/* ============================================================
   上海行于时科技有限公司 — 官网样式
   主色：蓝 #0A3D91 / 白 #FFFFFF / 红 #E63946
   ============================================================ */

:root {
  --blue-950: #041A3C;
  --blue-900: #06234E;
  --blue-800: #0A3D91;
  --blue-700: #0E4BC4;
  --blue-600: #1663E8;
  --blue-500: #3D8BFF;
  --blue-100: #E8F0FE;
  --blue-50: #F4F8FF;
  --red-600: #E63946;
  --red-500: #EF4B57;
  --red-100: #FDEBEC;
  --white: #FFFFFF;
  --ink: #0F1E3D;
  --gray-700: #34405F;
  --gray-500: #64748B;
  --gray-300: #CBD5E1;
  --gray-200: #E2E8F0;
  --gray-100: #F1F5F9;
  --radius: 16px;
  --radius-lg: 22px;
  --shadow-sm: 0 2px 10px rgba(10, 61, 145, 0.08);
  --shadow-md: 0 12px 32px rgba(10, 61, 145, 0.14);
  --shadow-lg: 0 24px 60px rgba(6, 35, 78, 0.22);
  --header-h: 78px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
}

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

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 12px); }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

.container { width: min(1180px, 92%); margin: 0 auto; }

::selection { background: var(--blue-600); color: #fff; }

::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--gray-100); }
::-webkit-scrollbar-thumb { background: linear-gradient(var(--blue-600), var(--blue-800)); border-radius: 8px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 26px; border-radius: 999px;
  font-size: 15px; font-weight: 600; letter-spacing: 0.02em;
  border: 2px solid transparent;
  transition: all 0.28s ease;
  white-space: nowrap;
}
.btn-sm { padding: 8px 18px; font-size: 13.5px; }
.btn-lg { padding: 15px 34px; font-size: 16px; }
.btn-block { width: 100%; }

.btn-primary { background: linear-gradient(135deg, var(--blue-600), var(--blue-800)); color: #fff; box-shadow: 0 8px 22px rgba(14, 75, 196, 0.32); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(14, 75, 196, 0.42); }

.btn-ghost { border-color: rgba(255,255,255,0.55); color: #fff; background: rgba(255,255,255,0.06); backdrop-filter: blur(4px); }
.btn-ghost:hover { border-color: #fff; background: rgba(255,255,255,0.14); transform: translateY(-2px); }
.btn-ghost .arrow { transition: transform 0.28s ease; }
.btn-ghost:hover .arrow { transform: translateX(5px); }

.btn-white { background: #fff; color: var(--blue-800); box-shadow: 0 10px 28px rgba(0,0,0,0.18); }
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 16px 34px rgba(0,0,0,0.24); }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  height: var(--header-h);
  transition: all 0.3s ease;
}
.site-header.scrolled {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(14px);
  box-shadow: 0 4px 24px rgba(6, 35, 78, 0.10);
}
.header-inner { height: var(--header-h); display: flex; align-items: center; justify-content: space-between; gap: 24px; }

.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark { display: grid; place-items: center; }
.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-text strong { font-size: 19px; color: var(--blue-800); letter-spacing: 0.05em; }
.brand-text small { font-size: 9.5px; color: var(--gray-500); letter-spacing: 0.14em; font-weight: 600; }
.site-header:not(.scrolled) .brand-text strong { color: #fff; }
.site-header:not(.scrolled) .brand-text small { color: rgba(255,255,255,0.65); }

.main-nav { display: flex; gap: 6px; }
.nav-link {
  position: relative; padding: 8px 14px; border-radius: 8px;
  font-size: 15px; color: var(--gray-700); font-weight: 500;
  transition: color 0.25s ease;
}
.site-header:not(.scrolled) .nav-link { color: rgba(255,255,255,0.86); }
.nav-link::after {
  content: ""; position: absolute; left: 14px; right: 14px; bottom: 2px;
  height: 2.5px; border-radius: 2px; background: var(--red-600);
  transform: scaleX(0); transform-origin: left; transition: transform 0.3s ease;
}
.nav-link:hover { color: var(--blue-600); }
.nav-link.active::after, .nav-link:hover::after { transform: scaleX(1); }
.site-header:not(.scrolled) .nav-link:hover, .site-header:not(.scrolled) .nav-link.active { color: #fff; }

.header-actions { display: flex; align-items: center; gap: 12px; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; padding: 10px; }
.nav-toggle span { width: 24px; height: 2.5px; border-radius: 2px; background: var(--blue-800); transition: all 0.3s ease; }
.site-header:not(.scrolled) .nav-toggle span { background: #fff; }
.nav-toggle.open span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex; align-items: center;
  background:
    radial-gradient(1100px 560px at 82% -10%, rgba(61,139,255,0.34), transparent 60%),
    radial-gradient(900px 520px at 8% 110%, rgba(230,57,70,0.18), transparent 55%),
    linear-gradient(160deg, var(--blue-950) 0%, var(--blue-900) 46%, var(--blue-800) 100%);
  color: #fff;
  overflow: hidden;
  padding: calc(var(--header-h) + 40px) 0 90px;
}
.hero-grid-bg {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 80% at 50% 40%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 50% 40%, #000 30%, transparent 75%);
  pointer-events: none;
}
.hero-canvas { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; opacity: 0.75; }

.hero-inner { position: relative; z-index: 2; display: grid; grid-template-columns: 1.08fr 0.92fr; gap: 56px; align-items: center; }

.badge {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 7px 16px; border-radius: 999px;
  background: rgba(255,255,255,0.10);
  border: 1px solid rgba(255,255,255,0.22);
  font-size: 13.5px; font-weight: 600; letter-spacing: 0.06em;
  backdrop-filter: blur(6px);
  margin-bottom: 26px;
}
.badge-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--red-500);
  box-shadow: 0 0 0 0 rgba(230,57,70,0.55);
  animation: pulse 1.8s infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(230,57,70,0.55); }
  70% { box-shadow: 0 0 0 10px rgba(230,57,70,0); }
  100% { box-shadow: 0 0 0 0 rgba(230,57,70,0); }
}

.hero h1 {
  font-size: clamp(38px, 5vw, 60px);
  line-height: 1.18; font-weight: 800; letter-spacing: 0.02em;
  margin-bottom: 22px;
}
.hero h1 .accent {
  color: var(--red-500);
  position: relative;
}
.hero h1 .accent::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: 2px; height: 10px;
  background: rgba(230,57,70,0.28); z-index: -1; border-radius: 4px;
}
.hero-sub {
  font-size: 16.5px; color: rgba(255,255,255,0.82);
  max-width: 560px; margin-bottom: 34px;
}
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 46px; }

.hero-stats { display: flex; gap: 0; }
.hero-stats .stat { padding: 0 30px; border-left: 1px solid rgba(255,255,255,0.18); }
.hero-stats .stat:first-child { padding-left: 0; border-left: 0; }
.hero-stats strong { display: block; font-size: 32px; font-weight: 800; color: #fff; line-height: 1.2; }
.hero-stats strong span { font-variant-numeric: tabular-nums; }
.hero-stats .stat span:last-child { font-size: 13.5px; color: rgba(255,255,255,0.66); }

/* Hero 视觉区 */
.hero-visual { display: flex; justify-content: center; }
.visual-card {
  position: relative;
  width: min(440px, 100%);
  aspect-ratio: 1 / 1;
  display: grid; place-items: center;
}
.orbit {
  position: absolute; border-radius: 50%;
  border: 1.5px dashed rgba(255,255,255,0.28);
  animation: spin 40s linear infinite;
}
.orbit-1 { width: 100%; height: 100%; }
.orbit-2 { width: 74%; height: 74%; border-style: solid; border-color: rgba(230,57,70,0.4); animation-duration: 26s; animation-direction: reverse; }
@keyframes spin { to { transform: rotate(360deg); } }

.arm-svg { width: 88%; height: auto; filter: drop-shadow(0 24px 40px rgba(0,0,0,0.35)); }

.float-chip {
  position: absolute;
  display: inline-flex; align-items: center; gap: 7px;
  padding: 9px 15px; border-radius: 12px;
  background: rgba(255,255,255,0.94);
  color: var(--blue-800); font-size: 13.5px; font-weight: 600;
  box-shadow: 0 12px 28px rgba(4, 26, 60, 0.35);
  animation: float 5s ease-in-out infinite;
}
.chip-1 { top: 9%; left: -2%; animation-delay: 0s; }
.chip-2 { top: 40%; right: -6%; animation-delay: 1.2s; }
.chip-3 { bottom: 12%; left: 6%; animation-delay: 2.2s; }
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.scan-line {
  position: absolute; left: 6%; right: 6%; height: 2px;
  background: linear-gradient(90deg, transparent, var(--red-500), transparent);
  border-radius: 2px;
  animation: scan 4.5s ease-in-out infinite;
  opacity: 0.85;
}
@keyframes scan {
  0% { top: 12%; opacity: 0; }
  12% { opacity: 0.9; }
  88% { opacity: 0.9; }
  100% { top: 88%; opacity: 0; }
}

.hero-wave {
  position: absolute; left: 0; right: 0; bottom: -1px; height: 70px;
  background: #fff;
  clip-path: polygon(0 100%, 100% 100%, 100% 55%, 75% 30%, 50% 55%, 25% 30%, 0 55%);
  opacity: 1;
}

/* ---------- 行业条幅 ---------- */
.marquee-section { background: var(--white); padding: 26px 0; border-bottom: 1px solid var(--gray-100); }
.marquee-label { text-align: center; font-size: 13px; color: var(--gray-500); letter-spacing: 0.3em; margin-bottom: 16px; }
.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; gap: 18px; width: max-content; animation: marquee 30s linear infinite; }
.marquee-track span {
  padding: 8px 22px; border-radius: 999px;
  background: var(--blue-50); border: 1px solid var(--blue-100);
  color: var(--blue-800); font-size: 14px; font-weight: 600; white-space: nowrap;
}
.marquee-track span:nth-child(even) { background: var(--red-100); border-color: #F8D6D9; color: var(--red-600); }
@keyframes marquee { to { transform: translateX(-50%); } }

/* ---------- 通用 Section ---------- */
.section { padding: 100px 0; }
.section-head { max-width: 640px; margin: 0 auto 58px; text-align: center; }
.section-tag {
  display: inline-block; padding: 6px 16px; border-radius: 999px;
  background: var(--blue-100); color: var(--blue-700);
  font-size: 13px; font-weight: 700; letter-spacing: 0.14em;
  margin-bottom: 16px;
}
.section-head h2 { font-size: clamp(28px, 3.6vw, 40px); font-weight: 800; letter-spacing: 0.02em; margin-bottom: 14px; }
.section-head p { color: var(--gray-500); font-size: 16px; }

/* ---------- 关于我们 ---------- */
.about { background: linear-gradient(180deg, #fff 0%, var(--blue-50) 100%); }
.about-grid { display: grid; grid-template-columns: 1fr 1.05fr; gap: 60px; align-items: center; margin-bottom: 70px; }

.about-media { position: relative; }
.about-panel {
  position: relative;
  aspect-ratio: 1 / 1;
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, var(--blue-800), var(--blue-950));
  display: grid; place-items: center;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.about-panel::before {
  content: ""; position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 40px 40px;
}
.about-mark {
  position: absolute; top: 8%; left: 8%;
  font-size: clamp(90px, 14vw, 150px); font-weight: 800;
  color: rgba(255,255,255,0.08); line-height: 1;
  user-select: none;
}
.about-line { position: relative; z-index: 1; width: 88%; }
.about-chips {
  position: absolute; bottom: 7%; left: 0; right: 0;
  display: flex; justify-content: center; gap: 10px; flex-wrap: wrap;
}
.about-chips span {
  padding: 6px 14px; border-radius: 999px;
  background: rgba(255,255,255,0.12); border: 1px solid rgba(255,255,255,0.22);
  color: #fff; font-size: 12.5px; font-weight: 600; backdrop-filter: blur(4px);
}
.about-float-card {
  position: absolute; right: -22px; bottom: 34px;
  padding: 18px 26px; border-radius: var(--radius);
  background: #fff; box-shadow: var(--shadow-md);
  border-left: 4px solid var(--red-600);
  display: flex; flex-direction: column;
}
.about-float-card strong { font-size: 28px; color: var(--blue-800); line-height: 1.2; }
.about-float-card span { font-size: 13px; color: var(--gray-500); }

.about-copy h3 { font-size: 25px; font-weight: 800; margin-bottom: 18px; line-height: 1.4; }
.about-copy p { color: var(--gray-700); margin-bottom: 22px; }
.check-list { margin-bottom: 30px; }
.check-list li {
  position: relative; padding-left: 30px; margin-bottom: 12px;
  color: var(--gray-700); font-size: 15px;
}
.check-list li::before {
  content: "✓";
  position: absolute; left: 0; top: 1px;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--blue-600); color: #fff;
  font-size: 12px; font-weight: 700;
  display: grid; place-items: center;
}

.mvv-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.mvv-card {
  padding: 36px 30px; border-radius: var(--radius-lg);
  background: #fff; border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: all 0.3s ease;
}
.mvv-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: var(--blue-100); }
.mvv-ic {
  display: grid; place-items: center;
  width: 58px; height: 58px; margin: 0 auto 18px; border-radius: 16px;
  background: linear-gradient(135deg, var(--blue-600), var(--blue-800));
  box-shadow: 0 10px 22px rgba(14, 75, 196, 0.30);
}
.mvv-ic.mvv-red { background: linear-gradient(135deg, #F05763, var(--red-600)); box-shadow: 0 10px 22px rgba(230,57,70,0.30); }
.mvv-card h4 { font-size: 19px; font-weight: 700; margin-bottom: 10px; color: var(--blue-900); }
.mvv-card p { color: var(--gray-500); font-size: 14.5px; }

/* ---------- 核心业务 ---------- */
.business { background: var(--white); }
.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.card {
  position: relative;
  padding: 34px 28px 30px; border-radius: var(--radius-lg);
  background: var(--white);
  border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
  transition: all 0.32s ease;
  overflow: hidden;
}
.card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--blue-600), var(--red-600));
  transform: scaleX(0); transform-origin: left; transition: transform 0.32s ease;
}
.card:hover { transform: translateY(-8px); box-shadow: var(--shadow-md); border-color: transparent; }
.card:hover::before { transform: scaleX(1); }
.card-ic {
  display: grid; place-items: center;
  width: 56px; height: 56px; border-radius: 14px;
  background: var(--blue-50); border: 1px solid var(--blue-100);
  margin-bottom: 20px; transition: all 0.3s ease;
}
.card:hover .card-ic { background: var(--blue-800); border-color: var(--blue-800); }
.card:hover .card-ic svg path, .card:hover .card-ic svg circle, .card:hover .card-ic svg rect, .card:hover .card-ic svg ellipse { stroke: #fff; }
.card h3 { font-size: 18.5px; font-weight: 700; margin-bottom: 10px; color: var(--blue-900); }
.card p { color: var(--gray-500); font-size: 14.5px; margin-bottom: 18px; }
.card-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.card-tags span {
  padding: 4px 12px; border-radius: 999px;
  background: var(--gray-100); color: var(--gray-700);
  font-size: 12px; font-weight: 600;
}
.card:hover .card-tags span:nth-child(1) { background: var(--blue-100); color: var(--blue-700); }
.card:hover .card-tags span:nth-child(2) { background: var(--red-100); color: var(--red-600); }

/* ---------- 解决方案 ---------- */
.solutions { background: linear-gradient(180deg, var(--blue-50) 0%, #fff 100%); }
.sol-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.sol-card {
  padding: 30px 26px; border-radius: var(--radius-lg);
  background: #fff; border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
  transition: all 0.32s ease;
  display: flex; flex-direction: column;
}
.sol-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-md); }
.sol-card.sol-blue { border-top: 4px solid var(--blue-600); }
.sol-card.sol-red { border-top: 4px solid var(--red-600); }
.sol-head { display: flex; align-items: center; gap: 14px; margin-bottom: 18px; }
.sol-ic {
  display: grid; place-items: center;
  width: 46px; height: 46px; border-radius: 12px;
  background: var(--blue-50); border: 1px solid var(--blue-100); flex-shrink: 0;
}
.sol-red .sol-ic { background: var(--red-100); border-color: #F8D6D9; }
.sol-head h3 { font-size: 18px; font-weight: 700; color: var(--blue-900); }
.sol-card ul { margin-bottom: 22px; }
.sol-card li {
  position: relative; padding-left: 20px;
  font-size: 14px; color: var(--gray-700); margin-bottom: 9px;
}
.sol-card li::before { content: "▸"; position: absolute; left: 0; color: var(--red-600); font-weight: 700; }
.sol-link { margin-top: auto; font-size: 14px; font-weight: 700; color: var(--blue-600); transition: color 0.25s ease; }
.sol-link:hover { color: var(--red-600); }

/* ---------- 合作流程 ---------- */
.process { background: var(--white); }
.step-row { display: flex; align-items: stretch; justify-content: space-between; gap: 12px; }
.step {
  flex: 1; padding: 30px 22px; border-radius: var(--radius-lg);
  background: var(--blue-50); border: 1px solid var(--blue-100);
  text-align: center;
  transition: all 0.3s ease;
}
.step:hover { transform: translateY(-6px); box-shadow: var(--shadow-sm); background: #fff; }
.step-num {
  display: inline-grid; place-items: center;
  width: 44px; height: 44px; border-radius: 50%;
  background: linear-gradient(135deg, var(--blue-600), var(--blue-800));
  color: #fff; font-weight: 800; font-size: 15px;
  margin-bottom: 14px;
  box-shadow: 0 8px 18px rgba(14,75,196,0.28);
}
.step h4 { font-size: 16.5px; font-weight: 700; color: var(--blue-900); margin-bottom: 6px; }
.step p { font-size: 13px; color: var(--gray-500); }
.step-arrow { align-self: center; color: var(--red-600); font-size: 22px; font-weight: 800; flex-shrink: 0; }

/* ---------- CTA 横幅 ---------- */
.cta-band {
  background:
    radial-gradient(700px 320px at 15% 120%, rgba(61,139,255,0.35), transparent 60%),
    radial-gradient(600px 300px at 90% -40%, rgba(230,57,70,0.30), transparent 55%),
    linear-gradient(120deg, var(--blue-800), var(--blue-900));
  color: #fff;
}
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 30px; padding: 70px 0; flex-wrap: wrap; }
.cta-inner h2 { font-size: clamp(24px, 3vw, 34px); font-weight: 800; margin-bottom: 8px; }
.cta-inner p { color: rgba(255,255,255,0.75); font-size: 15.5px; }

/* ---------- 联系我们 ---------- */
.contact { background: var(--white); }
.contact-grid { max-width: 720px; margin: 0 auto; }
.contact-info { display: flex; flex-direction: column; align-items: center; }
.ci-item {
  display: inline-flex; align-items: center; gap: 18px;
  padding: 24px 38px; border-radius: var(--radius-lg);
  background: #fff; border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}
.ci-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--blue-100); }
.ci-ic {
  display: grid; place-items: center; flex-shrink: 0;
  width: 52px; height: 52px; border-radius: 14px;
  background: var(--blue-50); border: 1px solid var(--blue-100);
}
.ci-item h4 { font-size: 16px; font-weight: 700; color: var(--blue-900); margin-bottom: 4px; }
.ci-item p { font-size: 17px; color: var(--blue-800); font-weight: 700; }
.ci-lead {
  font-size: 15px; color: var(--gray-700); line-height: 1.9;
  max-width: 560px; margin: 0 auto 36px; padding: 22px 26px; border-radius: var(--radius);
  background: var(--blue-50); border: 1px solid var(--blue-100);
  border-left: 4px solid var(--red-600);
  text-align: left;
}

/* ---------- 页脚 ---------- */
.footer { background: var(--blue-950); color: #fff; padding: 70px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.2fr; gap: 44px; padding-bottom: 46px; }
.footer .brand-text strong { color: #fff; }
.footer .brand-text small { color: rgba(255,255,255,0.55); }
.footer-brand p { margin-top: 18px; font-size: 14px; color: rgba(255,255,255,0.6); max-width: 300px; }
.footer-col h4 { font-size: 15.5px; font-weight: 700; margin-bottom: 18px; position: relative; padding-bottom: 10px; }
.footer-col h4::after { content: ""; position: absolute; left: 0; bottom: 0; width: 26px; height: 3px; border-radius: 2px; background: var(--red-600); }
.footer-col a { display: block; font-size: 14px; color: rgba(255,255,255,0.62); margin-bottom: 11px; transition: all 0.25s ease; }
.footer-col a:hover { color: #fff; padding-left: 6px; }
.footer-col p { font-size: 14px; color: rgba(255,255,255,0.62); margin-bottom: 11px; }
.footer-bottom .beian-link { color: rgba(255,255,255,0.5); transition: color 0.25s ease; }
.footer-bottom .beian-link:hover { color: #fff; }

.footer-bottom {
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
  padding: 20px 0; border-top: 1px solid rgba(255,255,255,0.10);
  font-size: 13px; color: rgba(255,255,255,0.5);
}
.back-top {
  display: grid; place-items: center;
  width: 40px; height: 40px; border-radius: 10px;
  background: linear-gradient(135deg, var(--blue-600), var(--blue-800));
  color: #fff; font-size: 17px; font-weight: 700;
  transition: all 0.25s ease;
}
.back-top:hover { transform: translateY(-4px); background: linear-gradient(135deg, #F05763, var(--red-600)); }

/* ---------- 滚动显现动画 ---------- */
:where(.reveal) { opacity: 0; transform: translateY(30px); transition: opacity 0.75s ease, transform 0.75s ease; }
:where(.reveal).in-view { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; text-align: center; }
  .hero-sub { margin-inline: auto; }
  .hero-cta, .hero-stats { justify-content: center; }
  .hero-stats .stat { padding: 0 22px; }
  .hero { padding-top: calc(var(--header-h) + 56px); }
  .about-grid { grid-template-columns: 1fr; gap: 50px; }
  .about-float-card { right: 6px; }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .sol-grid { grid-template-columns: repeat(2, 1fr); }
  .step-row { flex-wrap: wrap; }
  .step { flex: 1 1 40%; }
  .step-arrow { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  :root { --header-h: 66px; }
  .main-nav {
    position: fixed; top: var(--header-h); left: 0; right: 0;
    flex-direction: column; gap: 4px;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(14px);
    padding: 16px 5% 22px;
    box-shadow: 0 16px 36px rgba(6,35,78,0.14);
    transform: translateY(-130%); opacity: 0;
    transition: all 0.35s ease;
    border-radius: 0 0 18px 18px;
  }
  .main-nav.open { transform: none; opacity: 1; }
  .nav-link { padding: 12px 14px; color: var(--gray-700) !important; font-size: 16px; }
  .nav-link::after { display: none; }
  .nav-link.active { background: var(--blue-50); color: var(--blue-700) !important; }
  .nav-toggle { display: flex; }
  .header-cta { display: none; }
  .hero { min-height: auto; }
  .hero-stats strong { font-size: 26px; }
  .hero-stats .stat { padding: 0 14px; }
  .visual-card { width: min(320px, 90%); }
  .float-chip { font-size: 12px; padding: 7px 12px; }
  .section { padding: 72px 0; }
  .section-head { margin-bottom: 44px; }
  .mvv-grid { grid-template-columns: 1fr; }
  .card-grid { grid-template-columns: 1fr; }
  .sol-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .cta-inner { justify-content: center; text-align: center; }
  .footer-bottom { flex-direction: column-reverse; }
  .about-float-card { position: static; margin-top: 18px; width: max-content; }
}

@media (max-width: 480px) {
  .hero-cta .btn { width: 100%; }
  .hero-stats { flex-wrap: wrap; gap: 16px 0; }
  .hero-stats .stat { border-left: 0; padding: 0 14px; }
}

/* ============================================================
   语言切换 / i18n（中英双语）
   ============================================================ */
html.i18n-pending body { visibility: hidden; }

.lang-switch {
  display: inline-flex;
  align-items: center;
  padding: 2px;
  border-radius: 999px;
  border: 1px solid rgba(10, 61, 145, 0.22);
  background: rgba(10, 61, 145, 0.06);
}
.lang-btn {
  display: inline-block;
  border: 0;
  background: none;
  cursor: pointer;
  text-decoration: none;
  font-family: inherit;
  font-size: 12.5px;
  line-height: 1;
  padding: 7px 11px;
  border-radius: 999px;
  color: var(--blue-800);
  transition: background 0.2s ease, color 0.2s ease;
}
.lang-btn:hover { background: rgba(10, 61, 145, 0.08); }
.lang-btn.active { background: var(--blue-600); color: #fff; }
.lang-btn.active:hover { background: var(--blue-700); }

.site-header:not(.scrolled) .lang-switch {
  border-color: rgba(255, 255, 255, 0.35);
  background: rgba(255, 255, 255, 0.08);
}
.site-header:not(.scrolled) .lang-btn { color: rgba(255, 255, 255, 0.9); }
.site-header:not(.scrolled) .lang-btn:hover { background: rgba(255, 255, 255, 0.16); }
.site-header:not(.scrolled) .lang-btn.active { background: #fff; color: var(--blue-800); }

@media (max-width: 768px) {
  .lang-btn { padding: 6px 9px; font-size: 12px; }
}