/* 91PO官方网站 — 91-s.rest 独立视觉体系 */
:root {
  --bg-base: #0c0b10;
  --bg-surface: #14131a;
  --bg-card: #1c1b24;
  --bg-ribbon: #221f2b;
  --coral: #ff5722;
  --coral-soft: #ff8a65;
  --gold: #e8b84a;
  --gold-dim: rgba(232, 184, 74, 0.15);
  --azure: #4fc3f7;
  --azure-dim: rgba(79, 195, 247, 0.12);
  --text-hi: #f5f3ef;
  --text-mid: #a8a4b8;
  --text-lo: #6e6a7c;
  --line: rgba(255, 255, 255, 0.07);
  --line-gold: rgba(232, 184, 74, 0.35);
  --radius: 16px;
  --radius-pill: 999px;
  --nav-h: 60px;
  --ads-sticky-h: 0px;
  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font);
  background: var(--bg-base);
  color: var(--text-hi);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 20% -10%, rgba(255, 87, 34, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 90% 20%, rgba(79, 195, 247, 0.06), transparent),
    radial-gradient(ellipse 50% 30% at 50% 100%, rgba(232, 184, 74, 0.05), transparent);
  pointer-events: none;
  z-index: 0;
}

a { color: var(--coral-soft); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--coral); }

img { max-width: 100%; height: auto; display: block; }

.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
  position: relative;
  z-index: 1;
}

/* ── Header ── */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--nav-h);
  background: rgba(12, 11, 16, 0.94);
  border-bottom: 2px solid transparent;
  border-image: linear-gradient(90deg, transparent, var(--gold), var(--coral), transparent) 1;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-h);
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  color: var(--text-hi);
  font-weight: 700;
  font-size: 1.08rem;
  letter-spacing: 0.04em;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: 0 0 0 2px var(--gold-dim);
}

.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
}

.nav-links a {
  color: var(--text-mid);
  font-size: 0.86rem;
  padding: 7px 14px;
  border-radius: var(--radius-pill);
  transition: color 0.2s, background 0.2s;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-hi);
  background: var(--gold-dim);
}

.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--line);
  color: var(--text-hi);
  font-size: 1.3rem;
  padding: 4px 10px;
  border-radius: 8px;
  cursor: pointer;
}

/* ── Ads ── */
.ads-top-wrap {
  padding-top: calc(var(--nav-h) + 12px);
  position: relative;
  z-index: 2;
}

#ads, #ads-sticky {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 4px;
  background: transparent;
  margin: 8px 0;
}

#ads > div, #ads-sticky > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 25%;
  min-width: 70px;
  max-width: 90px;
  box-sizing: border-box;
}

#ads img, #ads-sticky img {
  width: 65px;
  height: 65px;
  object-fit: cover;
  border-radius: 18px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.35);
  transition: transform 0.18s, box-shadow 0.18s;
  border: 2px solid var(--line-gold);
}

#ads a, #ads-sticky a { border-radius: 18px; display: inline-block; }

#ads img:hover, #ads-sticky img:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 8px 22px rgba(255, 87, 34, 0.2);
}

#ads figcaption, #ads-sticky figcaption,
#ads .caption, #ads-sticky .caption {
  height: 15px;
  font-size: 11px;
  color: var(--text-lo);
  text-align: center;
  max-width: 90px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 4px;
}

.ads-sticky-bar {
  position: fixed;
  top: var(--nav-h);
  left: 0; right: 0;
  z-index: 999;
  background: rgba(20, 19, 26, 0.97);
  border-bottom: 1px solid var(--line-gold);
  padding: 6px 0;
  transform: translateY(-110%);
  opacity: 0;
  transition: transform 0.28s, opacity 0.28s;
  pointer-events: none;
}

.ads-sticky-bar.visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

body.ads-sticky-active { --ads-sticky-h: 88px; }

/* ── Hero ── */
.hero {
  padding: 48px 0 56px;
  text-align: center;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold);
  border: 1px solid var(--line-gold);
  padding: 5px 18px;
  border-radius: var(--radius-pill);
  margin-bottom: 22px;
}

.hero h1 {
  font-size: clamp(1.75rem, 5.5vw, 2.65rem);
  font-weight: 800;
  line-height: 1.35;
  margin-bottom: 18px;
  background: linear-gradient(135deg, var(--text-hi) 40%, var(--coral-soft) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-lead {
  font-size: 1.02rem;
  color: var(--text-mid);
  max-width: 640px;
  margin: 0 auto 32px;
}

.hero-pills {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.hero-pill {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 22px;
  min-width: 110px;
}

.hero-pill strong {
  display: block;
  font-size: 1.2rem;
  color: var(--coral-soft);
  line-height: 1.3;
}

.hero-pill span {
  font-size: 0.78rem;
  color: var(--text-lo);
}

/* ── Sections ── */
section { padding: 52px 0; }

.ribbon-head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 28px;
}

.ribbon-head::before {
  content: "";
  width: 4px;
  min-height: 48px;
  background: linear-gradient(180deg, var(--gold), var(--coral));
  border-radius: 4px;
  flex-shrink: 0;
  margin-top: 4px;
}

.ribbon-head h2 {
  font-size: clamp(1.35rem, 3.5vw, 1.75rem);
  font-weight: 700;
  line-height: 1.4;
}

.ribbon-head p {
  color: var(--text-mid);
  font-size: 0.95rem;
  margin-top: 6px;
}

/* 3:7 图文比例 */
.ratio-block {
  display: grid;
  grid-template-columns: 7fr 3fr;
  gap: 28px;
  align-items: start;
  margin-bottom: 40px;
}

.ratio-block.reverse { direction: rtl; }
.ratio-block.reverse > * { direction: ltr; }

.ratio-text h3 {
  font-size: 1.15rem;
  margin-bottom: 12px;
  color: var(--text-hi);
}

.ratio-text p {
  color: var(--text-mid);
  font-size: 0.94rem;
  margin-bottom: 10px;
}

.ratio-text ul {
  list-style: none;
  margin-top: 12px;
}

.ratio-text li {
  position: relative;
  padding-left: 18px;
  color: var(--text-mid);
  font-size: 0.9rem;
  margin-bottom: 6px;
}

.ratio-text li::before {
  content: "◆";
  position: absolute;
  left: 0;
  color: var(--gold);
  font-size: 0.55rem;
  top: 6px;
}

.ratio-img img {
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
}

.ratio-img figcaption {
  font-size: 0.75rem;
  color: var(--text-lo);
  text-align: center;
  margin-top: 8px;
}

/* Feature strip */
.feat-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin: 32px 0;
}

.feat-card {
  background: var(--bg-card);
  border-left: 3px solid var(--coral);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 20px 18px;
}

.feat-card:nth-child(2) { border-left-color: var(--azure); }
.feat-card:nth-child(3) { border-left-color: var(--gold); }
.feat-card:nth-child(4) { border-left-color: var(--coral-soft); }
.feat-card:nth-child(5) { border-left-color: var(--azure); }
.feat-card:nth-child(6) { border-left-color: var(--gold); }

.feat-card h4 {
  font-size: 0.95rem;
  margin-bottom: 8px;
}

.feat-card p {
  font-size: 0.84rem;
  color: var(--text-mid);
  line-height: 1.65;
}

/* Highlight band */
.band {
  background: var(--bg-ribbon);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 48px 0;
}

.band-inner {
  display: grid;
  grid-template-columns: 7fr 3fr;
  gap: 32px;
  align-items: center;
}

.band-text p {
  color: var(--text-mid);
  font-size: 0.94rem;
  margin-bottom: 10px;
}

/* CTA */
.cta-panel {
  text-align: center;
  background: linear-gradient(135deg, var(--bg-card), var(--bg-ribbon));
  border: 1px solid var(--line-gold);
  border-radius: var(--radius);
  padding: 40px 24px;
  margin: 20px 0;
}

.cta-panel h2 {
  font-size: 1.4rem;
  margin-bottom: 12px;
}

.cta-panel p {
  color: var(--text-mid);
  margin-bottom: 22px;
  font-size: 0.94rem;
}

.btn-glow {
  display: inline-block;
  background: linear-gradient(135deg, var(--coral), #e64a19);
  color: #fff;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 36px;
  border-radius: var(--radius-pill);
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 20px rgba(255, 87, 34, 0.35);
}

.btn-glow:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(255, 87, 34, 0.45);
}

/* FAQ timeline */
.faq-list { margin-top: 24px; }

.faq-item {
  border-left: 2px solid var(--line);
  padding: 0 0 20px 22px;
  margin-left: 8px;
  position: relative;
}

.faq-item::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--bg-base);
  border: 2px solid var(--gold);
}

.faq-q {
  background: none;
  border: none;
  color: var(--text-hi);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  width: 100%;
  padding: 4px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-q::after {
  content: "+";
  color: var(--coral);
  font-size: 1.2rem;
  transition: transform 0.2s;
}

.faq-item.open .faq-q::after { transform: rotate(45deg); }

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s;
  color: var(--text-mid);
  font-size: 0.9rem;
}

.faq-item.open .faq-a { max-height: 300px; padding-top: 8px; }

/* Prose (subpages) */
.page-hero {
  padding: calc(var(--nav-h) + 36px) 0 28px;
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  font-size: clamp(1.4rem, 4vw, 1.9rem);
  margin-bottom: 8px;
}

.page-hero p { color: var(--text-mid); font-size: 0.92rem; }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 0.82rem;
  color: var(--text-lo);
  margin-bottom: 16px;
}

.breadcrumb a { color: var(--text-mid); }
.breadcrumb span.sep { color: var(--text-lo); }

.prose {
  padding: 36px 0 60px;
  max-width: 800px;
}

.prose h2 {
  font-size: 1.15rem;
  margin: 28px 0 12px;
  color: var(--coral-soft);
}

.prose h3 {
  font-size: 1rem;
  margin: 20px 0 8px;
}

.prose p, .prose li {
  color: var(--text-mid);
  font-size: 0.92rem;
  margin-bottom: 10px;
}

.prose ul, .prose ol {
  padding-left: 22px;
  margin-bottom: 14px;
}

.prose li { margin-bottom: 6px; }

/* Footer */
.site-footer {
  background: var(--bg-surface);
  border-top: 1px solid var(--line);
  padding: 44px 0 28px;
  margin-top: 20px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.footer-brand p {
  color: var(--text-lo);
  font-size: 0.85rem;
  margin-top: 10px;
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 0.88rem;
  color: var(--gold);
  margin-bottom: 12px;
  letter-spacing: 0.06em;
}

.footer-col a {
  display: block;
  color: var(--text-mid);
  font-size: 0.84rem;
  margin-bottom: 8px;
}

.footer-col a:hover { color: var(--coral-soft); }

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 18px;
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-lo);
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 10px;
}

/* Prose-only SEO block */
.prose-block {
  margin: 36px 0;
  padding: 28px 24px;
  background: var(--bg-card);
  border-radius: var(--radius);
  border: 1px solid var(--line);
}

.prose-block h3 {
  font-size: 1.1rem;
  margin-bottom: 12px;
  color: var(--coral-soft);
}

.prose-block p {
  color: var(--text-mid);
  font-size: 0.93rem;
  margin-bottom: 12px;
  line-height: 1.85;
}

.prose-block h3 + h3,
.prose-block p + h3 {
  margin-top: 22px;
}

/* Module grid */
.module-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.module-item {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-top: 2px solid var(--gold);
  border-radius: var(--radius);
  padding: 20px 18px;
}

.module-item:nth-child(2) { border-top-color: var(--coral); }
.module-item:nth-child(3) { border-top-color: var(--azure); }
.module-item:nth-child(4) { border-top-color: var(--coral-soft); }
.module-item:nth-child(5) { border-top-color: var(--gold); }
.module-item:nth-child(6) { border-top-color: var(--azure); }

.module-item h4 {
  font-size: 0.95rem;
  margin-bottom: 8px;
}

.module-item p {
  font-size: 0.84rem;
  color: var(--text-mid);
  line-height: 1.7;
}

.footer-kw {
  display: block;
  color: var(--text-lo);
  font-size: 0.84rem;
  margin-bottom: 8px;
}

.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-h) + 40px) 20px 60px;
}

.error-code {
  font-size: 5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--gold), var(--coral));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
}

.error-page h1 { font-size: 1.3rem; margin: 12px 0; }
.error-page p { color: var(--text-mid); margin-bottom: 24px; }

/* Responsive */
@media (max-width: 768px) {
  .menu-toggle { display: block; }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0; right: 0;
    background: rgba(12, 11, 16, 0.98);
    flex-direction: column;
    padding: 12px 20px 20px;
    border-bottom: 1px solid var(--line);
  }

  .nav-links.open { display: flex; }

  .ratio-block,
  .band-inner {
    grid-template-columns: 1fr;
  }

  .ratio-block.reverse { direction: ltr; }

  .ratio-img { max-width: 220px; margin: 0 auto; }

  .feat-strip { grid-template-columns: 1fr; }

  .module-grid { grid-template-columns: 1fr; }

  .footer-grid { grid-template-columns: 1fr; }

  #ads > div, #ads-sticky > div { width: 25%; }
}

@media (min-width: 769px) {
  body.ads-sticky-active main,
  body.ads-sticky-active .page-hero { padding-top: 0; }
}