/* ===== 帮助中心 · page-faq ===== */

/* 页面基础与主题背景 */
.page-faq {
  --faq-radius-lg: 24px;
  --faq-radius-md: 18px;
  padding-bottom: 88px;
  background: linear-gradient(180deg, var(--space-bg), var(--space-bg-2) 100%);
}

/* 标题区 */
.page-faq .faq-hero {
  position: relative;
  padding: calc(var(--header-h) + 44px) 0 52px;
  overflow: hidden;
  background:
    radial-gradient(640px 360px at 90% -10%, rgba(0, 229, 255, 0.18), transparent 65%),
    linear-gradient(rgba(0, 229, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.05) 1px, transparent 1px),
    linear-gradient(160deg, #0c1533 0%, var(--space-bg) 50%, var(--space-bg-2) 100%);
  background-size: auto, 44px 44px, 44px 44px, auto;
}
.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  right: -120px;
  bottom: -160px;
  width: 380px;
  height: 380px;
  border-radius: 50%;
  border: 1px solid rgba(0, 255, 163, 0.2);
  box-shadow: 0 0 0 36px rgba(0, 255, 163, 0.04), 0 0 0 72px rgba(0, 255, 163, 0.02);
  pointer-events: none;
}
.page-faq .faq-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 36px;
  align-items: center;
}
.page-faq .faq-hero-copy .kicker {
  margin-bottom: 10px;
}
.page-faq .faq-hero-copy .page-title {
  margin: 10px 0 16px;
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1.22;
  letter-spacing: -0.01em;
}
.page-faq .faq-hero-copy .page-intro {
  max-width: 640px;
  color: var(--muted-blue);
  font-size: 16px;
  line-height: 1.75;
}
.page-faq .faq-hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 28px;
}
.page-faq .faq-stat-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 104px;
  padding: 14px 18px;
  background: rgba(26, 36, 64, 0.75);
  border: 1px solid rgba(174, 182, 194, 0.2);
  border-radius: var(--faq-radius-md);
}
.page-faq .faq-stat-item .metric-value {
  color: var(--neon-green);
  font-size: 26px;
  line-height: 1.1;
}
.page-faq .faq-stat-label {
  color: var(--muted-blue);
  font-size: 13px;
}
.page-faq .faq-hero-visual {
  display: flex;
  justify-content: center;
}
.page-faq .faq-hero-img {
  width: 100%;
  max-width: 480px;
  height: auto;
  border-radius: var(--faq-radius-lg);
  border: 1px solid rgba(0, 229, 255, 0.28);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.35);
}

/* 帮助主区域 */
.page-faq .faq-main {
  position: relative;
  padding: 64px 0 20px;
}
.page-faq .faq-shell {
  position: relative;
}
.page-faq .faq-filter-input {
  position: absolute;
  top: 0;
  left: 0;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}
.page-faq .faq-layout {
  display: grid;
  gap: 40px;
  align-items: start;
}

/* 左侧分类索引 */
.page-faq .faq-index {
  position: relative;
  padding: 24px 20px;
  background: rgba(16, 27, 58, 0.8);
  border: 1px solid rgba(174, 182, 194, 0.18);
  border-radius: var(--faq-radius-lg);
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.18);
}
.page-faq .faq-index .kicker {
  margin-bottom: 8px;
}
.page-faq .faq-index .section-title {
  margin-bottom: 18px;
  font-size: 22px;
}
.page-faq .faq-cat-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.page-faq .faq-cat-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1px solid rgba(174, 182, 194, 0.32);
  border-radius: 999px;
  color: var(--muted-blue);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  user-select: none;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}
.page-faq .faq-cat-tag:hover {
  border-color: var(--neon-green);
  color: var(--near-white);
  transform: translateY(-2px);
}
.page-faq .faq-cat-count {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--metal-silver);
}
.page-faq .faq-index-note {
  margin-top: 22px;
  padding-top: 22px;
  border-top: 1px solid rgba(174, 182, 194, 0.16);
}
.page-faq .faq-index-img {
  width: 100%;
  max-width: 420px;
  height: auto;
  border-radius: 16px;
  border: 1px solid rgba(0, 229, 255, 0.18);
}
.page-faq .faq-index-note-text {
  margin-top: 12px;
  color: var(--muted-blue);
  font-size: 14px;
  line-height: 1.7;
}

/* 右侧问题列表 */
.page-faq .faq-list {
  min-width: 0;
}
.page-faq .faq-list-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 20px;
}
.page-faq .faq-list-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--near-white);
}
.page-faq .faq-list-hint {
  color: var(--muted-blue);
  font-size: 13px;
}

/* 折叠项 */
.page-faq .faq-item {
  margin-bottom: 14px;
  background: var(--space-bg-2);
  border: 1px solid rgba(174, 182, 194, 0.2);
  border-radius: var(--faq-radius-md);
  transition: border-color 0.25s ease, background 0.25s ease;
}
.page-faq .faq-item[open] {
  border-color: rgba(0, 255, 163, 0.55);
  background: rgba(16, 27, 58, 0.92);
}
.page-faq .faq-item summary {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 18px;
  list-style: none;
  cursor: pointer;
  color: var(--near-white);
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  border-radius: var(--faq-radius-md);
}
.page-faq .faq-item summary::-webkit-details-marker {
  display: none;
}
.page-faq .faq-item summary::before {
  content: "Q";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 28px;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: rgba(0, 255, 163, 0.12);
  color: var(--neon-green);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
}
.page-faq .faq-item summary::after {
  content: "+";
  margin-left: auto;
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--neon-cyan);
  transition: transform 0.25s ease;
}
.page-faq .faq-item[open] summary::after {
  transform: rotate(45deg);
}
.page-faq .faq-answer {
  padding: 0 18px 20px;
  color: var(--muted-blue);
  font-size: 15px;
  line-height: 1.75;
}
.page-faq .faq-answer p {
  margin: 0;
}
.page-faq .faq-answer a {
  color: var(--neon-green);
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* 筛选：仅显示当前分类 */
.page-faq #cat-account:checked ~ .faq-layout .faq-item:not(.cat-account),
.page-faq #cat-sync:checked ~ .faq-layout .faq-item:not(.cat-sync),
.page-faq #cat-version:checked ~ .faq-layout .faq-item:not(.cat-version),
.page-faq #cat-nav:checked ~ .faq-layout .faq-item:not(.cat-nav),
.page-faq #cat-data:checked ~ .faq-layout .faq-item:not(.cat-data),
.page-faq #cat-support:checked ~ .faq-layout .faq-item:not(.cat-support) {
  display: none;
}

/* 分类选中态 */
.page-faq .faq-shell:has(#cat-account:checked) label[for="cat-account"],
.page-faq .faq-shell:has(#cat-sync:checked) label[for="cat-sync"],
.page-faq .faq-shell:has(#cat-version:checked) label[for="cat-version"],
.page-faq .faq-shell:has(#cat-nav:checked) label[for="cat-nav"],
.page-faq .faq-shell:has(#cat-data:checked) label[for="cat-data"],
.page-faq .faq-shell:has(#cat-support:checked) label[for="cat-support"],
.page-faq #cat-all:checked ~ .faq-layout label[for="cat-all"] {
  background: var(--neon-green);
  border-color: var(--neon-green);
  color: var(--space-bg);
}
.page-faq .faq-shell:has(#cat-account:checked) label[for="cat-account"] .faq-cat-count,
.page-faq .faq-shell:has(#cat-sync:checked) label[for="cat-sync"] .faq-cat-count,
.page-faq .faq-shell:has(#cat-version:checked) label[for="cat-version"] .faq-cat-count,
.page-faq .faq-shell:has(#cat-nav:checked) label[for="cat-nav"] .faq-cat-count,
.page-faq .faq-shell:has(#cat-data:checked) label[for="cat-data"] .faq-cat-count,
.page-faq .faq-shell:has(#cat-support:checked) label[for="cat-support"] .faq-cat-count,
.page-faq #cat-all:checked ~ .faq-layout label[for="cat-all"] .faq-cat-count {
  color: rgba(10, 17, 40, 0.65);
}

/* 问题未解决？ */
.page-faq .faq-support {
  padding: 64px 0 0;
}
.page-faq .faq-support-card {
  display: grid;
  gap: 32px;
  padding: 32px 24px;
  background:
    radial-gradient(360px 200px at 100% 0%, rgba(0, 255, 163, 0.12), transparent 70%),
    var(--space-bg-2);
  border: 1px solid rgba(0, 255, 163, 0.22);
  border-radius: var(--faq-radius-lg);
}
.page-faq .faq-support-card .section-title {
  font-size: 26px;
}
.page-faq .faq-support-desc {
  margin-top: 12px;
  color: var(--muted-blue);
  line-height: 1.75;
}
.page-faq .faq-privacy-note {
  margin-top: 16px;
  color: var(--metal-silver);
  font-size: 14px;
}
.page-faq .faq-privacy-note a {
  color: var(--neon-green);
  text-decoration: underline;
  text-underline-offset: 4px;
}
.page-faq .faq-support-contact {
  display: grid;
  gap: 12px;
  align-content: start;
}
.page-faq .faq-contact-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 16px;
  background: rgba(10, 17, 40, 0.6);
  border: 1px solid rgba(174, 182, 194, 0.18);
  border-radius: 14px;
}
.page-faq .faq-contact-label {
  color: var(--metal-silver);
  font-size: 14px;
}
.page-faq .faq-contact-value {
  color: var(--near-white);
  font-family: var(--font-mono);
  font-size: 14px;
  text-align: right;
}
.page-faq .faq-support-contact .btn {
  justify-self: start;
  margin-top: 8px;
}

/* 返回顶部 */
.page-faq .faq-back-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 40;
  padding: 10px 14px;
  border-radius: 999px;
  background: var(--surface);
  border: 1px solid rgba(0, 255, 163, 0.5);
  color: var(--neon-green);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}
.page-faq .faq-back-top:hover {
  background: var(--neon-green);
  color: var(--space-bg);
  transform: translateY(-3px);
}

/* 响应式：平板与桌面布局 */
@media (min-width: 640px) {
  .page-faq .faq-hero {
    padding-top: calc(var(--header-h) + 64px);
  }
  .page-faq .faq-hero-grid {
    gap: 40px;
  }
  .page-faq .faq-item summary {
    padding: 20px 22px;
  }
  .page-faq .faq-answer {
    padding: 0 22px 22px 62px;
  }
}

@media (min-width: 900px) {
  .page-faq .faq-hero {
    padding-bottom: 68px;
  }
  .page-faq .faq-hero-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 48px;
  }
  .page-faq .faq-support-card {
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    padding: 40px 48px;
  }
}

@media (min-width: 960px) {
  .page-faq .faq-main {
    padding-top: 76px;
  }
  .page-faq .faq-layout {
    grid-template-columns: 280px minmax(0, 1fr);
    gap: 56px;
  }
  .page-faq .faq-index {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    padding: 28px 24px;
  }
  .page-faq .faq-cat-list {
    display: grid;
    gap: 10px;
  }
  .page-faq .faq-list-head {
    margin-bottom: 24px;
  }
}