/* =========================================================
   知信链 ZXCHAIN — 主样式
   ========================================================= */
:root {
  --primary: #0d2b52;
  --primary-dark: #081d38;
  --accent: #22d3ee;
  --accent-2: #f5b942;
  --ink: #0f2743;
  --text: #3c4a5e;
  --muted: #6b7a8d;
  --bg: #ffffff;
  --bg-soft: #f4f8fd;
  --line: #e4ecf5;
  --radius: 16px;
  --shadow: 0 20px 50px -20px rgba(13, 43, 82, .25);
  --font: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  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; }
.container { width: min(1180px, 92%); margin-inline: auto; }
.section { padding: 96px 0; }

/* 通用标题 */
.section-head { text-align: center; max-width: 720px; margin: 0 auto 60px; }
.kicker {
  font-size: .82rem; letter-spacing: .22em; text-transform: uppercase;
  color: var(--accent); font-weight: 700; margin-bottom: 12px;
}
.section-head h2 { font-size: clamp(1.7rem, 3.4vw, 2.5rem); color: var(--ink); font-weight: 900; line-height: 1.3; }
.section-head .sub { margin-top: 16px; color: var(--muted); font-size: 1.02rem; }
.section-dark .section-head h2,
.section-dark .section-head .sub { color: #fff; }
.section-dark .section-head .sub { color: rgba(255,255,255,.72); }
.section-dark { background: linear-gradient(135deg, #0a1f3d 0%, #0d2b52 60%, #0f3564 100%); position: relative; overflow: hidden; }
.section-dark::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: .5;
  background-image: radial-gradient(rgba(34,211,238,.14) 1px, transparent 1px);
  background-size: 34px 34px;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: .85rem 1.7rem; border-radius: 999px; font-weight: 700; font-size: 1rem;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
  border: 2px solid transparent; cursor: pointer; white-space: nowrap;
}
.btn-primary { background: linear-gradient(135deg, var(--accent) 0%, #0ea5c9 100%); color: #06213a; box-shadow: 0 12px 28px -12px rgba(34,211,238,.7); }
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 18px 34px -12px rgba(34,211,238,.85); }
.btn-ghost { color: #fff; border-color: rgba(255,255,255,.4); backdrop-filter: blur(4px); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-3px); }
.btn-light { background: #fff; color: var(--primary); }
.btn-light:hover { transform: translateY(-3px); box-shadow: 0 18px 34px -14px rgba(255,255,255,.4); }
.btn .arrow { transition: transform .2s; }
.btn:hover .arrow { transform: translateX(4px); }

/* ===== 导航 ===== */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  transition: background .3s ease, box-shadow .3s ease, backdrop-filter .3s ease;
  padding: 14px 0;
}
.site-header.scrolled { background: rgba(255,255,255,.86); backdrop-filter: blur(14px); box-shadow: 0 6px 24px -18px rgba(13,43,82,.35); }
.header-inner { display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 10px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text strong { font-size: 1.28rem; color: #fff; font-weight: 900; letter-spacing: .04em; transition: color .3s; }
.brand-text em { font-style: normal; font-size: .62rem; letter-spacing: .34em; color: var(--accent); }
.main-nav { display: flex; align-items: center; gap: 6px; }
.main-nav a {
  color: rgba(255,255,255,.85); padding: 8px 14px; border-radius: 999px;
  font-size: .97rem; transition: color .2s, background .2s;
}
.main-nav a:hover { color: var(--accent); }
.main-nav a.active { color: var(--accent); }
.main-nav .nav-cta {
  margin-left: 10px; color: #fff; background: linear-gradient(135deg, var(--accent), #0ea5c9);
  font-weight: 700; padding: 9px 20px; border: none; color: #06213a;
}
.site-header.scrolled .brand-text strong { color: var(--ink); }
.site-header.scrolled .main-nav a { color: var(--text); }
.site-header.scrolled .main-nav a:hover,
.site-header.scrolled .main-nav a.active { color: var(--accent); }
.site-header.scrolled .main-nav .nav-cta { color: #06213a; }

.nav-toggle {
  display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px;
}
.nav-toggle span { width: 24px; height: 2.5px; background: #fff; border-radius: 2px; transition: .3s; }
.site-header.scrolled .nav-toggle span { background: var(--ink); }

/* ===== Hero ===== */
.hero {
  position: relative; color: #fff; padding: 160px 0 60px;
  background: radial-gradient(1200px 700px at 85% -10%, #15447d 0%, transparent 55%),
              linear-gradient(160deg, #081d38 0%, #0d2b52 55%, #0f3564 100%);
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0; opacity: .4; pointer-events: none;
  background-image:
    radial-gradient(rgba(34,211,238,.18) 1.5px, transparent 1.5px),
    radial-gradient(rgba(245,185,66,.16) 1.5px, transparent 1.5px);
  background-size: 46px 46px, 70px 70px;
  background-position: 0 0, 23px 23px;
  mask-image: radial-gradient(ellipse at 60% 40%, #000 30%, transparent 78%);
}
.hero-inner {
  display: grid; grid-template-columns: 1.05fr .95fr; gap: 40px; align-items: center; position: relative;
}
.hero-kicker {
  display: inline-block; padding: 7px 16px; border-radius: 999px; font-size: .92rem;
  border: 1px solid rgba(34,211,238,.45); background: rgba(34,211,238,.1); color: var(--accent);
  margin-bottom: 22px;
}
.hero h1 { font-size: clamp(2rem, 4.6vw, 3.4rem); font-weight: 900; line-height: 1.24; letter-spacing: .01em; }
.grad-text {
  background: linear-gradient(92deg, #22d3ee, #5eead4 45%, #f5b942);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; color: transparent;
}
.hero-desc { margin-top: 20px; font-size: 1.08rem; color: rgba(255,255,255,.82); max-width: 540px; }
.hero-desc em { color: var(--accent-2); font-style: normal; font-weight: 600; }
.hero-actions { display: flex; gap: 16px; margin-top: 30px; flex-wrap: wrap; }
.hero-trust { display: flex; gap: 20px; margin-top: 26px; flex-wrap: wrap; font-size: .95rem; color: rgba(255,255,255,.78); }
.hero-trust li { display: flex; align-items: center; gap: 6px; }

/* Hero 视觉 */
.hero-visual { position: relative; min-height: 420px; }
.chain-card {
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius); backdrop-filter: blur(10px); box-shadow: var(--shadow);
}
.card-main { padding: 22px; max-width: 340px; margin-left: auto; }
.chain-card-head { display: flex; align-items: center; gap: 8px; font-size: .82rem; color: rgba(255,255,255,.8); }
.chain-card-head .dot { width: 8px; height: 8px; border-radius: 50%; background: #34d399; box-shadow: 0 0 10px #34d399; }
.chain-card-head .status { margin-left: auto; color: #34d399; font-weight: 700; }
.chain-id { margin-top: 16px; background: rgba(8,29,56,.7); border-radius: 10px; padding: 10px 14px; }
.chain-id small { display: block; font-size: .7rem; color: rgba(255,255,255,.5); letter-spacing: .1em; }
.chain-id code { color: var(--accent); font-size: 1rem; }
.chain-value { margin-top: 16px; display: flex; align-items: baseline; gap: 10px; }
.chain-value strong { font-size: 2rem; font-weight: 900; color: #fff; letter-spacing: .02em; }
.chain-value span { color: rgba(255,255,255,.6); font-size: .85rem; }
.chain-tags { display: flex; gap: 8px; margin-top: 14px; flex-wrap: wrap; }
.tag { padding: 4px 12px; border-radius: 999px; font-size: .78rem; border: 1px solid rgba(34,211,238,.4); color: #a5f3fc; background: rgba(34,211,238,.08); }
.card-float-left, .card-float-right {
  position: absolute; display: flex; align-items: center; gap: 12px; padding: 14px 18px; max-width: 230px;
}
.card-float-left { bottom: 20px; left: 0; animation: float 5s ease-in-out infinite; }
.card-float-right { top: 30px; left: -10px; animation: float 6s ease-in-out .8s infinite; }
.card-float-left strong, .card-float-right strong { color: #fff; font-size: .98rem; display: block; }
.card-float-left small, .card-float-right small { color: rgba(255,255,255,.6); font-size: .74rem; }
.mini-ico { font-size: 1.6rem; }
@keyframes float { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-12px); } }

/* 统计 */
.stats {
  position: relative; margin-top: 70px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
  background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.12);
  border-radius: 20px; padding: 30px 24px; backdrop-filter: blur(8px);
}
.stat { text-align: center; }
.stat strong { display: block; font-size: clamp(1.7rem, 3vw, 2.4rem); font-weight: 900; color: #fff; line-height: 1.2; }
.stat strong::after { content: attr(data-suffix); color: var(--accent); }
.stat span { color: rgba(255,255,255,.62); font-size: .9rem; }

/* ===== 服务卡片 ===== */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 26px; transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease;
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-8px); box-shadow: var(--shadow); border-color: rgba(34,211,238,.4); }
.card-ico {
  width: 60px; height: 60px; border-radius: 16px; display: grid; place-items: center;
  margin-bottom: 20px; color: #fff;
}
.ico-blue { background: linear-gradient(135deg,#3b82f6,#1d4ed8); box-shadow: 0 10px 20px -10px rgba(59,130,246,.7); }
.ico-gold { background: linear-gradient(135deg,#f5b942,#d97706); box-shadow: 0 10px 20px -10px rgba(245,185,66,.7); }
.ico-green { background: linear-gradient(135deg,#34d399,#059669); box-shadow: 0 10px 20px -10px rgba(52,211,153,.7); }
.ico-purple { background: linear-gradient(135deg,#a78bfa,#7c3aed); box-shadow: 0 10px 20px -10px rgba(167,139,250,.7); }
.ico-red { background: linear-gradient(135deg,#fb7185,#e11d48); box-shadow: 0 10px 20px -10px rgba(251,113,133,.7); }
.ico-cyan { background: linear-gradient(135deg,#22d3ee,#0891b2); box-shadow: 0 10px 20px -10px rgba(34,211,238,.7); }
.card h3 { color: var(--ink); font-size: 1.25rem; margin-bottom: 10px; }
.card > p { color: var(--muted); font-size: .95rem; }
.card ul { margin-top: 16px; display: grid; gap: 7px; }
.card ul li { position: relative; padding-left: 22px; color: var(--text); font-size: .92rem; }
.card ul li::before { content: "✓"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }
.card-link { margin-top: auto; padding-top: 20px; color: var(--primary); font-weight: 700; font-size: .95rem; }
.card-link:hover { color: var(--accent); }

/* ===== 步骤 ===== */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; position: relative; }
.step {
  background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.12);
  border-radius: var(--radius); padding: 34px 28px; position: relative; transition: transform .28s, background .28s;
}
.step:hover { transform: translateY(-6px); background: rgba(255,255,255,.09); }
.step-num {
  position: absolute; top: 16px; right: 22px; font-size: 3rem; font-weight: 900;
  color: rgba(255,255,255,.08); letter-spacing: .02em;
}
.step-ico { font-size: 2rem; display: inline-block; }
.step h3 { color: #fff; font-size: 1.28rem; margin: 14px 0 8px; }
.step h3::before { content: ""; display: block; width: 34px; height: 3px; border-radius: 3px; background: var(--accent); margin-bottom: 10px; }
.step p { color: rgba(255,255,255,.72); font-size: .95rem; }
.steps-cta { text-align: center; margin-top: 44px; }

/* ===== 优势 ===== */
.advantage-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.advantage {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px 24px; display: flex; flex-direction: column; gap: 6px;
  transition: transform .28s, box-shadow .28s, border-color .28s;
}
.advantage:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: rgba(245,185,66,.45); }
.a-ico { font-size: 2rem; }
.advantage h3 { color: var(--ink); font-size: 1.15rem; margin-top: 8px; }
.advantage p { color: var(--muted); font-size: .93rem; }

/* ===== 关于 ===== */
.section-about { background: var(--bg-soft); }
.about-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: center; }
.about-copy h2 { font-size: clamp(1.7rem, 3.2vw, 2.4rem); color: var(--ink); font-weight: 900; margin-bottom: 18px; }
.about-copy p { color: var(--text); margin-bottom: 14px; }
.about-copy p em { color: var(--accent); font-style: normal; font-weight: 700; }
.about-copy p strong { color: var(--primary); }
.about-points { margin-top: 16px; display: grid; gap: 10px; }
.about-points li {
  background: #fff; border: 1px solid var(--line); border-left: 4px solid var(--accent);
  padding: 12px 16px; border-radius: 10px; color: var(--text); font-size: .95rem;
}
.about-points b { color: var(--ink); }
.about-panel {
  background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 34px 30px;
  box-shadow: var(--shadow);
}
.panel-item { margin-bottom: 26px; }
.panel-item:last-child { margin-bottom: 0; }
.panel-item > span { display: flex; justify-content: space-between; color: var(--ink); font-weight: 600; font-size: .95rem; margin-bottom: 8px; }
.bar { height: 10px; border-radius: 999px; background: #edf2f9; overflow: hidden; }
.bar i { display: block; height: 100%; width: 0; border-radius: 999px; background: linear-gradient(90deg, var(--accent), #0ea5c9); transition: width 1.2s ease; }
.panel-item em { font-style: normal; display: inline-block; margin-top: 8px; font-weight: 800; color: var(--primary); font-size: .9rem; }

/* ===== CTA ===== */
.section-cta { background: linear-gradient(150deg, #081d38, #0d2b52 55%, #103a6b); position: relative; overflow: hidden; }
.section-cta::before { content: ""; position: absolute; inset: 0; background: radial-gradient(rgba(34,211,238,.15) 1px, transparent 1px); background-size: 30px 30px; opacity: .5; }
.cta-box {
  position: relative; text-align: center; max-width: 760px; margin: 0 auto; color: #fff;
}
.cta-box h2 { font-size: clamp(1.6rem, 3.2vw, 2.3rem); font-weight: 900; }
.cta-box > p { color: rgba(255,255,255,.78); margin-top: 14px; }
.cta-box > p strong { color: var(--accent-2); font-weight: 700; }
.email-banner {
  margin: 34px auto 0; max-width: 600px; display: flex; align-items: center; gap: 18px;
  background: rgba(255,255,255,.07); border: 1px solid rgba(34,211,238,.5); border-radius: 22px;
  padding: 20px 24px; text-align: left; color: #fff;
  box-shadow: 0 18px 44px -26px rgba(0,0,0,.7); transition: transform .25s ease, background .25s ease, border-color .25s ease, box-shadow .25s ease;
}
.email-banner:hover {
  transform: translateY(-4px); background: rgba(255,255,255,.11); border-color: var(--accent);
  box-shadow: 0 24px 48px -22px rgba(34,211,238,.5);
}
.email-ico {
  flex: 0 0 auto; width: 58px; height: 58px; border-radius: 16px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--accent), #0ea5c9); color: #06213a;
  box-shadow: 0 10px 22px -10px rgba(34,211,238,.8);
}
.email-main { min-width: 0; display: flex; flex-direction: column; line-height: 1.35; }
.email-main small { font-size: .84rem; color: rgba(255,255,255,.62); letter-spacing: .06em; }
.email-main strong { font-size: clamp(1.3rem, 3vw, 1.9rem); font-weight: 900; letter-spacing: .02em; color: #fff; transition: color .2s; word-break: break-all; }
.email-banner:hover .email-main strong { color: var(--accent); }
.email-arrow {
  margin-left: auto; flex: 0 0 auto; font-weight: 700; font-size: .85rem; color: var(--accent); white-space: nowrap;
  border: 1px solid rgba(34,211,238,.5); padding: 8px 14px; border-radius: 999px; transition: background .2s, color .2s;
}
.email-banner:hover .email-arrow { background: var(--accent); color: #06213a; }
.btn-copy {
  margin-top: 24px; background: transparent; color: rgba(255,255,255,.85);
  border: 1px solid rgba(255,255,255,.35); font-size: .92rem; padding: .55rem 1.3rem;
}
.btn-copy:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }
.copy-tip { min-height: 1.5em; margin-top: 12px; font-size: .92rem; }
.copy-tip.ok { color: #6ee7b7; }
.copy-tip.err { color: #fda4af; }
.cta-meta { margin-top: 10px; display: flex; gap: 26px; justify-content: center; flex-wrap: wrap; color: rgba(255,255,255,.66); font-size: .92rem; }
@media (max-width: 560px) {
  .email-banner { flex-direction: column; align-items: center; text-align: center; gap: 14px; }
  .email-arrow { margin-left: 0; }
}

/* ===== 页脚 ===== */
.site-footer { background: #071a30; color: rgba(255,255,255,.72); padding: 64px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 36px; padding-bottom: 48px; }
.footer-brand p { margin-top: 16px; max-width: 320px; color: rgba(255,255,255,.6); font-size: .92rem; }
.brand-light .brand-text strong { color: #fff; }
.footer-col h4 { color: #fff; margin-bottom: 16px; font-size: 1rem; }
.footer-col a { display: block; color: rgba(255,255,255,.6); font-size: .93rem; padding: 5px 0; transition: color .2s, transform .2s; }
.footer-col a:hover { color: var(--accent); transform: translateX(4px); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); padding: 22px 0; }
.footer-bottom .container { display: flex; justify-content: space-between; gap: 10px; flex-wrap: wrap; }
.footer-bottom p { font-size: .85rem; color: rgba(255,255,255,.45); }

/* ===== 入场动画 ===== */
.reveal { opacity: 0; transform: translateY(34px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ===== 响应式 ===== */
@media (max-width: 992px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-visual { order: -1; max-width: 480px; margin-inline: auto; }
  .cards { grid-template-columns: repeat(2, 1fr); }
  .advantage-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .section { padding: 68px 0; }
  .main-nav {
    position: fixed; inset: 0 0 0 auto; width: min(78vw, 300px); flex-direction: column;
    background: var(--primary-dark); padding: 90px 26px 30px; gap: 8px; align-items: stretch;
    transform: translateX(100%); transition: transform .32s ease; box-shadow: -20px 0 50px rgba(0,0,0,.3);
  }
  .main-nav.open { transform: none; }
  .main-nav a { padding: 13px 14px; font-size: 1.05rem; color: #fff; }
  .main-nav .nav-cta { text-align: center; margin: 14px 0 0; }
  .nav-toggle { display: flex; z-index: 120; }
  .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); }
  .nav-toggle.open span { background: #fff; }
  body.nav-locked { overflow: hidden; }
  .hero { padding: 120px 0 50px; }
  .steps, .cards, .advantage-grid { grid-template-columns: 1fr; }
  .footer-bottom .container { flex-direction: column; text-align: center; }
  .hero-actions .btn { flex: 1 1 auto; }
}