/* ==========================================================================
   NBGeo 营销官网模板 — 全深色科技风
   品牌色仅通过 --brand / --brand-rgb 派生，后端替换 head 内联 style 即可换肤
   ========================================================================== */

:root {
  --brand: #4f6bff; /* 与 index.html head 内联注入默认值保持一致 */
  --brand-rgb: 79, 107, 255;

  --bg: #0b0e1a;
  --bg-alt: #111427;
  --bg-card: #141830;
  --text: #a5aec7;
  --text-strong: #ffffff;
  --text-dim: #6b7494;
  --line: #232a52;
  --line-soft: rgba(255, 255, 255, 0.07);

  --brand-light: color-mix(in srgb, var(--brand) 60%, #ffffff);
  --brand-deep: color-mix(in srgb, var(--brand) 70%, #000000);

  --radius-card: 16px;
  --radius-btn: 10px;
  --radius-shot: 12px;

  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* ---------- 基础 ---------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

/* 横向溢出兜底：真实溢出源已逐个消除，此处仅防御未来注入的超宽品牌资产 */
html, body { overflow-x: hidden; }
@supports (overflow-x: clip) {
  html, body { overflow-x: clip; }
}

img, svg { display: block; max-width: 100%; }
img { height: auto; }
img[src=""], img:not([src]) { display: none; }

h1, h2, h3, h4 { color: var(--text-strong); margin: 0 0 16px; line-height: 1.25; font-weight: 700; }
h2 { font-size: 36px; letter-spacing: -0.01em; }
h3 { font-size: 24px; }
p { margin: 0 0 16px; }
a { color: inherit; text-decoration: none; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow { max-width: 720px; }

.section { padding: 96px 0; position: relative; }
.section-alt { background: var(--bg-alt); }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  padding: 10px 16px;
  background: var(--brand);
  color: #fff;
  border-radius: 0 0 var(--radius-btn) 0;
  z-index: 200;
}
.skip-link:focus { left: 0; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: var(--radius-btn);
  font-weight: 600;
  font-size: 15px;
  line-height: 1;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.25s ease, background-color 0.2s ease, border-color 0.2s ease;
  white-space: nowrap;
}
.btn-sm { padding: 10px 18px; font-size: 14px; }
.btn-lg { padding: 16px 32px; font-size: 16px; }

.btn-primary {
  background: linear-gradient(135deg, var(--brand-light), var(--brand) 55%, var(--brand-deep));
  color: #fff;
  box-shadow: 0 0 0 1px rgba(var(--brand-rgb), 0.5), 0 6px 24px rgba(var(--brand-rgb), 0.45);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 0 1px rgba(var(--brand-rgb), 0.7), 0 10px 36px rgba(var(--brand-rgb), 0.6);
}

.btn-ghost {
  color: var(--text-strong);
  border-color: var(--line-soft);
  background: transparent;
}
.btn-ghost:hover { border-color: rgba(var(--brand-rgb), 0.6); color: var(--brand-light); }

.btn-outline {
  color: var(--text-strong);
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.03);
}
.btn-outline:hover { border-color: rgba(var(--brand-rgb), 0.6); transform: translateY(-2px); }

.btn-white {
  background: #fff;
  color: var(--brand-deep);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
}
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 12px 40px rgba(0, 0, 0, 0.45); }

/* ---------- 导航 ---------- */
.site-nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  transition: background-color 0.3s ease, border-color 0.3s ease, backdrop-filter 0.3s ease;
  border-bottom: 1px solid transparent;
}
.site-nav.is-scrolled {
  background: rgba(11, 14, 26, 0.78);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line-soft);
}
.nav-inner {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  min-height: 64px;
  padding-top: 8px;
  padding-bottom: 8px;
}
.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  color: var(--text-strong);
  margin-right: auto;
}
.nav-logo-img.is-broken { display: none; }
.nav-logo-mark { display: inline-flex; }
/* 代理配了 Logo 且加载成功时，内置的 N 占位标隐藏；Logo 为空或加载失败才显示占位标 */
.nav-logo-img:not([src=""]):not(.is-broken) + .nav-logo-mark { display: none; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-links > a {
  color: var(--text);
  font-size: 15px;
  transition: color 0.2s ease;
}
.nav-links > a:hover { color: var(--text-strong); }

.nav-actions { display: flex; align-items: center; gap: 12px; }
.nav-actions-inline { display: none; }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  background: transparent;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-btn);
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  height: 2px;
  background: var(--text-strong);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 180px 0 0;
  overflow: hidden;
  text-align: center;
}
.hero-bg { position: absolute; inset: 0; pointer-events: none; }
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 75%);
  mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 75%);
}
.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  will-change: transform;
}
.blob-1 {
  width: 560px; height: 560px;
  left: -120px; top: -160px;
  background: radial-gradient(circle, rgba(var(--brand-rgb), 0.5), transparent 65%);
  animation: drift-1 22s ease-in-out infinite alternate;
}
.blob-2 {
  width: 480px; height: 480px;
  right: -140px; top: 6%;
  background: radial-gradient(circle, rgba(var(--brand-rgb), 0.38), transparent 65%);
  animation: drift-2 26s ease-in-out infinite alternate;
}
.blob-3 {
  width: 420px; height: 420px;
  left: 34%; top: 34%;
  background: radial-gradient(circle, color-mix(in srgb, var(--brand) 40%, #8b5cf6), transparent 68%);
  opacity: 0.28;
  animation: drift-3 30s ease-in-out infinite alternate;
}
@keyframes drift-1 {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(90px, 60px) scale(1.12); }
}
@keyframes drift-2 {
  from { transform: translate(0, 0) scale(1.05); }
  to { transform: translate(-80px, 90px) scale(0.94); }
}
@keyframes drift-3 {
  from { transform: translate(0, 0); }
  to { transform: translate(-60px, -70px); }
}

.hero-inner { position: relative; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 20px;
  padding: 7px 16px;
  font-size: 14px;
  font-weight: 600;
  color: var(--brand-light);
  border: 1px solid rgba(var(--brand-rgb), 0.4);
  border-radius: 999px;
  background: rgba(var(--brand-rgb), 0.1);
}
.eyebrow::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--brand-light);
  box-shadow: 0 0 8px rgba(var(--brand-rgb), 0.9);
}

.hero-title {
  font-size: 56px;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}
.text-flow {
  background: linear-gradient(100deg, var(--brand-light), #ffffff 30%, var(--brand) 55%, var(--brand-light) 80%);
  background-size: 220% 100%;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  animation: text-flow 5s linear infinite;
}
@keyframes text-flow {
  from { background-position: 0% 0; }
  to { background-position: -220% 0; }
}

.hero-sub {
  max-width: 680px;
  margin: 0 auto 36px;
  font-size: 18px;
  color: var(--text);
}

.hero-cta {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 72px;
}

.hero-shot {
  perspective: 1400px;
  max-width: 960px;
  margin: 0 auto;
  padding-bottom: 96px;
}
.hero-shot-frame {
  border-radius: var(--radius-shot);
  box-shadow:
    0 0 0 1px rgba(var(--brand-rgb), 0.22),
    0 30px 90px rgba(0, 0, 0, 0.6),
    0 0 120px rgba(var(--brand-rgb), 0.18);
  transform: rotateX(8deg);
  animation: shot-float 7s ease-in-out infinite;
  transform-style: preserve-3d;
}
.hero-shot-frame svg { width: 100%; height: auto; border-radius: var(--radius-shot); }
@keyframes shot-float {
  0%, 100% { transform: rotateX(8deg) translateY(0); }
  50% { transform: rotateX(8deg) translateY(-12px); }
}

/* ---------- 跑马灯 ---------- */
.marquee-section {
  padding: 28px 0 36px;
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  background: var(--bg-alt);
}
.marquee-label {
  text-align: center;
  font-size: 14px;
  color: var(--text-dim);
  margin: 0 0 18px;
  letter-spacing: 0.08em;
}
.marquee {
  overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 12%, #000 88%, transparent);
}
.marquee-track {
  display: flex;
  width: max-content;
  animation: marquee 30s linear infinite;
}
.marquee-group {
  display: flex;
  align-items: center;
  gap: 64px;
  padding-right: 64px;
}
.marquee-item {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-dim);
  white-space: nowrap;
  letter-spacing: 0.04em;
}
@keyframes marquee {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

/* ---------- 通用板块头 ---------- */
.section-head {
  max-width: 720px;
  margin: 0 auto 64px;
  text-align: center;
}
.section-desc { font-size: 16px; margin: 0; }

/* ---------- 痛点卡片 ---------- */
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.pain-card {
  position: relative;
  padding: 32px 28px;
  border-radius: var(--radius-card);
  background: var(--bg-card);
  border: 1px solid var(--line);
  overflow: hidden;
  transition: border-color 0.3s ease, transform 0.3s ease;
}
.pain-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(320px circle at var(--mouse-x, 50%) var(--mouse-y, 50%),
    rgba(var(--brand-rgb), 0.16), transparent 70%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}
.pain-card:hover {
  border-color: rgba(var(--brand-rgb), 0.55);
  transform: translateY(-4px);
}
.pain-card:hover::before { opacity: 1; }
.pain-card h3 { font-size: 20px; margin-bottom: 12px; }
.pain-card p { margin: 0; font-size: 15px; }
.pain-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px; height: 52px;
  margin-bottom: 20px;
  border-radius: 14px;
  color: var(--brand-light);
  background: rgba(var(--brand-rgb), 0.12);
  border: 1px solid rgba(var(--brand-rgb), 0.3);
}

/* ---------- 工作原理 ---------- */
.steps {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}
.steps-line {
  position: absolute;
  top: 52px;
  left: 4%;
  width: 92%;
  height: 40px;
  z-index: 0;
  clip-path: inset(0 100% 0 0);
  transition: clip-path 1.4s ease 0.2s;
}
.steps.draw .steps-line { clip-path: inset(0 0 0 0); }
.step {
  position: relative;
  z-index: 1;
  padding: 8px 12px 0;
}
.step-num {
  font-size: 72px;
  font-weight: 800;
  line-height: 1;
  margin: 0 0 16px;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(var(--brand-rgb), 0.65);
  background: linear-gradient(180deg, rgba(var(--brand-rgb), 0.35), transparent);
  -webkit-background-clip: text;
  background-clip: text;
}
.step h3 { font-size: 22px; }
.step p { margin: 0; font-size: 15px; }

/* ---------- 核心功能 ---------- */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
  margin-bottom: 96px;
}
.feature-row:last-child { margin-bottom: 0; }
.feature-row:nth-child(even) .feature-text { order: 2; }
.feature-tag {
  display: inline-block;
  margin: 0 0 12px;
  padding: 4px 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--brand-light);
  background: rgba(var(--brand-rgb), 0.12);
  border: 1px solid rgba(var(--brand-rgb), 0.3);
  border-radius: 999px;
}
.feature-text p { font-size: 16px; }
.check-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.check-list li {
  position: relative;
  padding-left: 30px;
  font-size: 15px;
  color: var(--text-strong);
}
.check-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 4px;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: rgba(var(--brand-rgb), 0.16);
  border: 1px solid rgba(var(--brand-rgb), 0.5);
}
.check-list li::after {
  content: "";
  position: absolute;
  left: 5px; top: 9px;
  width: 8px; height: 5px;
  border-left: 2px solid var(--brand-light);
  border-bottom: 2px solid var(--brand-light);
  transform: rotate(-45deg);
}
.feature-media {
  border-radius: var(--radius-shot);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.5), 0 0 80px rgba(var(--brand-rgb), 0.1);
}
.feature-media svg { width: 100%; height: auto; border-radius: var(--radius-shot); }

/* ---------- 数据带 ---------- */
.stats-section {
  background: var(--bg-alt);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  overflow: hidden;
}
.stats-glow {
  position: absolute;
  left: 50%; top: 0;
  width: 900px; height: 420px;
  transform: translateX(-50%);
  background: radial-gradient(ellipse at 50% 0%, rgba(var(--brand-rgb), 0.22), transparent 70%);
  pointer-events: none;
}
.stats-grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  text-align: center;
}
.stat-num {
  font-size: 48px;
  font-weight: 800;
  line-height: 1.1;
  margin: 0 0 8px;
  color: var(--brand-light);
  text-shadow: 0 0 30px rgba(var(--brand-rgb), 0.5);
}
.stat-label { margin: 0; font-size: 14px; color: var(--text-dim); }

/* ---------- FAQ ---------- */
.faq-list { display: grid; gap: 14px; }
.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background: var(--bg-card);
  overflow: hidden;
  transition: border-color 0.25s ease;
}
.faq-item.is-open { border-color: rgba(var(--brand-rgb), 0.5); }
.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 20px 24px;
  background: none;
  border: 0;
  font-family: inherit;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-strong);
  text-align: left;
  cursor: pointer;
}
.faq-arrow {
  flex: none;
  color: var(--brand-light);
  transition: transform 0.3s ease;
}
.faq-item.is-open .faq-arrow { transform: rotate(180deg); }
.faq-a {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s ease;
}
.faq-item.is-open .faq-a { grid-template-rows: 1fr; }
.faq-a-inner { overflow: hidden; }
.faq-a-inner p {
  margin: 0;
  padding: 0 24px 22px;
  font-size: 15px;
}

/* 无 JS 时 FAQ 默认展开第一条以外也可读：通过 CSS 兜底全部展开 */
html:not(.has-js) .faq-a { grid-template-rows: 1fr; }

/* ---------- 收尾 CTA ---------- */
.cta-section { padding-top: 32px; }
.cta-card {
  position: relative;
  padding: 80px 40px;
  border-radius: 24px;
  text-align: center;
  background:
    radial-gradient(ellipse at 20% 0%, rgba(255, 255, 255, 0.22), transparent 50%),
    linear-gradient(135deg, var(--brand-light), var(--brand) 45%, var(--brand-deep));
  box-shadow: 0 30px 80px rgba(var(--brand-rgb), 0.4);
  overflow: hidden;
}
.cta-card h2 { color: #fff; margin-bottom: 12px; }
.cta-card p { color: rgba(255, 255, 255, 0.85); font-size: 17px; margin-bottom: 36px; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: #080a14;
  border-top: 1px solid var(--line-soft);
  padding: 72px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-brand-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 14px;
}
.footer-tagline { font-size: 14px; max-width: 280px; }
.footer-qr { margin-top: 20px; }
.footer-qr.is-hidden { display: none; }
.footer-qr:has(.footer-qr-img[src=""]) { display: none; }
.footer-qr-img {
  width: 88px; height: 88px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fff;
  padding: 4px;
}
.footer-qr-text { font-size: 13px; color: var(--text-dim); margin: 8px 0 0; }
.footer-col h4 {
  font-size: 14px;
  color: var(--text-strong);
  margin: 4px 0 16px;
  letter-spacing: 0.05em;
}
.footer-col a, .footer-col p {
  display: block;
  font-size: 14px;
  color: var(--text);
  margin: 0 0 10px;
  transition: color 0.2s ease;
}
.footer-col a:hover { color: var(--brand-light); }
.footer-bottom {
  border-top: 1px solid var(--line-soft);
  padding-top: 24px;
  text-align: center;
}
.footer-bottom p { font-size: 13px; color: var(--text-dim); margin: 0 0 6px; }
.footer-bottom p:last-child { margin-bottom: 0; }
.footer-bottom p:empty { display: none; }
.footer-bottom p.hide-when-empty.is-empty { display: none; }

/* ---------- 滚动显现 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.is-visible { opacity: 1; transform: none; }
html:not(.has-js) .reveal { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .nav-actions-desktop { display: none; }
  .nav-links {
    order: 3;
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    padding: 12px 0 8px;
  }
  .nav-links > a { padding: 10px 4px; font-size: 16px; }
  .nav-actions-inline { display: flex; margin-top: 12px; }

  /* 有 JS 时折叠为汉堡菜单；无 JS 时保持展开可读 */
  html.has-js .nav-toggle { display: flex; }
  html.has-js .nav-links { display: none; }
  html.has-js .nav-links.is-open {
    display: flex;
    background: rgba(11, 14, 26, 0.95);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
    border-radius: var(--radius-card);
    padding: 16px;
    border: 1px solid var(--line-soft);
  }

  .feature-row { grid-template-columns: 1fr; gap: 36px; margin-bottom: 72px; }
  .feature-row:nth-child(even) .feature-text { order: 0; }
  .pain-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 767px) {
  h2 { font-size: 28px; }
  .section { padding: 64px 0; }
  .hero { padding-top: 140px; }
  .hero-title { font-size: 36px; }
  .hero-sub { font-size: 16px; }
  .hero-cta { margin-bottom: 56px; }
  .hero-shot { padding-bottom: 64px; }
  .hero-shot-frame { transform: none; animation: none; }

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

  .steps { grid-template-columns: 1fr; gap: 32px; }
  .steps-line { display: none; }
  .step { padding: 0; }
  .step-num { font-size: 56px; }

  .stats-grid { grid-template-columns: 1fr 1fr; gap: 32px 16px; }
  .stat-num { font-size: 38px; }

  .cta-card { padding: 56px 24px; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .marquee-item { font-size: 17px; }
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .marquee-track { animation: none; width: 100%; }
  .marquee-group { flex-wrap: wrap; justify-content: center; padding-right: 0; }
  .marquee-group[aria-hidden="true"] { display: none; }
  .reveal { opacity: 1; transform: none; }
  .steps-line { clip-path: inset(0 0 0 0); }
  .hero-shot-frame { transform: none; }
  .text-flow { animation: none; background-position: 50% 0; }
}