/* =========================================================
   北京识元科技有限公司 · 官网样式
   设计语言：科技感 / 渐变蓝紫 / 玻璃拟态 / 深色首屏
   ========================================================= */

:root {
  --primary: #4f8cff;
  --primary-dark: #3a6ef0;
  --accent: #7c5cff;
  --accent-2: #00d4ff;
  --ink: #101828;
  --ink-2: #475467;
  --ink-3: #98a2b3;
  --bg: #ffffff;
  --bg-alt: #f6f8ff;
  --line: #e6eaf5;
  --grad: linear-gradient(120deg, #4f8cff 0%, #7c5cff 55%, #b45cff 100%);
  --grad-2: linear-gradient(120deg, #00d4ff 0%, #4f8cff 100%);
  --shadow-sm: 0 1px 3px rgba(16, 24, 40, 0.06), 0 1px 2px rgba(16, 24, 40, 0.04);
  --shadow-md: 0 10px 30px rgba(76, 110, 245, 0.12);
  --shadow-lg: 0 24px 60px rgba(76, 110, 245, 0.18);
  --radius: 16px;
  --nav-h: 72px;
  --font: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -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: min(1180px, 92%);
  margin: 0 auto;
}

.grad-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ===================== 按钮 ===================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: none;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
  white-space: nowrap;
}
.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 8px 24px rgba(99, 102, 241, 0.35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 32px rgba(99, 102, 241, 0.45);
}
.btn-ghost {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(4px);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); transform: translateY(-2px); }
.btn-lg { padding: 15px 38px; font-size: 16px; }
.btn-block { width: 100%; }

/* ===================== 导航栏 ===================== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 1000;
  display: flex;
  align-items: center;
  background: transparent;
  transition: background 0.35s ease, box-shadow 0.35s ease, backdrop-filter 0.35s ease;
}
.navbar.scrolled {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 var(--line), var(--shadow-sm);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; width: min(1180px, 92%); margin: 0 auto; }

.brand { display: flex; align-items: center; gap: 12px; }
.brand-logo {
  width: 44px; height: 44px;
  display: grid; place-items: center;
  border-radius: 12px;
  background: var(--grad);
  color: #fff;
  font-size: 22px;
  font-weight: 800;
  box-shadow: 0 6px 18px rgba(99, 102, 241, 0.4);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-text strong { font-size: 19px; letter-spacing: 1px; color: var(--ink); }
.navbar:not(.scrolled) .brand-text strong { color: #fff; }
.brand-text small { font-size: 10px; letter-spacing: 3px; color: var(--ink-3); }
.navbar:not(.scrolled) .brand-text small { color: rgba(255, 255, 255, 0.6); }

.nav-links { display: flex; align-items: center; gap: 34px; }
.nav-links a {
  font-size: 15px;
  color: var(--ink-2);
  position: relative;
  padding: 6px 0;
  transition: color 0.25s ease;
}
.navbar:not(.scrolled) .nav-links a { color: rgba(255, 255, 255, 0.85); }
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; bottom: 0;
  width: 0; height: 2px;
  border-radius: 2px;
  background: var(--grad);
  transition: width 0.3s ease;
}
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.navbar:not(.scrolled) .nav-links a:hover,
.navbar:not(.scrolled) .nav-links a.active { color: #fff; }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

.nav-cta { padding: 9px 22px; font-size: 14px; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  padding: 8px;
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}
.navbar:not(.scrolled) .nav-toggle span { background: #fff; }
.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); }

/* ===================== 首屏 Hero ===================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: radial-gradient(1200px 800px at 70% -10%, #1b2b5e 0%, #0c1330 45%, #070b1e 100%);
  color: #fff;
  overflow: hidden;
  padding: calc(var(--nav-h) + 40px) 0 80px;
}
.hero-canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
.hero-glow { position: absolute; border-radius: 50%; filter: blur(90px); opacity: 0.5; pointer-events: none; }
.hero-glow-1 { width: 480px; height: 480px; background: rgba(79, 140, 255, 0.5); top: -120px; right: -80px; animation: float 9s ease-in-out infinite; }
.hero-glow-2 { width: 420px; height: 420px; background: rgba(124, 92, 255, 0.45); bottom: -140px; left: -100px; animation: float 11s ease-in-out infinite reverse; }

@keyframes float {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(26px) scale(1.06); }
}

.hero-inner { position: relative; z-index: 2; text-align: center; }
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 9px 20px;
  border-radius: 999px;
  font-size: 14px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(8px);
  margin-bottom: 26px;
}
.pulse-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: #4ade80;
  box-shadow: 0 0 0 0 rgba(74, 222, 128, 0.6);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(74, 222, 128, 0.6); }
  70% { box-shadow: 0 0 0 10px rgba(74, 222, 128, 0); }
  100% { box-shadow: 0 0 0 0 rgba(74, 222, 128, 0); }
}

.hero-title {
  font-size: clamp(40px, 6.4vw, 72px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: 1px;
  margin-bottom: 22px;
}
.hero-sub {
  max-width: 660px;
  margin: 0 auto 38px;
  font-size: clamp(15px, 1.6vw, 18px);
  color: rgba(255, 255, 255, 0.75);
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 64px; }

.hero-stats {
  display: flex;
  justify-content: center;
  gap: clamp(28px, 6vw, 80px);
  flex-wrap: wrap;
}
.stat { text-align: center; }
.stat-num {
  font-size: clamp(34px, 4.6vw, 52px);
  font-weight: 800;
  background: var(--grad-2);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.stat-plus { font-size: clamp(20px, 2.4vw, 28px); font-weight: 700; color: var(--accent-2); }
.stat-label { display: block; margin-top: 6px; font-size: 14px; color: rgba(255, 255, 255, 0.6); letter-spacing: 2px; }

.scroll-hint {
  position: absolute;
  left: 50%; bottom: 26px;
  transform: translateX(-50%);
  width: 26px; height: 42px;
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-radius: 14px;
  display: flex; justify-content: center;
  padding-top: 8px;
}
.scroll-hint span {
  width: 4px; height: 9px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.7);
  animation: scrollDown 1.8s infinite;
}
@keyframes scrollDown {
  0% { transform: translateY(0); opacity: 1; }
  70% { transform: translateY(12px); opacity: 0; }
  100% { transform: translateY(0); opacity: 0; }
}

/* ===================== 通用区块 ===================== */
.section { padding: 110px 0; }
.section-alt { background: var(--bg-alt); }

.section-head { text-align: center; margin-bottom: 64px; }
.section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 4px;
  color: var(--primary);
  background: rgba(79, 140, 255, 0.1);
  padding: 6px 16px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.section-title { font-size: clamp(30px, 4vw, 44px); font-weight: 800; margin-bottom: 14px; letter-spacing: 1px; }
.section-desc { color: var(--ink-2); font-size: 16px; }

/* ===================== 关于我们 ===================== */
.about-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 80px;
}
.about-text p { color: var(--ink-2); margin-bottom: 18px; font-size: 16px; }
.about-points { margin: 26px 0 32px; }
.about-points li { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; color: var(--ink-2); }
.check {
  flex: 0 0 auto;
  width: 22px; height: 22px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: rgba(79, 140, 255, 0.12);
  color: var(--primary);
  font-size: 13px;
  font-weight: 700;
}

.about-visual { position: relative; display: flex; justify-content: center; }
.viz-card {
  position: relative;
  width: min(420px, 100%);
  aspect-ratio: 1;
  display: grid; place-items: center;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, rgba(79, 140, 255, 0.12), rgba(124, 92, 255, 0.05) 60%, transparent);
}
.viz-orb { position: relative; display: grid; place-items: center; }
.viz-core {
  width: 108px; height: 108px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--grad);
  color: #fff;
  font-size: 30px;
  font-weight: 800;
  box-shadow: 0 16px 40px rgba(99, 102, 241, 0.45);
  z-index: 2;
  animation: corePulse 4s ease-in-out infinite;
}
@keyframes corePulse {
  0%, 100% { box-shadow: 0 16px 40px rgba(99, 102, 241, 0.45), 0 0 0 0 rgba(99, 102, 241, 0.35); }
  50% { box-shadow: 0 16px 40px rgba(99, 102, 241, 0.45), 0 0 0 26px rgba(99, 102, 241, 0); }
}
.ring {
  position: absolute;
  border-radius: 50%;
  border: 1.5px dashed rgba(79, 140, 255, 0.35);
  animation: spin 26s linear infinite;
}
.ring-1 { width: 210px; height: 210px; }
.ring-2 { width: 290px; height: 290px; border-color: rgba(124, 92, 255, 0.3); animation-duration: 38s; animation-direction: reverse; }
.ring-3 { width: 370px; height: 370px; border-color: rgba(0, 212, 255, 0.25); animation-duration: 52s; }
@keyframes spin { to { transform: rotate(360deg); } }

.viz-node {
  position: absolute;
  padding: 8px 18px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
  white-space: nowrap;
  animation: nodeFloat 5s ease-in-out infinite;
}
.viz-node-1 { top: 6%; left: 6%; animation-delay: 0s; }
.viz-node-2 { top: 14%; right: 2%; animation-delay: 0.8s; }
.viz-node-3 { bottom: 12%; left: 2%; animation-delay: 1.4s; }
.viz-node-4 { bottom: 4%; right: 8%; animation-delay: 2s; }
@keyframes nodeFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.milestones {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.milestone {
  text-align: center;
  padding: 36px 24px;
  border-radius: var(--radius);
  background: var(--bg-alt);
  border: 1px solid var(--line);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.milestone:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.milestone-year {
  display: inline-block;
  font-size: 20px;
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 8px;
}
.milestone p { color: var(--ink-2); font-size: 15px; }

/* ===================== 核心业务 ===================== */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}
.service-card {
  padding: 36px 30px;
  border-radius: var(--radius);
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
}
.service-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.service-icon {
  width: 62px; height: 62px;
  display: grid; place-items: center;
  font-size: 28px;
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(79, 140, 255, 0.12), rgba(124, 92, 255, 0.12));
  margin-bottom: 22px;
}
.service-card h3 { font-size: 20px; margin-bottom: 12px; }
.service-card p { color: var(--ink-2); font-size: 15px; margin-bottom: 20px; }
.card-link { font-size: 14px; font-weight: 600; color: var(--primary); }
.card-link:hover { color: var(--primary-dark); }

/* ===================== 技术优势 ===================== */
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.adv-card {
  padding: 34px 26px;
  border-radius: var(--radius);
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s ease, box-shadow 0.35s ease;
}
.adv-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }
.adv-num {
  font-size: 34px;
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  opacity: 0.85;
  margin-bottom: 14px;
}
.adv-card h3 { font-size: 18px; margin-bottom: 10px; }
.adv-card p { color: var(--ink-2); font-size: 14px; margin-bottom: 22px; }
.adv-bar {
  height: 8px;
  border-radius: 8px;
  background: #eef1fb;
  overflow: hidden;
  margin-bottom: 8px;
}
.adv-bar span {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 8px;
  background: var(--grad);
  transition: width 1.2s ease 0.2s;
}
.adv-card.in-view .adv-bar span { width: var(--w); }
.adv-card small { color: var(--ink-3); font-size: 12px; letter-spacing: 2px; }

/* ===================== 产品方案 ===================== */
.product-tabs {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 44px;
}
.tab-btn {
  padding: 10px 26px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink-2);
  font-size: 14px;
  font-weight: 600;
  transition: all 0.3s ease;
}
.tab-btn:hover { border-color: var(--primary); color: var(--primary); }
.tab-btn.active {
  background: var(--grad);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 8px 20px rgba(99, 102, 241, 0.35);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}
.product-card {
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s ease, box-shadow 0.35s ease;
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.4s ease, transform 0.4s ease, box-shadow 0.35s ease;
}
.product-card.show { opacity: 1; transform: translateY(0); }
.product-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }
.product-thumb {
  height: 150px;
  display: grid; place-items: center;
  color: #fff;
  font-size: 40px;
  font-weight: 800;
  letter-spacing: 6px;
}
.thumb-1 { background: linear-gradient(135deg, #4f8cff, #3a6ef0); }
.thumb-2 { background: linear-gradient(135deg, #7c5cff, #5b3df0); }
.thumb-3 { background: linear-gradient(135deg, #00c2ff, #4f8cff); }
.thumb-4 { background: linear-gradient(135deg, #b45cff, #7c5cff); }
.thumb-5 { background: linear-gradient(135deg, #34d399, #0ea5e9); }
.thumb-6 { background: linear-gradient(135deg, #f59e0b, #ef4444); }
.product-body { padding: 24px; }
.product-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--primary);
  background: rgba(79, 140, 255, 0.1);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
}
.product-body h3 { font-size: 18px; margin-bottom: 8px; }
.product-body p { color: var(--ink-2); font-size: 14px; }

/* ===================== 客户之声 ===================== */
.testimonials {
  background:
    radial-gradient(900px 500px at 85% 0%, rgba(79, 140, 255, 0.08), transparent),
    var(--bg);
}
.testi-slider { max-width: 760px; margin: 0 auto; overflow: hidden; }
.testi-track { display: flex; transition: transform 0.5s ease; }
.testi-slide { flex: 0 0 100%; text-align: center; padding: 10px 6px; }
.testi-slide blockquote {
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.9;
  color: var(--ink);
  font-weight: 500;
  margin-bottom: 26px;
}
.testi-slide blockquote::before { content: "“"; display: block; font-size: 56px; line-height: 0.6; color: var(--primary); opacity: 0.5; margin-bottom: 14px; }
.testi-slide figcaption strong { display: block; font-size: 16px; }
.testi-slide figcaption span { color: var(--ink-3); font-size: 14px; }
.testi-nav { display: flex; align-items: center; justify-content: center; gap: 20px; margin-top: 30px; }
.testi-btn {
  width: 42px; height: 42px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
  font-size: 16px;
  transition: all 0.3s ease;
}
.testi-btn:hover { background: var(--grad); color: #fff; border-color: transparent; }
.testi-dots { display: flex; gap: 8px; }
.testi-dots span {
  width: 8px; height: 8px;
  border-radius: 8px;
  background: var(--line);
  transition: all 0.3s ease;
  cursor: pointer;
}
.testi-dots span.active { width: 26px; background: var(--grad); }

/* ===================== 联系我们 ===================== */
.section-contact { background: var(--bg-alt); }
.contact-grid {
  display: grid;
  grid-template-columns: 1fr;
  justify-items: center;
}
.contact-info { text-align: center; max-width: 720px; }
.contact-info .section-title { margin-top: 0; }
.contact-info > p { color: var(--ink-2); margin-bottom: 44px; }
.contact-list {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
  width: 100%;
  max-width: 980px;
}
.contact-list li {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  text-align: center;
  padding: 30px 20px;
  border-radius: var(--radius);
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.contact-list li:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.contact-icon {
  flex: 0 0 auto;
  width: 52px; height: 52px;
  display: grid; place-items: center;
  font-size: 24px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(79, 140, 255, 0.12), rgba(124, 92, 255, 0.12));
}
.contact-list strong { display: block; font-size: 16px; margin-bottom: 4px; }
.contact-list span:last-child { color: var(--ink-2); font-size: 14px; line-height: 1.6; word-break: break-all; }

/* ===================== 页脚 ===================== */
.footer { background: #0b1120; color: #cbd5e1; padding-top: 72px; }
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 48px;
}
.footer .brand-text strong { color: #fff; }
.footer .brand-text small { color: rgba(255, 255, 255, 0.5); }
.footer-brand p { margin-top: 18px; font-size: 14px; color: #94a3b8; line-height: 1.8; }
.footer-col h4 { color: #fff; font-size: 16px; margin-bottom: 18px; }
.footer-col a, .footer-col span { display: block; color: #94a3b8; font-size: 14px; margin-bottom: 10px; transition: color 0.25s ease; }
.footer-col a:hover { color: var(--primary); }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 20px 0;
}
.footer-bottom .container { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.footer-bottom span { font-size: 13px; color: #64748b; }
.footer-icp { font-size: 13px; color: #64748b; }
.footer-icp:hover { color: #cbd5e1; }

/* ===================== 回到顶部 ===================== */
.back-top {
  position: fixed;
  right: 26px; bottom: 26px;
  width: 46px; height: 46px;
  border-radius: 50%;
  border: none;
  background: var(--grad);
  color: #fff;
  font-size: 18px;
  box-shadow: 0 10px 24px rgba(99, 102, 241, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: all 0.35s ease;
  z-index: 900;
}
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0); }
.back-top:hover { transform: translateY(-3px); }

/* ===================== 滚动入场动画 ===================== */
.reveal {
  opacity: 0;
  transform: translateY(34px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.in-view { opacity: 1; transform: translateY(0); }

/* ===================== 响应式 ===================== */
@media (max-width: 1024px) {
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid { grid-template-columns: 1fr; gap: 48px; }
  .contact-list { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .section { padding: 80px 0; }
  .nav-links, .nav-cta {
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    flex-direction: column;
    align-items: flex-start;
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(16px);
    padding: 20px 6%;
    gap: 6px;
    box-shadow: var(--shadow-md);
    transform: translateY(-16px);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
  }
  .nav-links { display: flex; }
  .nav-cta { position: static; margin-top: 14px; width: fit-content; }
  .nav-links.open { transform: translateY(0); opacity: 1; visibility: visible; }
  .nav-links a { color: var(--ink-2) !important; width: 100%; padding: 12px 0; border-bottom: 1px solid var(--line); }
  .nav-toggle { display: flex; }

  .services-grid, .adv-grid, .products-grid { grid-template-columns: 1fr; }
  .milestones { grid-template-columns: 1fr; }
  .contact-list { grid-template-columns: 1fr; max-width: 420px; }
  .hero-stats { gap: 28px; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .scroll-hint { display: none; }
}

@media (max-width: 480px) {
  .hero-actions .btn { width: 100%; }
}