/* 它虎智能体官网样式：无外部依赖，深色导航 + 浅色正文 */
:root {
  --navy: #0b1f3a;
  --navy-deep: #071527;
  --ink: #1f2937;
  --muted: #5b6573;
  --line: #e5e9f0;
  --bg: #ffffff;
  --bg-soft: #f4f7fb;
  --accent: #f59e0b;
  --accent-deep: #d97706;
  --link: #1d4ed8;
  --radius: 12px;
  --max: 1120px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", "Segoe UI", Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; }
h1, h2, h3, h4 { line-height: 1.3; margin: 0 0 .5em; font-weight: 700; }
h1 { font-size: 2.4rem; }
h2 { font-size: 1.8rem; }
h3 { font-size: 1.2rem; }
p { margin: 0 0 1em; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; background: #fff; padding: 8px; z-index: 100; }

/* 导航 */
.nav { background: var(--navy); color: #fff; position: sticky; top: 0; z-index: 50; box-shadow: 0 1px 0 rgba(255,255,255,.08); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: #fff; font-weight: 700; font-size: 1.05rem; }
.brand img { height: 32px; width: auto; }
.brand:hover { text-decoration: none; }
.nav-toggle { display: none; background: none; border: 1px solid rgba(255,255,255,.35); color: #fff; padding: 6px 10px; border-radius: 6px; font-size: 1rem; }
.menu { display: flex; gap: 4px; list-style: none; margin: 0; padding: 0; }
.menu a { color: rgba(255,255,255,.85); padding: 8px 12px; border-radius: 6px; display: block; }
.menu a:hover, .menu a[aria-current="page"] { color: #fff; background: rgba(255,255,255,.12); text-decoration: none; }
.menu .cta a { background: var(--accent); color: var(--navy-deep); font-weight: 600; margin-left: 8px; }
.menu .cta a:hover { background: var(--accent-deep); color: #fff; }

/* 首屏 */
.hero { background: linear-gradient(160deg, var(--navy-deep) 0%, var(--navy) 55%, #123b6b 100%); color: #fff; padding: 80px 0 72px; }
.hero .eyebrow { color: var(--accent); font-weight: 600; letter-spacing: .08em; text-transform: uppercase; font-size: .85rem; margin-bottom: 12px; }
.hero h1 { color: #fff; max-width: 760px; }
.hero .lead { font-size: 1.15rem; color: rgba(255,255,255,.85); max-width: 680px; }
.hero-sub { padding: 56px 0 40px; }
.hero-sub h1 { font-size: 2rem; }
.hero-sub .lead { font-size: 1.05rem; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.btn { display: inline-block; padding: 12px 22px; border-radius: 8px; font-weight: 600; border: 1px solid transparent; }
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--accent); color: var(--navy-deep); }
.btn-primary:hover { background: var(--accent-deep); color: #fff; }
.btn-ghost { border-color: rgba(255,255,255,.5); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.1); }
.btn-dark { background: var(--navy); color: #fff; }
.btn-dark:hover { background: var(--navy-deep); }

/* 区块 */
.section { padding: 64px 0; }
.section.soft { background: var(--bg-soft); }
.section-head { max-width: 720px; margin-bottom: 36px; }
.section-head .kicker { color: var(--accent-deep); font-weight: 600; font-size: .9rem; letter-spacing: .06em; }
.section-head p { color: var(--muted); }
.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.card h3 { margin-top: 0; }
.card p { color: var(--muted); margin-bottom: 0; }
.card .num { display: inline-block; width: 36px; height: 36px; border-radius: 50%; background: var(--navy); color: var(--accent); font-weight: 700; text-align: center; line-height: 36px; margin-bottom: 14px; }
.card ul { color: var(--muted); padding-left: 1.2em; margin: 8px 0 0; }
.card li { margin-bottom: 6px; }
.stat { text-align: center; padding: 20px; }
.stat strong { display: block; font-size: 2rem; color: var(--navy); }
.stat span { color: var(--muted); }
.steps { counter-reset: step; }
.feature { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; padding: 40px 0; border-top: 1px solid var(--line); }
.feature:first-of-type { border-top: 0; }
.feature h3 { font-size: 1.4rem; }
.feature ul { padding-left: 1.2em; color: var(--ink); }
.feature li { margin-bottom: 8px; }
.feature .visual { background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; font-size: .95rem; }
.feature .visual .chat { background: #fff; border-radius: 8px; padding: 12px 14px; margin-bottom: 10px; border: 1px solid var(--line); }
.feature .visual .chat.q { border-left: 4px solid var(--accent); }
.feature .visual .chat.a { border-left: 4px solid var(--navy); }
.feature .visual .chat small { display: block; color: var(--muted); }
.tag { display: inline-block; background: #eef2ff; color: #3730a3; border-radius: 999px; padding: 2px 10px; font-size: .8rem; margin-right: 6px; }
.table { width: 100%; border-collapse: collapse; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.table th, .table td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
.table th { background: var(--bg-soft); font-weight: 600; }
.table tr:last-child td { border-bottom: 0; }
.note { background: #fffbeb; border: 1px solid #fde68a; border-radius: var(--radius); padding: 16px 20px; color: #78350f; }
.cta-band { background: var(--navy); color: #fff; padding: 56px 0; text-align: center; }
.cta-band h2 { color: #fff; }
.cta-band p { color: rgba(255,255,255,.8); max-width: 640px; margin: 0 auto 20px; }
.contact-list { list-style: none; padding: 0; margin: 0; }
.contact-list li { padding: 14px 0; border-bottom: 1px solid var(--line); display: flex; gap: 16px; }
.contact-list li:last-child { border-bottom: 0; }
.contact-list .k { min-width: 96px; color: var(--muted); }
.contact-list .v { font-weight: 600; font-size: 1.05rem; }

/* 页脚 */
.footer { background: var(--navy-deep); color: rgba(255,255,255,.75); padding: 48px 0 28px; font-size: .95rem; }
.footer a { color: rgba(255,255,255,.85); }
.footer .cols { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 32px; }
.footer h4 { color: #fff; margin-bottom: 12px; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer li { margin-bottom: 8px; }
.footer .legal { border-top: 1px solid rgba(255,255,255,.12); margin-top: 32px; padding-top: 20px; font-size: .85rem; color: rgba(255,255,255,.55); }

@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .feature { grid-template-columns: 1fr; gap: 20px; }
  .footer .cols { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  h1 { font-size: 1.85rem; }
  h2 { font-size: 1.5rem; }
  .hero { padding: 56px 0 48px; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .nav-toggle { display: block; }
  .menu { display: none; position: absolute; left: 0; right: 0; top: 64px; background: var(--navy); flex-direction: column; padding: 8px 12px 16px; }
  .menu.open { display: flex; }
  .menu .cta a { margin-left: 0; margin-top: 6px; }
  .footer .cols { grid-template-columns: 1fr; }
  .table { display: block; overflow-x: auto; }
}