.page-faq {
  --faq-rail: 236px;
  --faq-sticky: calc(var(--nav-h) + 18px);
  color: var(--text);
  background:
    radial-gradient(120% 70% at 88% -12%, rgba(45, 127, 191, 0.18), transparent 62%),
    radial-gradient(90% 60% at 0% 8%, rgba(240, 90, 40, 0.10), transparent 58%),
    var(--ink-900);
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    114deg,
    rgba(38, 68, 95, 0.55) 0 1px,
    transparent 1px 44px
  );
  opacity: 0.55;
  pointer-events: none;
}

.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  left: -80px;
  bottom: -140px;
  width: 320px;
  height: 320px;
  border: 1px solid rgba(240, 90, 40, 0.28);
  border-radius: 50%;
  pointer-events: none;
}

.page-faq .faq-hero__inner {
  position: relative;
  display: grid;
  gap: 26px;
  padding-top: clamp(22px, 5vw, 52px);
  padding-bottom: clamp(30px, 6vw, 58px);
}

.page-faq .faq-hero__lead {
  display: flex;
  flex-direction: column;
  gap: 16px;
  min-width: 0;
}

.page-faq .faq-hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 7vw, 60px);
  line-height: 1.08;
  letter-spacing: -0.01em;
  max-width: 16em;
}

.page-faq .faq-hero__intro {
  margin: 0;
  max-width: 46em;
  color: var(--text-2);
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.78;
}

.page-faq .faq-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 4px 0 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-hero__figure {
  margin: 0;
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
  background: var(--ink-800);
  overflow: hidden;
}

.page-faq .faq-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 主布局 ---------- */
.page-faq .faq-layout {
  display: grid;
  gap: 26px;
  padding-top: clamp(26px, 5vw, 54px);
  padding-bottom: clamp(48px, 8vw, 92px);
}

.page-faq .faq-rail {
  display: flex;
  flex-direction: column;
  gap: 14px;
  min-width: 0;
}

.page-faq .faq-rail__title {
  margin: 0;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--text-3);
}

.page-faq .faq-rail__nav {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding-bottom: 6px;
  scrollbar-width: thin;
}

.page-faq .faq-rail__link {
  flex: none;
  display: block;
  padding: 8px 12px;
  border-left: 2px solid var(--line);
  color: var(--text-2);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-decoration: none;
  white-space: nowrap;
  background: rgba(14, 36, 57, 0.55);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-faq .faq-rail__link:hover,
.page-faq .faq-rail__link:focus-visible {
  color: var(--text);
  border-left-color: var(--accent);
  background: rgba(240, 90, 40, 0.10);
}

.page-faq .faq-rail__card {
  display: none;
  padding: 16px 16px 18px;
  border: 1px solid var(--line);
  border-top: 2px solid var(--accent);
  background: var(--ink-800);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-faq .faq-rail__card-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
}

.page-faq .faq-rail__card-text {
  margin: 0 0 14px;
  color: var(--text-2);
  font-size: 13px;
  line-height: 1.7;
  word-break: break-word;
}

.page-faq .faq-main {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 22px;
}

/* ---------- 筛选条 ---------- */
.page-faq .faq-filter {
  position: sticky;
  top: calc(var(--nav-h) + 6px);
  z-index: 6;
  padding: 10px;
  border: 1px solid var(--line);
  background: rgba(8, 24, 39, 0.94);
  backdrop-filter: blur(8px);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
}

/* ---------- 顶部配图 ---------- */
.page-faq .faq-figure {
  margin: 0;
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
  overflow: hidden;
  background: var(--ink-800);
}

.page-faq .faq-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 问题分组 ---------- */
.page-faq .qa-group {
  display: grid;
  gap: 12px;
  margin-bottom: 30px;
  scroll-margin-top: calc(var(--nav-h) + 96px);
}

.page-faq .qa-group:last-child {
  margin-bottom: 0;
}

.page-faq .qa-group__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 9px;
  border-bottom: 1px solid var(--line);
}

.page-faq .qa-group__index {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--accent);
}

.page-faq .qa-group__head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 3.2vw, 27px);
  line-height: 1.3;
}

.page-faq .qa-group__list {
  display: grid;
  gap: 10px;
}

/* ---------- 单条问答 ---------- */
.page-faq .qa {
  border: 1px solid var(--line);
  background: var(--ink-800);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-faq .qa:hover {
  border-color: var(--ink-700);
  background: #102941;
}

.page-faq .qa[open] {
  border-color: rgba(240, 90, 40, 0.65);
  background: #102941;
}

.page-faq .qa[data-filtered="out"] {
  display: none;
}

.page-faq .qa__q {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-body);
  font-size: clamp(15px, 2.1vw, 17px);
  font-weight: 600;
  line-height: 1.55;
  color: var(--text);
}

.page-faq .qa__q::-webkit-details-marker {
  display: none;
}

.page-faq .qa__q:focus-visible {
  outline: 2px solid var(--accent-soft);
  outline-offset: -3px;
}

.page-faq .qa__q-text {
  min-width: 0;
}

.page-faq .qa__sign {
  position: relative;
  flex: none;
  width: 22px;
  height: 22px;
  margin-top: 2px;
  border: 1px solid var(--line);
  transition: border-color var(--dur) var(--ease);
}

.page-faq .qa__sign::before,
.page-faq .qa__sign::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 2px;
  background: var(--accent-soft);
  transform: translate(-50%, -50%);
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.page-faq .qa__sign::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.page-faq .qa[open] .qa__sign {
  border-color: var(--accent);
}

.page-faq .qa[open] .qa__sign::after {
  transform: translate(-50%, -50%) rotate(0deg);
  opacity: 0;
}

.page-faq .qa__a {
  padding: 0 16px 16px;
  border-top: 1px solid rgba(38, 68, 95, 0.7);
  padding-top: 12px;
}

.page-faq .qa__a p {
  margin: 0 0 10px;
  color: var(--text-2);
  font-size: 14.5px;
  line-height: 1.78;
}

.page-faq .qa__a p:last-child {
  margin-bottom: 0;
}

.page-faq .qa__a a {
  color: var(--accent-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-faq .qa__a a:hover,
.page-faq .qa__a a:focus-visible {
  color: var(--text);
}

/* 筛选后整组无匹配时收起该组 */
.page-faq .qa-group:not(:has(.qa:not([data-filtered="out"]))) {
  display: none;
}

/* ---------- 中等屏 ---------- */
@media (min-width: 620px) {
  .page-faq .faq-hero__meta {
    gap: 10px;
  }

  .page-faq .qa__q {
    padding: 17px 20px;
  }

  .page-faq .qa__a {
    padding: 14px 20px 18px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-faq .faq-hero__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: center;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-faq .faq-hero__figure {
    align-self: stretch;
  }

  .page-faq .faq-hero__figure img {
    height: 100%;
    min-height: 300px;
  }

  .page-faq .faq-layout {
    grid-template-columns: var(--faq-rail) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-faq .faq-rail {
    position: sticky;
    top: var(--faq-sticky);
    align-self: start;
  }

  .page-faq .faq-rail__nav {
    flex-direction: column;
    gap: 4px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-faq .faq-rail__link {
    white-space: normal;
    background: transparent;
  }

  .page-faq .faq-rail__card {
    display: block;
    margin-top: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .qa,
  .page-faq .qa__sign,
  .page-faq .qa__sign::before,
  .page-faq .qa__sign::after,
  .page-faq .faq-rail__link {
    transition: none;
  }
}