/* ============================================================
   U慧互联官方网站 - 公共样式
   设计语言：深色科技 SaaS（参考 lynkdo 风格，品牌蓝色调）
   ============================================================ */
:root {
  --bg-deep: #04060d;
  --bg: #070b14;
  --bg-soft: #0b1120;
  --card: rgba(148, 163, 184, 0.06);
  --card-hover: rgba(148, 163, 184, 0.1);
  --border: rgba(148, 163, 184, 0.14);
  --border-strong: rgba(148, 163, 184, 0.25);
  --grad-a: #2f6bff;
  --grad-b: #00d4ff;
  --grad: linear-gradient(135deg, #2f6bff 0%, #00d4ff 100%);
  --grad-soft: linear-gradient(135deg, rgba(47,107,255,.12), rgba(0,212,255,.12));
  --text-1: #f1f5fb;
  --text-2: #94a3b8;
  --text-3: #64748b;
  --ok: #34d399;
  --radius-btn: 12px;
  --radius-card: 20px;
  --nav-h: 68px;
  --container: 1180px;
  --font: "Inter", "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-1);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, textarea, select { font-family: inherit; }

/* ---------------- 动画背景（光晕 + 上升粒子） ---------------- */
.bg-fx { position: fixed; inset: 0; z-index: -1; pointer-events: none; overflow: hidden; background:
  radial-gradient(1200px 600px at 85% -10%, rgba(47,107,255,.16), transparent 60%),
  radial-gradient(900px 500px at -10% 20%, rgba(0,212,255,.1), transparent 55%),
  radial-gradient(1000px 700px at 50% 120%, rgba(47,107,255,.1), transparent 60%),
  var(--bg-deep);
}
.bg-fx .glow {
  position: absolute; border-radius: 50%; filter: blur(90px); opacity: .5;
  animation: breathe 9s ease-in-out infinite;
}
.bg-fx .glow.g1 { width: 420px; height: 420px; right: -120px; top: -80px; background: rgba(47,107,255,.28); }
.bg-fx .glow.g2 { width: 360px; height: 360px; left: -140px; top: 32%; background: rgba(0,212,255,.18); animation-delay: -4s; }
@keyframes breathe { 0%,100% { transform: translate3d(0,0,0) scale(1); opacity: .45; } 50% { transform: translate3d(0,26px,0) scale(1.08); opacity: .7; } }

.bg-fx .particles { position: absolute; inset: 0; }
.bg-fx .p {
  position: absolute; bottom: -12px; border-radius: 50%;
  background: radial-gradient(circle, rgba(120,190,255,.9), rgba(47,107,255,.25));
  animation: rise linear infinite;
}
@keyframes rise {
  0%   { transform: translateY(0) translateX(0); opacity: 0; }
  8%   { opacity: .8; }
  90%  { opacity: .15; }
  100% { transform: translateY(-108vh) translateX(24px); opacity: 0; }
}

/* ---------------- 布局 ---------------- */
.container { width: min(var(--container), 92%); margin: 0 auto; }
.section { padding: 90px 0; position: relative; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 56px; }
.section-head h2 { font-size: clamp(28px, 4vw, 40px); font-weight: 800; letter-spacing: -0.5px; margin-bottom: 14px; }
.section-head p { color: var(--text-2); font-size: 16px; }

/* ---------------- 徽章 / 标题 ---------------- */
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 18px; border-radius: 999px;
  background: rgba(47,107,255,.1);
  border: 1px solid rgba(47,107,255,.28);
  color: #9ec3ff; font-size: 13.5px; font-weight: 500;
  box-shadow: 0 0 24px rgba(47,107,255,.14) inset, 0 0 18px rgba(47,107,255,.1);
}
.badge::before { content: "✦"; color: var(--grad-b); font-size: 12px; }

.grad-text {
  background: var(--grad);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 28px; border-radius: var(--radius-btn);
  font-size: 15px; font-weight: 600; letter-spacing: .3px;
  transition: all .25s ease; white-space: nowrap;
}
.btn-primary {
  background: var(--grad); color: #fff;
  box-shadow: 0 8px 24px rgba(47,107,255,.32);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(47,107,255,.45); }
.btn-ghost {
  background: rgba(148,163,184,.08); color: var(--text-1);
  border: 1px solid var(--border-strong);
}
.btn-ghost:hover { background: rgba(148,163,184,.14); transform: translateY(-2px); }
.btn-sm { padding: 9px 18px; font-size: 13.5px; border-radius: 10px; }

/* ---------------- 顶部公告条 ---------------- */
.announce {
  background: linear-gradient(90deg, rgba(47,107,255,.22), rgba(0,212,255,.22));
  border-bottom: 1px solid rgba(47,107,255,.25);
  text-align: center; font-size: 13.5px; padding: 9px 16px; color: #cfe4ff;
  position: relative; z-index: 60;
}
.announce a { text-decoration: underline; text-underline-offset: 3px; }

/* ---------------- 导航 ---------------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(7, 11, 20, .72);
  backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: var(--nav-h); }
.brand { display: flex; align-items: center; gap: 11px; font-weight: 800; font-size: 19px; letter-spacing: -.3px; }
.brand .logo {
  width: 38px; height: 38px; border-radius: 11px; position: relative;
  background: linear-gradient(135deg, #1b3a7a, #2f6bff);
  box-shadow: 0 4px 16px rgba(47,107,255,.4), inset 0 1px 0 rgba(255,255,255,.25);
  display: flex; align-items: center; justify-content: center;
  font-size: 17px; color: #eaf4ff; font-weight: 900;
}
.brand .logo::after {
  content: ""; position: absolute; right: 3px; bottom: 3px;
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--grad-b); box-shadow: 0 0 8px var(--grad-b);
}
.brand .logo-img {
  width: auto; max-width: 160px; height: 38px; object-fit: contain;
  background: none; box-shadow: none; border-radius: 8px; display: block;
}
.nav-links { display: flex; gap: 6px; align-items: center; }
.nav-links a {
  padding: 9px 16px; border-radius: 10px; font-size: 16.5px; font-weight: 600; color: var(--text-2);
  transition: all .2s;
}
.nav-links a:hover { color: var(--text-1); background: rgba(148,163,184,.09); }
.nav-links a.active { color: #cfe4ff; background: rgba(47,107,255,.14); }
.nav-cta { display: flex; gap: 12px; align-items: center; }
.nav-toggle { display: none; }

/* ---------------- 页脚 ---------------- */
.footer { border-top: 1px solid var(--border); background: rgba(4,6,13,.7); margin-top: 60px; }
.footer-grid {
  display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 48px;
  padding: 64px 0 44px;
}
.footer-brand .brand { margin-bottom: 16px; }
.footer-brand .slogan { color: var(--text-2); font-size: 14px; max-width: 420px; }
.footer h4 { font-size: 15px; margin-bottom: 18px; color: var(--text-1); }
.footer ul { list-style: none; }
.footer ul li { margin-bottom: 11px; }
.footer ul a, .footer .contact-line { color: var(--text-2); font-size: 14px; transition: color .2s; }
.footer ul a:hover { color: var(--grad-b); }
.footer-contact li { display: flex; gap: 9px; align-items: flex-start; color: var(--text-2); font-size: 14px; }
.footer-contact .ico { color: var(--grad-b); font-size: 14px; flex-shrink: 0; }
.footer-bottom {
  border-top: 1px solid var(--border); padding: 20px 0;
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 10px;
  color: var(--text-3); font-size: 13px;
}
.footer-bottom a { color: var(--text-3); }
.footer-bottom a:hover { color: var(--grad-b); }
.footer-beian { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.footer-beian > span { display: inline-flex; align-items: center; white-space: nowrap; }
.footer-beian .beian-ico { height: 14px; width: auto; max-width: 40px; margin-right: 5px; flex-shrink: 0; object-fit: contain; vertical-align: middle; }

/* ---------------- 卡片 ---------------- */
.card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius-card); padding: 28px;
  transition: all .3s ease; position: relative; overflow: hidden;
}
.card::before {
  content: ""; position: absolute; inset: 0; border-radius: inherit;
  background: radial-gradient(480px 200px at var(--mx, 50%) -20%, rgba(47,107,255,.13), transparent 60%);
  opacity: 0; transition: opacity .3s; pointer-events: none;
}
.card:hover { transform: translateY(-5px); border-color: rgba(47,107,255,.35); background: var(--card-hover); }
.card:hover::before { opacity: 1; }

/* ---------------- 入场动画 ---------------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------------- Toast（底部居中，堆叠，新的在上） ---------------- */
.toast-wrap {
  position: fixed; bottom: 34px; left: 50%; transform: translateX(-50%);
  z-index: 1000; display: flex; flex-direction: column; align-items: center; gap: 10px;
  pointer-events: none; width: min(480px, 90vw);
}
.toast {
  display: flex; align-items: center; gap: 10px; width: 100%;
  padding: 13px 22px; border-radius: 12px; font-size: 14px;
  background: rgba(11,17,32,.95); color: var(--text-1);
  border: 1px solid var(--border-strong);
  box-shadow: 0 10px 34px rgba(0,0,0,.5);
  animation: toastIn .3s ease; pointer-events: auto;
}
.toast.ok { border-color: rgba(52,211,153,.45); }
.toast.ok::before { content: "✓"; color: var(--ok); font-weight: 700; }
.toast.err { border-color: rgba(96,165,250,.5); }
.toast.err::before { content: "!"; color: #7fb0ff; font-weight: 800; }
@keyframes toastIn { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }
.toast.out { animation: toastOut .3s ease forwards; }
@keyframes toastOut { to { opacity: 0; transform: translateY(10px); } }

/* ---------------- 响应式 ---------------- */
@media (max-width: 900px) {
  .nav-links, .nav-cta .btn-ghost { display: none; }
  .nav-toggle { display: flex; }
  .nav-links.open {
    display: flex; position: absolute; top: var(--nav-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; padding: 10px 16px 18px;
    background: rgba(7,11,20,.97); border-bottom: 1px solid var(--border);
    backdrop-filter: blur(16px);
  }
  .nav-links.open a { padding: 13px 16px; }
  .footer-grid { grid-template-columns: 1fr; gap: 34px; padding: 44px 0 34px; }
  .section { padding: 64px 0; }
}
@media (max-width: 560px) {
  .nav-cta .btn { padding: 10px 16px; font-size: 15.5px; font-weight: 600; }
}