/* ============================================================
   机隐科技官网 — 设计稿像素还原
   设计令牌：科技蓝深色 #0A1424 · 卡片 #122340 · 强调渐变 #3D7BF6→#38BDF8
   字体：Noto Sans SC
   ============================================================ */

:root {
  /* 颜色令牌 */
  --bg-main: #0A1424;
  --bg-alt: #0C1A30;
  --bg-footer: #071020;
  --card: #122340;
  --text-main: #EAF1FF;
  --text-sub: #9DB2D4;
  --text-weak: #6B82A6;
  --label: #7FB0FF;
  --blue: #3D7BF6;
  --cyan: #38BDF8;
  --grad: linear-gradient(90deg, #3D7BF6 0%, #38BDF8 100%);

  /* 圆角 */
  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 16px;

  /* 布局 */
  --container: 1280px;
  --header-h: 72px;
  --section-pad: 96px;

  /* 字体 */
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;

  /* 阴影 */
  --shadow-card: 0 8px 32px rgba(3, 10, 24, 0.45);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; }

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow { max-width: 900px; }

/* ---------- Header ---------- */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(11, 22, 38, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.header-inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.logo { display: flex; align-items: center; gap: 10px; }
.logo-mark { flex-shrink: 0; }
.logo-text { font-size: 20px; font-weight: 700; color: var(--text-main); white-space: nowrap; }

.nav { display: flex; align-items: center; gap: 32px; }
.nav-link {
  font-size: 15px;
  color: var(--text-sub);
  transition: color 0.25s;
  white-space: nowrap;
}
.nav-link:hover { color: var(--text-main); }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: none;
  border-radius: var(--r-sm);
  font-size: 15px;
  font-weight: 700;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
  white-space: nowrap;
}
.btn-primary { background: var(--grad); color: #fff; }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 8px 24px rgba(61, 123, 246, 0.35); }
.btn-outline {
  background: transparent;
  color: var(--label);
  border: 1px solid rgba(127, 176, 255, 0.6);
}
.btn-outline:hover { border-color: var(--label); background: rgba(61, 123, 246, 0.10); }
.btn-lg { padding: 15px 30px; border-radius: 10px; font-size: 15px; }
.btn-xl { padding: 16px 36px; border-radius: 10px; font-size: 16px; }
.btn-block { width: 100%; padding: 12px 24px; font-size: 14px; }
.btn-header { padding: 11px 22px; font-size: 14px; }

/* 汉堡菜单（移动端） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px; height: 40px;
  background: transparent;
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 8px;
  padding: 9px;
}
.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--text-sub);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Section 通用 ---------- */
.section {
  padding: var(--section-pad) 0;
  display: flex;
  justify-content: center;
  text-align: center;
}
.section > .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}

.section-label {
  font-size: 14px;
  font-weight: 500;
  color: var(--label);
  letter-spacing: 1px;
}
.section-title {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-main);
  max-width: 900px;
}
.section-sub {
  font-size: 17px;
  font-weight: 300;
  color: var(--text-sub);
  max-width: 760px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: calc(var(--header-h) + 88px) 0 76px;
  text-align: center;
  overflow: hidden;
  background: var(--bg-main);
}

.hero-glow { position: absolute; border-radius: 50%; pointer-events: none; }
.hero-glow-blue {
  top: -180px; left: 50%; transform: translateX(-50%);
  width: 900px; height: 640px;
  background: radial-gradient(closest-side, rgba(61,123,246,0.30), rgba(61,123,246,0));
}
.hero-glow-cyan {
  top: 40px; right: -160px;
  width: 760px; height: 600px;
  background: radial-gradient(closest-side, rgba(56,189,248,0.20), rgba(56,189,248,0));
}

.hero-inner { position: relative; display: flex; flex-direction: column; align-items: center; gap: 26px; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 999px;
  background: rgba(61,123,246,0.12);
  border: 1px solid rgba(61,123,246,0.40);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-sub);
}
.hero-badge-dot { width: 7px; height: 7px; border-radius: 999px; background: var(--cyan); }

.hero-title {
  font-size: 56px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-main);
  max-width: 900px;
}
.hero-sub {
  font-size: 18px;
  font-weight: 300;
  color: var(--text-sub);
  max-width: 760px;
}
.hero-ctas { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.hero-trust { font-size: 14px; color: var(--text-weak); }

.hero-visual {
  width: 100%;
  max-width: 1040px;
  margin-top: 12px;
  border-radius: var(--r-lg);
  border: 1px solid rgba(61,123,246,0.25);
  overflow: hidden;
  background: linear-gradient(180deg, #12233F 0%, #1A3358 100%);
  box-shadow: 0 24px 60px rgba(3, 10, 24, 0.55);
}
.hero-visual img { width: 100%; height: auto; object-fit: cover; }

/* ---------- 区块背景交替 ---------- */
.capabilities { background: var(--bg-main); }
.services { background: var(--bg-alt); }
.social-proof { background: var(--bg-main); }
.pricing { background: var(--bg-alt); }
.faq { background: var(--bg-main); }
.final-cta { background: var(--bg-alt); }

/* ---------- 卡片网格 ---------- */
.card-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
  width: 100%;
  max-width: 1280px;
}
.card-grid-2 { max-width: 1280px; }
.card-grid-4 { max-width: 1280px; }

.card {
  background: var(--card);
  border: 1px solid rgba(61,123,246,0.12);
  border-radius: var(--r-lg);
  padding: 32px;
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: transform 0.25s, border-color 0.25s;
}
.card:hover { transform: translateY(-4px); border-color: rgba(61,123,246,0.35); }

.card-grid-2 .card { width: calc(50% - 12px); min-height: 260px; }
.card-grid-4 .card { width: calc(25% - 18px); min-height: 230px; }

.card-icon {
  width: 40px; height: 40px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 10px;
  background: rgba(61,123,246,0.12);
  border: 1px solid rgba(61,123,246,0.18);
}
.card-title { font-size: 20px; font-weight: 700; color: var(--text-main); }
.card-grid-4 .card-title { font-size: 18px; }
.card-desc { font-size: 15px; color: var(--text-sub); line-height: 1.7; }
.card-grid-4 .card-desc { font-size: 14px; }

/* ---------- 案例区 ---------- */
.stats {
  display: flex;
  gap: 80px;
  align-items: center;
  justify-content: center;
  margin-top: 24px;
}
.stat { display: flex; flex-direction: column; gap: 8px; align-items: center; }
.stat-value { font-size: 48px; font-weight: 700; color: var(--text-main); }
.stat-label { font-size: 14px; color: var(--text-sub); }

.cases-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 16px;
}
.case-card {
  background: var(--card);
  border: 1px solid rgba(61,123,246,0.10);
  border-radius: var(--r-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  text-align: left;
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}
.case-card:hover {
  transform: translateY(-6px);
  border-color: rgba(61,123,246,0.40);
  box-shadow: 0 16px 40px rgba(3, 10, 24, 0.5);
}
.case-cover {
  height: 148px;
  background: linear-gradient(135deg, #234E9C 0%, #2E8FD6 100%);
  position: relative;
  overflow: hidden;
}
.case-cover::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(10,20,36,0) 0%, rgba(10,20,36,0.45) 100%);
  pointer-events: none;
}
.case-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  display: block;
  transition: transform 0.45s ease;
}
.case-card:hover .case-cover img { transform: scale(1.06); }
.case-body {
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  flex: 1;
}
.case-tag {
  align-self: flex-start;
  font-size: 12px;
  font-weight: 600;
  color: var(--cyan);
  background: rgba(56,189,248,0.12);
  border: 1px solid rgba(56,189,248,0.30);
  padding: 4px 12px;
  border-radius: 999px;
}
.case-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.4;
  margin: 0;
}
.case-desc {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.7;
  margin: 0;
}
.case-result {
  margin-top: auto;
  margin-bottom: 0;
  padding-top: 4px;
  font-size: 13px;
  font-weight: 500;
  color: #7CE7C2;
}

.credentials {
  font-size: 15px;
  color: var(--text-weak);
  margin-top: 40px;
}

/* ---------- 报价区 ---------- */
.pricing-grid {
  display: flex;
  gap: 24px;
  justify-content: center;
  align-items: stretch;
  flex-wrap: wrap;
  max-width: 1160px;
}
.price-card {
  width: 360px;
  background: var(--card);
  border: 1px solid rgba(61,123,246,0.12);
  border-radius: var(--r-lg);
  padding: 32px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  text-align: left;
  transition: transform 0.25s, border-color 0.25s;
}
.price-card:hover { transform: translateY(-4px); border-color: rgba(61,123,246,0.35); }
.price-title { font-size: 20px; font-weight: 700; color: var(--text-main); }
.price-value { font-size: 30px; font-weight: 700; color: var(--text-main); line-height: 1.2; }
.price-feats {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 14px;
  color: var(--text-sub);
  flex: 1;
}
.price-feats li { position: relative; padding-left: 16px; }
.price-feats li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--label);
  font-weight: 700;
}

/* ---------- FAQ ---------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  width: 100%;
  max-width: 900px;
  margin-top: 8px;
  text-align: left;
}
.faq-item {
  background: var(--card);
  border: 1px solid rgba(61,123,246,0.10);
  border-radius: var(--r-md);
  overflow: hidden;
}
.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 24px;
  background: transparent;
  border: none;
  font-size: 17px;
  font-weight: 700;
  color: var(--text-main);
  text-align: left;
}
.faq-icon {
  position: relative;
  width: 18px; height: 18px;
  flex-shrink: 0;
  border-radius: 50%;
  border: 1.5px solid var(--label);
  transition: transform 0.3s;
}
.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  background: var(--label);
  border-radius: 1px;
}
.faq-icon::before { width: 8px; height: 1.5px; }
.faq-icon::after { width: 1.5px; height: 8px; }
.faq-item.open .faq-icon { transform: rotate(45deg); }

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}
.faq-answer p {
  padding: 0 24px 24px;
  font-size: 15px;
  color: var(--text-sub);
  line-height: 1.8;
}
.faq-item.open .faq-answer { max-height: 240px; }

/* ---------- 收尾 CTA ---------- */
.final-cta .section-title { margin-top: 12px; }
.final-trust { font-size: 14px; color: var(--text-weak); margin-top: 8px; }

/* ---------- Footer ---------- */
.footer {
  position: relative;
  background: var(--bg-footer);
  padding: 48px 0;
}
.footer-accent {
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, rgba(61,123,246,0) 0%, var(--blue) 50%, rgba(56,189,248,0) 100%);
}
.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  text-align: center;
}
.footer-logo .logo-text { font-size: 18px; }
.footer-tagline { font-size: 15px; color: var(--text-sub); }
.footer-nav { display: flex; gap: 32px; flex-wrap: wrap; justify-content: center; }
.footer-nav a { font-size: 14px; color: var(--text-sub); transition: color 0.25s; }
.footer-nav a:hover { color: var(--text-main); }

.wechat-service {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 8px;
}
.wechat-qr {
  width: 72px; height: 72px;
  border-radius: 8px;
  border: 1px solid rgba(61,123,246,0.30);
  object-fit: cover;
  flex-shrink: 0;
}
.wechat-service-text { display: flex; flex-direction: column; gap: 8px; }
.wechat-service-tip { font-size: 14px; color: var(--text-main); font-weight: 500; margin: 0; }
.wechat-service-sub { font-size: 13px; color: var(--text-sub); margin: 0; }
.wechat-chat-btn {
  align-self: flex-start;
  font-size: 14px;
  padding: 9px 20px;
  border-radius: 999px;
  cursor: pointer;
}

.footer-copy { font-size: 13px; color: var(--text-weak); margin-top: 8px; }

/* ---------- 内容默认可见；动画由 JS 单独启用（当前版本关闭，保持稳定可见） ---------- */
.reveal { opacity: 1; transform: none; }
@media (prefers-reduced-motion: no-preference) {
  .anim-on-scroll .reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
  .anim-on-scroll .reveal.visible { opacity: 1; transform: none; }
}

/* ============================================================
   响应式
   ============================================================ */

@media (max-width: 1024px) {
  .card-grid-4 .card { width: calc(50% - 12px); }
  .cases-grid { grid-template-columns: repeat(2, 1fr); }
  .stats { gap: 48px; }
  .stat-value { font-size: 40px; }
}

@media (max-width: 768px) {
  :root { --section-pad: 64px; }

  .nav {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--bg-alt);
    border-bottom: 1px solid rgba(255,255,255,0.08);
    padding: 8px 24px 16px;
    transform: translateY(-120%);
    transition: transform 0.35s ease;
    z-index: 99;
  }
  .nav.open { transform: translateY(0); }
  .nav-link { display: block; width: 100%; padding: 14px 0; font-size: 16px; border-bottom: 1px solid rgba(255,255,255,0.05); }
  .nav-link:last-child { border-bottom: none; }

  .nav-toggle { display: flex; }
  .btn-header { display: none; }

  .hero { padding-top: calc(var(--header-h) + 56px); }
  .hero-title { font-size: 38px; }
  .hero-sub { font-size: 16px; }
  .hero-ctas { flex-direction: column; width: 100%; max-width: 320px; }
  .hero-ctas .btn { width: 100%; }

  .section-title { font-size: 30px; }
  .section-sub { font-size: 15px; }

  .card-grid-2 .card,
  .card-grid-4 .card { width: 100%; }

  .stats { flex-direction: column; gap: 32px; }
  .stat-value { font-size: 36px; }

  .cases-grid { grid-template-columns: 1fr; gap: 16px; }

  .pricing-grid { flex-direction: column; align-items: center; }
  .price-card { width: 100%; max-width: 400px; }

  .footer-nav { gap: 20px; }
  .wechat-service { flex-direction: column; gap: 12px; text-align: center; }
  .wechat-service p { text-align: center; }
  .wechat-chat-btn { align-self: center; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 30px; }
  .hero-badge { font-size: 12px; padding: 6px 12px; }
  .container { padding: 0 18px; }
}