/* ============================================================
   DataSeek 公司官网 — 全局样式
   ============================================================ */
:root {
  --navy: #0a1f44;
  --navy-2: #123a7a;
  --blue: #1565c0;
  --sky: #4fc3f7;
  --ink: #2c3e50;
  --gray: #56718a;
  --line: #e2e9f2;
  --bg-soft: #f5f8fc;
  --orange: #e07b39;
  --green: #2e9e5b;
  --radius: 12px;
  --shadow: 0 6px 24px rgba(16, 42, 90, 0.10);
  --shadow-lg: 0 16px 48px rgba(16, 42, 90, 0.16);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", sans-serif;
  color: var(--ink);
  background: #fff;
  line-height: 1.7;
}

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

.container { max-width: 1180px; margin: 0 auto; padding: 0 24px; }

/* ============ 顶部导航 ============ */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10, 31, 68, 0.92);
  backdrop-filter: blur(10px);
  transition: background .3s, box-shadow .3s;
}
.site-header.scrolled { background: rgba(10, 31, 68, 0.98); box-shadow: 0 2px 16px rgba(0,0,0,.25); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { font-size: 24px; font-weight: 700; color: #fff; letter-spacing: 1px; }
.brand span { color: var(--sky); }
.nav-links { display: flex; align-items: center; gap: 6px; }
.nav-links a {
  color: #cfe3f7; font-size: 15px; padding: 8px 16px; border-radius: 8px;
  transition: color .2s, background .2s;
}
.nav-links a:hover { color: #fff; background: rgba(255,255,255,.08); }
.nav-links a.active { color: #fff; background: rgba(79,195,247,.18); }
.nav-links a.nav-cta {
  background: var(--blue); color: #fff; margin-left: 10px; padding: 9px 22px;
}
.nav-links a.nav-cta:hover { background: #1976d2; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 24px; height: 2px; background: #fff; margin: 5px 0; border-radius: 2px; transition: .3s; }

/* ============ Hero ============ */
.hero {
  background: linear-gradient(135deg, #0a1f44 0%, #123a7a 55%, #1565c0 100%);
  color: #fff; padding: 160px 0 96px; position: relative; overflow: hidden;
}
.hero::before {
  content: ""; position: absolute; right: -140px; top: -140px; width: 520px; height: 520px;
  border-radius: 50%; background: radial-gradient(circle, rgba(79,195,247,.22), transparent 65%);
}
.hero::after {
  content: ""; position: absolute; left: -100px; bottom: -180px; width: 420px; height: 420px;
  border-radius: 50%; background: radial-gradient(circle, rgba(21,101,192,.35), transparent 65%);
}
.hero .container { position: relative; z-index: 1; }
.hero-kicker {
  display: inline-block; border: 1px solid rgba(255,255,255,.4); color: #dcecfb;
  font-size: 13px; padding: 5px 16px; border-radius: 20px; margin-bottom: 24px; letter-spacing: 1px;
}
.hero h1 { font-size: 44px; line-height: 1.35; font-weight: 700; max-width: 760px; }
.hero h1 em { font-style: normal; color: var(--sky); }
.hero .sub { font-size: 18px; color: #b3d4f5; margin-top: 18px; max-width: 680px; line-height: 1.9; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; }
.hero-tags .tag {
  border: 1px solid rgba(255,255,255,.45); border-radius: 20px; padding: 6px 16px;
  font-size: 13px; color: #dcecfb;
}
.hero-actions { margin-top: 40px; display: flex; gap: 16px; flex-wrap: wrap; }

.btn {
  display: inline-block; padding: 13px 32px; border-radius: 8px; font-size: 16px;
  font-weight: 600; transition: transform .2s, box-shadow .2s, background .2s; cursor: pointer; border: none;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--sky); color: var(--navy); box-shadow: 0 6px 20px rgba(79,195,247,.35); }
.btn-primary:hover { background: #6fd0f9; }
.btn-ghost { border: 1px solid rgba(255,255,255,.55); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.1); }
.btn-blue { background: var(--blue); color: #fff; box-shadow: 0 6px 20px rgba(21,101,192,.3); }
.btn-blue:hover { background: #1976d2; }

/* Hero 平台截图 */
.hero-shot { margin-top: 56px; }
.hero-shot .frame {
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-lg);
  border: 1px solid rgba(255,255,255,.18); max-width: 920px; margin: 0 auto;
}

/* ============ 数字带 ============ */
.stats-band { background: var(--navy); color: #fff; padding: 36px 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; text-align: center; }
.stat .num { font-size: 34px; font-weight: 800; color: var(--sky); }
.stat .num small { font-size: 18px; font-weight: 600; }
.stat .label { font-size: 14px; color: #9db8d8; margin-top: 4px; }

/* ============ 通用 Section ============ */
.section { padding: 88px 0; }
.section.soft { background: var(--bg-soft); }
.section-head { text-align: center; max-width: 760px; margin: 0 auto 52px; }
.section-head .kicker {
  display: inline-block; background: #eef4fb; color: var(--blue); border: 1px solid #cfe0f5;
  font-size: 13px; font-weight: 700; padding: 4px 16px; border-radius: 14px; letter-spacing: 2px;
}
.section-head h2 { font-size: 32px; color: var(--navy); margin-top: 16px; }
.section-head p { font-size: 16px; color: var(--gray); margin-top: 12px; }

/* ============ 卡片 ============ */
.cards { display: grid; gap: 24px; }
.cards.c2 { grid-template-columns: repeat(2, 1fr); }
.cards.c3 { grid-template-columns: repeat(3, 1fr); }
.cards.c4 { grid-template-columns: repeat(4, 1fr); }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 28px; transition: transform .25s, box-shadow .25s;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.card .ico {
  width: 48px; height: 48px; border-radius: 12px; background: #eef4fb; color: var(--blue);
  display: flex; align-items: center; justify-content: center; font-size: 24px; margin-bottom: 18px;
}
.card h3 { font-size: 18px; color: var(--navy); margin-bottom: 10px; }
.card p { font-size: 14px; color: var(--gray); line-height: 1.8; }

/* 痛点卡片 */
.card.pain { border-left: 4px solid var(--orange); background: #fdf9f5; }
.card.pain h3 { color: #a04b12; }

/* ============ 流程 ============ */
.flow { display: flex; align-items: stretch; gap: 12px; margin-top: 12px; }
.flow .step {
  flex: 1; background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 16px; text-align: center; transition: transform .25s, box-shadow .25s;
}
.flow .step:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.flow .step .no {
  width: 34px; height: 34px; margin: 0 auto 12px; border-radius: 50%;
  background: var(--blue); color: #fff; font-weight: 700; font-size: 15px;
  display: flex; align-items: center; justify-content: center;
}
.flow .step b { display: block; font-size: 16px; color: var(--navy); margin-bottom: 6px; }
.flow .step span { font-size: 12.5px; color: var(--gray); line-height: 1.6; display: block; }
.flow .arr { align-self: center; color: var(--blue); font-size: 22px; font-weight: 700; }

/* ============ 图文交替 Feature ============ */
.feature { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; padding: 44px 0; }
.feature .shot {
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow);
  border: 1px solid var(--line); background: #fff;
}
.feature .txt .scene-no {
  display: inline-block; background: #eef4fb; color: var(--blue); border: 1px solid #cfe0f5;
  font-size: 12px; font-weight: 700; padding: 3px 14px; border-radius: 12px; margin-bottom: 14px;
}
.feature .txt h3 { font-size: 26px; color: var(--navy); margin-bottom: 14px; }
.feature .txt > p { font-size: 15px; color: var(--gray); margin-bottom: 16px; }
.feature .txt ul li {
  font-size: 14px; color: #445; padding: 6px 0 6px 26px; position: relative; line-height: 1.7;
}
.feature .txt ul li::before {
  content: "✓"; position: absolute; left: 0; top: 6px; color: var(--green); font-weight: 700;
}
.feature .txt ul li b { color: var(--navy); }
.feature.rev .shot { order: 2; }
.feature.rev .txt { order: 1; }

/* ============ 场景网格 ============ */
.scene-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.scene {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 22px; transition: transform .25s, box-shadow .25s, border-color .25s;
}
.scene:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: #bcd4ee; }
.scene .no { font-size: 13px; font-weight: 800; color: var(--sky); letter-spacing: 1px; }
.scene h4 { font-size: 16px; color: var(--navy); margin: 6px 0 8px; }
.scene p { font-size: 13px; color: var(--gray); line-height: 1.75; }

/* ============ 对比表 ============ */
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.compare-table th { background: var(--navy); color: #fff; padding: 16px 20px; text-align: left; font-size: 15px; }
.compare-table td { border-bottom: 1px solid var(--line); padding: 14px 20px; font-size: 14px; color: #445; }
.compare-table tr:last-child td { border-bottom: none; }
.compare-table td.arr { text-align: center; color: var(--blue); font-weight: 700; width: 60px; }
.compare-table tr:nth-child(even) td { background: #f7fafd; }

/* ============ 价值 ============ */
.value-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.value {
  background: #fff; border: 1px solid var(--line); border-top: 4px solid var(--blue);
  border-radius: var(--radius); padding: 30px 26px; transition: transform .25s, box-shadow .25s;
}
.value:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.value .word { font-size: 26px; font-weight: 800; color: var(--blue); }
.value p { font-size: 14px; color: var(--gray); margin-top: 12px; line-height: 1.85; }
.value p b { color: var(--navy); }

/* ============ CTA 大横幅 ============ */
.cta-band {
  background: linear-gradient(135deg, #0a1f44 0%, #14407e 60%, #1565c0 100%);
  color: #fff; text-align: center; padding: 80px 24px; position: relative; overflow: hidden;
}
.cta-band::before {
  content: ""; position: absolute; left: 50%; top: -220px; transform: translateX(-50%);
  width: 640px; height: 640px; border-radius: 50%;
  background: radial-gradient(circle, rgba(79,195,247,.16), transparent 65%);
}
.cta-band h2 { font-size: 32px; position: relative; }
.cta-band p { color: #b3d4f5; font-size: 16px; margin-top: 14px; position: relative; }
.cta-band .btn { margin-top: 32px; position: relative; }

/* ============ 页脚 ============ */
.site-footer { background: var(--navy); color: #9db8d8; padding: 60px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.4fr; gap: 40px; padding-bottom: 44px; }
.footer-grid .brand { margin-bottom: 14px; display: inline-block; }
.footer-grid .about { font-size: 13.5px; line-height: 1.9; max-width: 340px; }
.footer-grid h5 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.footer-grid li { margin-bottom: 10px; }
.footer-grid li a { font-size: 13.5px; transition: color .2s; }
.footer-grid li a:hover { color: var(--sky); }
.footer-grid .contact li { font-size: 13.5px; display: flex; gap: 8px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1); padding: 20px 0; text-align: center;
  font-size: 12.5px; color: #6f8db0;
}
.footer-bottom a { color: inherit; text-decoration: none; transition: color .2s; }
.footer-bottom a:hover { color: var(--sky); }

/* ============ 内页 Banner ============ */
.page-banner {
  background: linear-gradient(135deg, #0a1f44 0%, #123a7a 55%, #1565c0 100%);
  color: #fff; padding: 148px 0 72px; text-align: center;
}
.page-banner h1 { font-size: 38px; }
.page-banner p { color: #b3d4f5; font-size: 16px; margin-top: 14px; max-width: 680px; margin-left: auto; margin-right: auto; }

/* ============ 时间线（关于我们） ============ */
.timeline { max-width: 720px; margin: 0 auto; position: relative; padding-left: 32px; }
.timeline::before { content: ""; position: absolute; left: 8px; top: 6px; bottom: 6px; width: 2px; background: #cfe0f5; }
.timeline .item { position: relative; padding-bottom: 36px; }
.timeline .item:last-child { padding-bottom: 0; }
.timeline .item::before {
  content: ""; position: absolute; left: -30px; top: 6px; width: 14px; height: 14px;
  border-radius: 50%; background: var(--blue); border: 3px solid #dcecfb;
}
.timeline .item h4 { font-size: 17px; color: var(--navy); }
.timeline .item p { font-size: 14px; color: var(--gray); margin-top: 6px; }

/* ============ 滚动入场动画 ============ */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ============ 响应式 ============ */
@media (max-width: 960px) {
  .cards.c3, .cards.c4, .scene-grid, .value-grid, .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .feature, .feature.rev { grid-template-columns: 1fr; gap: 28px; }
  .feature.rev .shot { order: 1; }
  .feature.rev .txt { order: 2; }
  .flow { flex-direction: column; }
  .flow .arr { transform: rotate(90deg); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 34px; }
}
@media (max-width: 640px) {
  .nav-links {
    position: fixed; top: 68px; left: 0; right: 0; flex-direction: column; align-items: stretch;
    background: var(--navy); padding: 12px 20px 20px; gap: 4px;
    transform: translateY(-130%); transition: transform .3s; z-index: 99;
  }
  .nav-links.open { transform: none; }
  .nav-links a.nav-cta { margin-left: 0; text-align: center; }
  .nav-toggle { display: block; }
  .cards.c2, .cards.c3, .cards.c4, .scene-grid, .value-grid, .stats-grid { grid-template-columns: 1fr; }
  .hero { padding: 130px 0 64px; }
  .hero h1 { font-size: 28px; }
  .section { padding: 60px 0; }
  .section-head h2 { font-size: 26px; }
  .footer-grid { grid-template-columns: 1fr; }
}