/* ============================================================
   揽智科技 · 设计语言（参考 deepseek.com 风格）
   白底 / 品牌蓝 / 大留白 / 圆角细边框 / 轻动效
   ============================================================ */

:root {
  --primary: #4d6bfe;
  --primary-dark: #3b56e0;
  --primary-soft: #eef2ff;
  --violet: #7c5cff;
  --ink: #0b1530;
  --body: #454c5c;
  --muted: #7a8299;
  --bg: #ffffff;
  --bg-alt: #f6f8fd;
  --border: #e7eaf4;
  --footer-bg: #0a1128;
  --radius: 16px;
  --radius-sm: 12px;
  --shadow-sm: 0 1px 2px rgba(16, 24, 64, 0.05);
  --shadow-md: 0 12px 32px rgba(77, 107, 254, 0.12);
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --tr: all 0.25s ease;
}

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

html { scroll-behavior: smooth; }

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

img { max-width: 100%; display: block; }
a { color: var(--primary); text-decoration: none; }

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 导航 ---------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0.02em;
}

.nav-brand svg { display: block; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 15px;
  font-weight: 500;
  color: var(--body);
  transition: var(--tr);
  position: relative;
  padding: 4px 0;
}

.nav-links a:hover { color: var(--primary); }

.nav-links a.active {
  color: var(--primary);
  font-weight: 600;
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -3px;
  width: 16px;
  height: 3px;
  border-radius: 2px;
  transform: translateX(-50%);
  background: var(--primary);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  padding: 9px 20px;
  border-radius: 999px;
  background: var(--primary);
  color: #fff !important;
  font-size: 14px;
  font-weight: 600;
  transition: var(--tr);
}

.nav-cta:hover {
  background: var(--primary-dark);
  box-shadow: 0 6px 16px rgba(77, 107, 254, 0.35);
  transform: translateY(-1px);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--ink);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  transition: var(--tr);
  cursor: pointer;
  border: 1px solid transparent;
}

.btn svg { transition: transform 0.25s ease; }
.btn:hover svg { transform: translateX(3px); }

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
  box-shadow: 0 8px 22px rgba(77, 107, 254, 0.35);
  transform: translateY(-2px);
}

.btn-ghost {
  background: #fff;
  color: var(--ink);
  border-color: var(--border);
}

.btn-ghost:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.btn-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* ---------- 首页 Hero ---------- */
.hero {
  position: relative;
  padding: 120px 0 100px;
  text-align: center;
  overflow: hidden;
  background:
    radial-gradient(640px 320px at 15% 0%, rgba(77, 107, 254, 0.10), transparent 65%),
    radial-gradient(560px 300px at 85% 10%, rgba(124, 92, 255, 0.10), transparent 65%),
    linear-gradient(180deg, #f3f6ff 0%, #ffffff 80%);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(77, 107, 254, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(77, 107, 254, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(180deg, rgba(0,0,0,0.7), transparent 70%);
  -webkit-mask-image: linear-gradient(180deg, rgba(0,0,0,0.7), transparent 70%);
  pointer-events: none;
}

.hero .container { position: relative; z-index: 1; }

.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--border);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  box-shadow: var(--shadow-sm);
  margin-bottom: 28px;
}

.hero-kicker::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--violet));
}

.hero-title {
  font-size: 46px;
  line-height: 1.25;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
  max-width: 820px;
  margin: 0 auto 22px;
}

.gradient-text {
  background: linear-gradient(92deg, var(--primary) 10%, var(--violet) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead {
  font-size: 18px;
  color: var(--muted);
  max-width: 640px;
  margin: 0 auto 40px;
}

/* ---------- 数据统计条 ---------- */
.stats-strip {
  display: flex;
  justify-content: center;
  gap: 72px;
  margin-top: 64px;
  flex-wrap: wrap;
}

.stat { text-align: center; }

.stat-num {
  font-size: 30px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.stat-num em {
  font-style: normal;
  background: linear-gradient(92deg, var(--primary), var(--violet));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.stat-label {
  font-size: 13px;
  color: var(--muted);
  margin-top: 4px;
}

/* ---------- 通用区块 ---------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }

.section-head {
  text-align: center;
  max-width: 620px;
  margin: 0 auto 56px;
}

.section-kicker {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--primary);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-head h2 {
  font-size: 32px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin-bottom: 14px;
}

.section-head p { color: var(--muted); }

/* ---------- 卡片 ---------- */
.cards-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 28px;
  box-shadow: var(--shadow-sm);
  transition: var(--tr);
}

.card:hover {
  transform: translateY(-5px);
  border-color: rgba(77, 107, 254, 0.4);
  box-shadow: var(--shadow-md);
}

.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  background: var(--primary-soft);
  color: var(--primary);
  margin-bottom: 20px;
}

.card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 10px;
}

.card p { font-size: 15px; }

.feature-list {
  list-style: none;
  margin-top: 18px;
  border-top: 1px dashed var(--border);
  padding-top: 16px;
}

.feature-list li {
  position: relative;
  padding: 6px 0 6px 26px;
  font-size: 14px;
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--primary-soft)
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%234d6bfe' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6L9 17l-5-5'/%3E%3C/svg%3E")
    center / 10px no-repeat;
}

/* ---------- 客户展示 ---------- */
.clients-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.client-tile {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 132px;
  padding: 18px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: var(--tr);
}

.client-tile img {
  max-height: 100%;
  object-fit: contain;
  filter: grayscale(100%);
  opacity: 0.75;
  transition: var(--tr);
}

.client-tile:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.client-tile:hover img {
  filter: grayscale(0);
  opacity: 1;
}

/* ---------- 子页 Hero ---------- */
.page-hero {
  padding: 88px 0 64px;
  text-align: center;
  background:
    radial-gradient(560px 260px at 20% 0%, rgba(77, 107, 254, 0.09), transparent 65%),
    radial-gradient(480px 240px at 85% 15%, rgba(124, 92, 255, 0.08), transparent 65%),
    linear-gradient(180deg, #f3f6ff 0%, #ffffff 85%);
}

.page-hero h1 {
  font-size: 38px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin-bottom: 16px;
}

.page-hero p {
  font-size: 17px;
  color: var(--muted);
  max-width: 600px;
  margin: 0 auto;
}

/* ---------- 关于页 ---------- */
.about-split {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}

.about-split h2 {
  font-size: 30px;
  font-weight: 800;
  color: var(--ink);
  margin-bottom: 24px;
}

.about-split p { margin-bottom: 16px; }

.about-photo { position: relative; }

.about-photo::before {
  content: "";
  position: absolute;
  inset: -18px auto auto -18px;
  width: 120px;
  height: 120px;
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(77, 107, 254, 0.16), rgba(124, 92, 255, 0.16));
  z-index: 0;
}

.about-photo img {
  position: relative;
  z-index: 1;
  border-radius: var(--radius);
  box-shadow: 0 24px 48px rgba(11, 21, 48, 0.14);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  max-width: 860px;
  margin: 0 auto;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 24px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: var(--tr);
}

.contact-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.contact-item .card-icon { margin-bottom: 0; flex-shrink: 0; }

.contact-item b {
  display: block;
  font-size: 14px;
  color: var(--ink);
  font-weight: 600;
}

.contact-item span {
  font-size: 14px;
  color: var(--muted);
  word-break: break-all;
}

/* ---------- 法律页 ---------- */
.legal-body {
  max-width: 760px;
  margin: 0 auto;
}

.legal-body h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  margin: 32px 0 12px;
}

.legal-body p, .legal-body li { font-size: 15px; margin-bottom: 10px; }
.legal-body ul { padding-left: 22px; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--footer-bg);
  color: #8a93ad;
  padding: 56px 0 32px;
  text-align: center;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 20px;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 28px;
  flex-wrap: wrap;
  margin-bottom: 28px;
}

.footer-links a {
  color: #8a93ad;
  font-size: 14px;
  transition: var(--tr);
}

.footer-links a:hover { color: #fff; }

.footer-copy {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 24px;
  font-size: 13px;
  line-height: 2;
}

.footer-copy a { color: #8a93ad; }
.footer-copy a:hover { color: #fff; }
.footer-copy .sep { margin: 0 10px; opacity: 0.4; }

/* ---------- 入场动效 ---------- */
@keyframes fade-up {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: translateY(0); }
}

.fade-up { animation: fade-up 0.7s ease both; }
.d1 { animation-delay: 0.08s; }
.d2 { animation-delay: 0.18s; }
.d3 { animation-delay: 0.28s; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .fade-up { animation: none; }
  * { transition: none; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 860px) {
  .hero { padding: 84px 0 72px; }
  .hero-title { font-size: 32px; }
  .page-hero h1 { font-size: 28px; }
  .section { padding: 64px 0; }
  .section-head h2 { font-size: 26px; }
  .cards-3 { grid-template-columns: 1fr; }
  .clients-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-strip { gap: 36px; }
  .about-split { grid-template-columns: 1fr; gap: 40px; }
  .contact-grid { grid-template-columns: 1fr; }

  .nav-toggle { display: inline-flex; }

  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 16px 24px rgba(16, 24, 64, 0.08);
    padding: 8px 24px 16px;
    display: none;
  }

  .nav-links.open { display: flex; }
  .nav-links li { border-top: 1px solid var(--border); }
  .nav-links a { display: block; padding: 12px 0; }
  .nav-links a.active::after { display: none; }
  .nav-cta { justify-content: center; margin: 12px 0 4px; }
}