-gold, #D4AF37);
  border-radius: 4px;
}
.faq-tab {
  flex: 0 0 auto;
  padding: var(--space-sm, 0.5rem) var(--space-lg, 2rem);
  font-size: 0.95rem;
  font-weight: 400;
  color: var(--faq-text-muted);
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  cursor: pointer;
  transition: color var(--transition-fast, 0.2s ease), border-color var(--transition-fast, 0.2s ease), background-color var(--transition-fast, 0.2s ease);
  white-space: nowrap;
  user-select: none;
  text-align: center;
}
.faq-tab:hover {
  color: var(--color-primary, #E60012);
  background-color: rgba(230, 0, 18, 0.04);
}

/* radio 选中态：对应标签高亮 */
#faq-cat-download:checked ~ .faq-tabs label[for="faq-cat-download"],
#faq-cat-guide:checked ~ .faq-tabs label[for="faq-cat-guide"],
#faq-cat-data:checked ~ .faq-tabs label[for="faq-cat-data"],
#faq-cat-feedback:checked ~ .faq-tabs label[for="faq-cat-feedback"] {
  color: var(--faq-bg-tab-active);
  border-bottom-color: var(--faq-bg-tab-active);
  font-weight: 600;
}

/* --- 面板容器 --- */
.faq-panels {
  display: block;
  position: relative;
}

/* --- 单个面板（默认隐藏） --- */
.faq-panel {
  display: none;
  animation: faq-fade-in 0.35s ease both;
}
@keyframes faq-fade-in {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* radio 选中态：显示对应面板 */
#faq-cat-download:checked ~ .faq-panels #panel-download,
#faq-cat-guide:checked ~ .faq-panels #panel-guide,
#faq-cat-data:checked ~ .faq-panels #panel-data,
#faq-cat-feedback:checked ~ .faq-panels #panel-feedback {
  display: block;
}

/* --- 面板标题 --- */
.faq-panel-heading {
  font-family: var(--font-headline, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif);
  font-weight: 300;
  font-size: 1.5rem;
  color: var(--color-primary, #E60012);
  margin: 0 0 var(--space-md, 1rem);
  padding-bottom: var(--space-sm, 0.5rem);
  border-bottom: 2px solid var(--faq-border-wine);
  display: inline-block;
}

/* --- 单个问题卡片（折叠） --- */
.faq-item {
  display: block;
  background: var(--faq-bg-card);
  border: 1px solid var(--faq-border-wine);
  border-left: 5px solid var(--faq-border-wine);
  border-radius: var(--faq-radius);
  margin-bottom: var(--space-md, 1rem);
  overflow: hidden;
  transition: border-color var(--transition-fast, 0.2s ease), box-shadow var(--transition-fast, 0.2s ease);
}
.faq-item:hover {
  border-color: var(--color-gold, #D4AF37);
  box-shadow: 0 4px 20px rgba(212, 175, 55, 0.12);
}

/* --- 问题标题（summary） --- */
.faq-question {
  display: block;
  padding: var(--space-md, 1rem) var(--space-lg, 2rem);
  font-size: 1rem;
  font-weight: 500;
  color: var(--faq-text-dark);
  cursor: pointer;
  position: relative;
  user-select: none;
  transition: background-color var(--transition-fast, 0.2s ease);
  list-style: none;
}
.faq-question::-webkit-details-marker {
  display: none;
}
.faq-question::marker {
  display: none;
  content: "";
}
.faq-question::after {
  content: "+";
  position: absolute;
  right: var(--space-md, 1rem);
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.4rem;
  font-weight: 200;
  color: var(--faq-border-wine);
  transition: transform var(--transition-fast, 0.2s ease), color var(--transition-fast, 0.2s ease);
}
details[open] .faq-question::after {
  content: "−";
  transform: translateY(-50%) rotate(0deg);
  color: var(--color-primary, #E60012);
}
.faq-question:hover {
  background-color: rgba(230, 0, 18, 0.03);
}

/* --- 答案内容 --- */
.faq-answer {
  padding: 0 var(--space-lg, 2rem) var(--space-md, 1rem);
  font-size: 0.95rem;
  font-weight: 300;
  color: var(--faq-text-muted);
  line-height: 1.7;
}
.faq-answer p {
  margin: 0 0 var(--space-sm, 0.5rem);
}
.faq-answer p:last-child {
  margin-bottom: 0;
}

/* --- 数据示意图 --- */
.faq-data-chart {
  display: block;
  max-width: 100%;
  height: auto;
  margin: var(--space-lg, 2rem) auto 0;
  border-radius: var(--faq-radius);
  object-fit: cover;
  border: 1px solid rgba(0,0,0,0.06);
  box-shadow: 0 4px 24px rgba(0,0,0,0.06);
}

/* --- 联系客服区域 --- */
.faq-contact {
  margin-top: var(--space-xl, 3rem);
  padding: var(--space-lg, 2rem) var(--space-md, 1rem);
  background: var(--color-black, #1A1A1A);
  border-radius: var(--faq-radius);
  text-align: center;
  color: var(--color-white, #FFFFFF);
}
.faq-contact-heading {
  font-family: var(--font-headline, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif);
  font-weight: 200;
  font-size: clamp(1.6rem, 5vw, 2.4rem);
  margin: 0 0 var(--space-sm, 0.5rem);
  letter-spacing: 0.03em;
}
.faq-contact-desc {
  font-weight: 300;
  font-size: 1rem;
  color: rgba(255,255,255,0.7);
  max-width: 520px;
  margin: 0 auto var(--space-lg, 2rem);
  line-height: 1.6;
}
.faq-contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm, 0.5rem);
  margin-bottom: var(--space-lg, 2rem);
  align-items: center;
}
.faq-contact-item {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.95rem;
}
.faq-contact-label {
  font-weight: 400;
  color: var(--color-gold, #D4AF37);
}
.faq-contact-value {
  font-weight: 300;
  color: rgba(255,255,255,0.9);
}
.faq-contact-value a {
  color: rgba(255,255,255,0.9);
  text-decoration: none;
  transition: color var(--transition-fast, 0.2s ease);
}
.faq-contact-value a:hover,
.faq-contact-value a:focus-visible {
  color: var(--color-gold, #D4AF37);
}
.faq-contact-btn {
  display: inline-block;
  padding: var(--space-sm, 0.5rem) var(--space-lg, 2rem);
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-black, #1A1A1A);
  background: var(--color-gold, #D4AF37);
  border-radius: 999px;
  text-decoration: none;
  transition: background var(--transition-fast, 0.2s ease), transform var(--transition-fast, 0.2s ease);
}
.faq-contact-btn:hover,
.faq-contact-btn:focus-visible {
  background: #c9a227;
  transform: scale(1.02);
}

/* --- 桌面端：两列布局（标签固定左侧） --- */
@media (min-width: 768px) {
  .page-faq {
    padding: var(--space-lg, 2rem) var(--space-xl, 3rem) var(--space-xl, 3rem);
  }

  .faq-browser {
    display: flex;
    gap: var(--space-xl, 3rem);
    align-items: flex-start;
  }

  .faq-tabs {
    flex: 0 0 160px;
    flex-direction: column;
    overflow-x: visible;
    border-bottom: none;
    border-right: 2px solid rgba(0,0,0,0.06);
    padding-right: var(--space-md, 1rem);
    margin-bottom: 0;
    position: sticky;
    top: calc(var(--header-top-height, 56px) + var(--space-md, 1rem));
    scrollbar-width: none;
  }
  .faq-tabs::-webkit-scrollbar {
    display: none;
  }

  .faq-tab {
    flex: 0 0 auto;
    padding: var(--space-sm, 0.5rem) var(--space-md, 1rem);
    border-bottom: none;
    border-right: 3px solid transparent;
    text-align: left;
    font-size: 0.95rem;
  }
  .faq-tab:hover {
    background-color: rgba(230, 0, 18, 0.04);
  }

  /* 桌面标签选中态改为右侧边框 */
  #faq-cat-download:checked ~ .faq-tabs label[for="faq-cat-download"],
  #faq-cat-guide:checked ~ .faq-tabs label[for="faq-cat-guide"],
  #faq-cat-data:checked ~ .faq-tabs label[for="faq-cat-data"],
  #faq-cat-feedback:checked ~ .faq-tabs label[for="faq-cat-feedback"] {
    border-bottom-color: transparent;
    border-right-color: var(--faq-bg-tab-active);
    background-color: rgba(230, 0, 18, 0.05);
  }

  .faq-panels {
    flex: 1;
    min-width: 0;
  }

  .faq-panel {
    max-width: var(--faq-panel-max);
  }

  .faq-contact-info {
    flex-direction: row;
    justify-content: center;
    gap: var(--space-lg, 2rem);
  }
}

/* --- 大桌面端优化 --- */
@media (min-width: 1200px) {
  .page-faq {
    padding: var(--space-xl, 3rem) var(--space-xl, 3rem) var(--space-xl, 3rem);
  }
  .faq-header-icon {
    width: 120px;
    height: 120px;
  }
  .faq-heading {
    font-size: 4rem;
  }
  .faq-tabs {
    flex-basis: 180px;
  }
  .faq-tab {
    font-size: 1rem;
    padding: var(--space-md, 1rem) var(--space-md, 1rem);
  }
  .faq-panel-heading {
    font-size: 1.75rem;
  }
  .faq-question {
    font-size: 1.05rem;
  }
}