/* ===== 帮助中心页面专属样式 ===== */
.page-faq {
  --faq-accent: var(--color-electric-blue, #00D4FF);
  --faq-accent-alt: var(--color-fluo-green, #39FF14);
  --faq-card-bg: var(--color-deep-gray, #1A1F2E);
  --faq-card-border: rgba(192, 198, 217, 0.15);
  --faq-text-muted: var(--color-metal-silver, #C0C6D9);
  --faq-radius: var(--border-radius, 6px);
  --faq-transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --faq-paper-shadow: 0 2px 0 rgba(0, 212, 255, 0.08), 0 4px 0 rgba(0, 212, 255, 0.04), 0 8px 24px rgba(0, 0, 0, 0.4);
  --faq-max-width: min(var(--site-max-width, 1200px), 100% - 2rem);

  background-color: var(--color-dark-night, #0A0F1A);
  color: var(--faq-text-muted);
  padding: calc(var(--header-height, 60px) + 1rem) 1rem 3rem;
  min-height: 100vh;
  font: var(--font-body);
}

/* 容器 */
.page-faq .container {
  max-width: var(--faq-max-width);
  margin: 0 auto;
  width: 100%;
}

/* 面包屑 */
.page-faq .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--faq-text-muted);
  margin-bottom: 1.5rem;
  opacity: 0.7;
}
.page-faq .breadcrumb a {
  color: var(--faq-accent);
  text-decoration: none;
  transition: color var(--faq-transition);
}
.page-faq .breadcrumb a:hover,
.page-faq .breadcrumb a:focus {
  color: var(--faq-accent-alt);
  text-decoration: underline;
}
.page-faq .breadcrumb-sep {
  color: var(--faq-text-muted);
  opacity: 0.4;
}

/* 页面头部 */
.page-faq .page-header {
  margin-bottom: 2.5rem;
  border-left: 4px solid var(--faq-accent);
  padding-left: 1.2rem;
}
.page-faq .page-title {
  font: var(--font-heading);
  font-size: clamp(1.8rem, 4.5vw, 2.8rem);
  color: var(--color-white, #FFFFFF);
  margin: 0 0 0.5rem;
  letter-spacing: -0.02em;
  line-height: 1.1;
}
.page-faq .page-description {
  font-size: clamp(0.95rem, 1.4vw, 1.1rem);
  color: var(--faq-text-muted);
  max-width: 640px;
  margin: 0;
  line-height: 1.6;
}

/* ===== 标签页 ===== */
.page-faq .faq-tabs {
  margin-bottom: 2.5rem;
}

/* 标签导航 */
.page-faq .tab-nav {
  display: flex;
  gap: 0.25rem;
  border-bottom: 1px solid var(--faq-card-border);
  padding-bottom: 0;
  margin-bottom: 2rem;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--faq-accent) transparent;
}
.page-faq .tab-nav::-webkit-scrollbar {
  height: 3px;
}
.page-faq .tab-nav::-webkit-scrollbar-thumb {
  background-color: var(--faq-accent);
  border-radius: 6px;
}

.page-faq .tab-btn {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.75rem 1.2rem 0.9rem;
  font: var(--font-heading);
  font-size: 0.95rem;
  color: var(--faq-text-muted);
  background: transparent;
  border: none;
  border-bottom: 3px solid transparent;
  cursor: pointer;
  transition: color var(--faq-transition), border-color var(--faq-transition), background var(--faq-transition);
  position: relative;
  white-space: nowrap;
}
.page-faq .tab-btn:hover,
.page-faq .tab-btn:focus {
  color: var(--color-white);
  background: rgba(0, 212, 255, 0.04);
  outline: none;
}
.page-faq .tab-btn:focus-visible {
  outline: 2px solid var(--faq-accent);
  outline-offset: -2px;
  border-radius: 2px;
}
.page-faq .tab-btn[aria-selected="true"] {
  color: var(--faq-accent);
  border-bottom-color: var(--faq-accent);
}
.page-faq .tab-btn[aria-selected="true"] .tab-count {
  background: var(--faq-accent);
  color: var(--color-dark-night, #0A0F1A);
}
.page-faq .tab-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.5rem;
  height: 1.5rem;
  padding: 0 0.4rem;
  font-size: 0.7rem;
  font-weight: 700;
  border-radius: 999px;
  background: rgba(192, 198, 217, 0.12);
  color: var(--faq-text-muted);
  transition: background var(--faq-transition), color var(--faq-transition);
}
.page-faq .tab-label {
  font-weight: 700;
}

/* 标签面板 */
.page-faq .tab-panel {
  display: block;
  animation: faq-fade-in 0.35s ease-out;
}
.page-faq .tab-panel[hidden] {
  display: none;
  animation: none;
}

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

/* 面板图片 */
.page-faq .panel-image-wrap {
  position: relative;
  margin-bottom: 2rem;
  border-radius: var(--faq-radius);
  overflow: hidden;
  box-shadow: var(--faq-paper-shadow);
  background: var(--faq-card-bg);
  max-width: 100%;
}
.page-faq .panel-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: attr(width) / attr(height);
  background: var(--color-dark-night);
}
.page-faq .image-caption {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 0.6rem 1rem;
  font-size: 0.78rem;
  color: var(--color-white);
  background: linear-gradient(transparent, rgba(10, 15, 26, 0.85));
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  pointer-events: none;
}

/* ===== 问题列表 ===== */
.page-faq .faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* 单个问题卡片 - 纸张叠层效果 */
.page-faq .faq-item {
  background: var(--faq-card-bg);
  border-radius: var(--faq-radius);
  box-shadow: var(--faq-paper-shadow);
  border: 1px solid var(--faq-card-border);
  transition: box-shadow var(--faq-transition), transform var(--faq-transition);
  transform: translateY(0);
  overflow: hidden;
}
.page-faq .faq-item:hover {
  box-shadow: 0 4px 0 rgba(0, 212, 255, 0.1), 0 8px 0 rgba(0, 212, 255, 0.05), 0 12px 32px rgba(0, 0, 0, 0.5);
  transform: translateY(-1px);
}
.page-faq .faq-item[data-open="true"] {
  box-shadow: 0 3px 0 rgba(0, 212, 255, 0.12), 0 6px 0 rgba(0, 212, 255, 0.06), 0 10px 28px rgba(0, 0, 0, 0.45);
  border-color: rgba(0, 212, 255, 0.2);
}

/* 印刷边框装饰 - 伪元素实现四角标记 */
.page-faq .faq-item::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 12px;
  height: 12px;
  border-top: 2px solid var(--faq-accent);
  border-left: 2px solid var(--faq-accent);
  opacity: 0.3;
  transition: opacity var(--faq-transition);
  pointer-events: none;
}
.page-faq .faq-item::after {
  content: "";
  position: absolute;
  bottom: -1px;
  right: -1px;
  width: 12px;
  height: 12px;
  border-bottom: 2px solid var(--faq-accent);
  border-right: 2px solid var(--faq-accent);
  opacity: 0.3;
  transition: opacity var(--faq-transition);
  pointer-events: none;
}
.page-faq .faq-item:hover::before,
.page-faq .faq-item:hover::after {
  opacity: 0.7;
}

/* 问题按钮 */
.page-faq .faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  padding: 1.2rem 1.4rem;
  font: var(--font-heading);
  font-size: clamp(0.95rem, 1.2vw, 1.05rem);
  color: var(--color-white);
  background: transparent;
  border: none;
  cursor: pointer;
  text-align: left;
  transition: background var(--faq-transition), color var(--faq-transition);
  position: relative;
  z-index: 1;
  line-height: 1.3;
}
.page-faq .faq-question:hover,
.page-faq .faq-question:focus {
  background: rgba(0, 212, 255, 0.03);
  outline: none;
}
.page-faq .faq-question:focus-visible {
  outline: 2px solid var(--faq-accent);
  outline-offset: -4px;
  border-radius: 4px;
}
.page-faq .faq-question .question-text {
  flex: 1;
  font-weight: 700;
}
.page-faq .faq-icon {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.6rem;
  height: 1.6rem;
  color: var(--faq-accent);
  transition: transform var(--faq-transition), color var(--faq-transition);
}
.page-faq .faq-icon svg {
  width: 100%;
  height: 100%;
  transition: transform var(--faq-transition);
}
.page-faq .faq-item[data-open="true"] .faq-icon svg {
  transform: rotate(45deg);
}
.page-faq .faq-item[data-open="true"] .faq-icon {
  color: var(--faq-accent-alt);
}

/* 答案区域 */
.page-faq .faq-answer {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows var(--faq-transition);
  padding: 0 1.4rem;
  border-top: 1px solid transparent;
}
.page-faq .faq-item[data-open="true"] .faq-answer {
  grid-template-rows: 1fr;
  border-top-color: var(--faq-card-border);
}
.page-faq .faq-answer > * {
  overflow: hidden;
}
.page-faq .faq-answer p {
  margin: 0;
  padding: 0.8rem 0 1.2rem;
  font-size: clamp(0.88rem, 1.1vw, 0.95rem);
  line-height: 1.7;
  color: var(--faq-text-muted);
}
.page-faq .faq-answer a {
  color: var(--faq-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-thickness: 1px;
  transition: color var(--faq-transition);
}
.page-faq .faq-answer a:hover,
.page-faq .faq-answer a:focus {
  color: var(--faq-accent-alt);
  text-decoration-thickness: 2px;
}

/* ===== 底部提示 ===== */
.page-faq .faq-footer-note {
  margin-top: 2.5rem;
  padding: 1.2rem 1.6rem;
  background: var(--faq-card-bg);
  border: 1px solid var(--faq-card-border);
  border-radius: var(--faq-radius);
  font-size: 0.92rem;
  line-height: 1.6;
  color: var(--faq-text-muted);
  position: relative;
}
.page-faq .faq-footer-note p {
  margin: 0;
}
.page-faq .faq-footer-note a {
  color: var(--faq-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  font-weight: 600;
}
.page-faq .faq-footer-note a:hover {
  color: var(--faq-accent-alt);
}

/* 应用 bracket-box 印刷边框增强 */
.page-faq .bracket-box {
  position: relative;
  box-shadow: inset 0 0 0 1px rgba(192, 198, 217, 0.08), var(--faq-paper-shadow);
}

/* ===== 响应式 - 移动端优先 ===== */

/* 从 640px 起调整 */
@media (min-width: 640px) {
  .page-faq {
    padding: calc(var(--header-height, 60px) + 2rem) 2rem 4rem;
  }
  .page-faq .page-header {
    padding-left: 1.6rem;
    margin-bottom: 3rem;
  }
  .page-faq .tab-btn {
    padding: 0.85rem 1.6rem 1rem;
    font-size: 1rem;
  }
  .page-faq .faq-question {
    padding: 1.3rem 1.6rem;
    font-size: 1rem;
  }
  .page-faq .faq-answer {
    padding: 0 1.6rem;
  }
  .page-faq .faq-answer p {
    padding: 0.6rem 0 1.2rem;
  }
  .page-faq .panel-image-wrap {
    max-width: 90%;
  }
}

/* 从 900px 起两列问题布局 */
@media (min-width: 900px) {
  .page-faq .faq-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.2rem;
  }
  .page-faq .faq-item {
    break-inside: avoid;
  }
  /* 使最后一项占满宽度（如果奇数项） */
  .page-faq .faq-list > .faq-item:last-child:nth-child(odd) {
    grid-column: 1 / -1;
    max-width: calc(50% - 0.6rem);
  }

  /* 面板图片在较宽时限制尺寸并增加视觉权重 */
  .page-faq .panel-image-wrap {
    max-width: 75%;
    margin-left: 0;
  }
  .page-faq .panel-img {
    max-height: 320px;
    object-position: center 20%;
  }

  .page-faq .page-description {
    font-size: 1.1rem;
  }
  .page-faq .tab-nav {
    gap: 0.5rem;
  }
  .page-faq .tab-btn {
    padding: 0.9rem 2rem 1.1rem;
    font-size: 1.05rem;
  }
  .page-faq .faq-footer-note {
    display: flex;
    justify-content: center;
    text-align: center;
    padding: 1.6rem 2rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
  }
}

/* 从 1200px 起固定布局宽度，增加留白 */
@media (min-width: 1200px) {
  .page-faq {
    padding: calc(var(--header-height, 60px) + 3rem) 2rem 5rem;
  }
  .page-faq .container {
    max-width: var(--site-max-width, 1200px);
  }
  .page-faq .page-header {
    padding-left: 2rem;
    border-left-width: 5px;
  }
  .page-faq .page-title {
    font-size: 2.8rem;
  }
  .page-faq .tab-panel {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    align-items: start;
  }
  .page-faq .tab-panel .panel-image-wrap {
    grid-row: 1;
    grid-column: 1;
    max-width: 100%;
    margin-bottom: 0;
    position: sticky;
    top: calc(var(--header-height, 60px) + 2rem);
  }
  .page-faq .tab-panel .faq-list {
    grid-row: 1;
    grid-column: 2;
  }
  /* 数据与更新面板只有问题列表，无需分栏 */
  .page-faq .tab-panel[data-tab-id="data"] {
    display: block;
  }
  .page-faq .tab-panel[data-tab-id="data"] .faq-list {
    grid-template-columns: 1fr 1fr;
  }
  .page-faq .faq-footer-note {
    margin-top: 3rem;
  }
}

/* 窄屏安全间距 */
@media (max-width: 400px) {
  .page-faq {
    padding-left: 0.75rem;
    padding-right: 0.75rem;
  }
  .page-faq .faq-question {
    padding: 1rem 1rem;
    font-size: 0.9rem;
  }
  .page-faq .faq-answer {
    padding: 0 1rem;
  }
  .page-faq .faq-answer p {
    font-size: 0.85rem;
  }
  .page-faq .tab-btn {
    padding: 0.6rem 0.9rem 0.75rem;
    font-size: 0.85rem;
  }
  .page-faq .tab-count {
    min-width: 1.2rem;
    height: 1.2rem;
    font-size: 0.6rem;
  }
  .page-faq .breadcrumb {
    font-size: 0.78rem;
  }
  .page-faq .page-title {
    font-size: 1.5rem;
  }
  .page-faq .page-description {
    font-size: 0.88rem;
  }
}

/* ===== 动效：悬停卡片额外纸层位移 ===== */
@media (hover: hover) {
  .page-faq .faq-item[data-open="true"] {
    transform: translateY(-2px);
  }
  .page-faq .faq-item:hover .faq-question {
    background: rgba(0, 212, 255, 0.035);
  }
}

/* ===== 印刷边框增强（bracket-box 复用） ===== */
.page-faq .bracket-box::before,
.page-faq .bracket-box::after {
  content: "";
  position: absolute;
  width: 20px;
  height: 20px;
  pointer-events: none;
  opacity: 0.15;
}
.page-faq .bracket-box::before {
  top: -1px;
  left: -1px;
  border-top: 2px solid var(--faq-accent);
  border-left: 2px solid var(--faq-accent);
}
.page-faq .bracket-box::after {
  bottom: -1px;
  right: -1px;
  border-bottom: 2px solid var(--faq-accent);
  border-right: 2px solid var(--faq-accent);
}

/* 减少 motion 时禁用动画 */
@media (prefers-reduced-motion: reduce) {
  .page-faq .tab-panel {
    animation: none;
  }
  .page-faq .faq-answer {
    transition: none;
  }
  .page-faq .faq-item,
  .page-faq .faq-icon svg {
    transition: none;
  }
  .page-faq .faq-item:hover {
    transform: none;
  }
}