:root {
  --primary: #1f8fff;
  --primary-dark: #0f6fd6;
  --ink: #1f2733;
  --muted: #6b7686;
  --bg: #f5f8fc;
  --alt: #eef4fb;
  --line: #e2e9f2;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(31, 143, 255, .12);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
}

a { color: inherit; text-decoration: none; }

.wrap { width: min(1080px, 92vw); margin: 0 auto; }

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform .12s ease, box-shadow .12s ease, background .12s ease;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--primary); color: #fff; box-shadow: var(--shadow); }
.btn-primary:hover { background: var(--primary-dark); }
.btn-ghost { background: #fff; color: var(--primary); border-color: var(--primary); }
.btn-ghost:hover { background: var(--alt); }

/* 导航 */
.nav {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; gap: 20px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.brand-logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--primary), #46b1ff);
  color: #fff; display: grid; place-items: center; font-size: 18px;
}
.brand-name { font-size: 17px; }
.nav-links { display: flex; gap: 22px; margin-left: auto; color: var(--muted); font-size: 15px; }
.nav-links a:hover { color: var(--primary); }
.nav-cta { margin-left: 8px; }

/* 首屏 */
.hero { background: linear-gradient(180deg, #eaf3ff 0%, var(--bg) 100%); padding: 64px 0 72px; }
.hero-inner { display: grid; grid-template-columns: 1.1fr .9fr; gap: 40px; align-items: center; }
.hero h1 { font-size: 40px; line-height: 1.25; margin: 0 0 16px; }
.lead { font-size: 17px; color: var(--muted); margin: 0 0 24px; }
.lead.center { text-align: center; }
.hero-actions { display: flex; gap: 14px; margin-bottom: 24px; }
.hero-points { list-style: none; padding: 0; margin: 0; color: var(--muted); }
.hero-points li { margin: 6px 0; }
.hero-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow);
}
.kb { font-family: "PingFang SC", system-ui, sans-serif; }
.kb-row { display: flex; gap: 10px; margin-bottom: 10px; }
.kb-row span {
  flex: 1; text-align: center; padding: 14px 0; background: var(--alt);
  border-radius: 10px; font-weight: 600; color: var(--primary-dark);
}
.kb-cand { margin-top: 4px; padding: 12px; background: #fff; border: 1px dashed var(--line); border-radius: 10px; color: var(--ink); font-size: 15px; }

/* 通用区块 */
.section { padding: 64px 0; }
.section-alt { background: var(--alt); }
.section-title { text-align: center; font-size: 28px; margin: 0 0 12px; }
.section .lead { margin-bottom: 36px; }

/* 卡片 */
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; transition: transform .15s ease, box-shadow .15s ease; }
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.card-ico { font-size: 30px; margin-bottom: 10px; }
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 14px; }

/* 下载 */
.download-inner { text-align: center; }
.dl-box {
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 26px; max-width: 640px; margin: 0 auto; box-shadow: var(--shadow); text-align: left;
}
.dl-name { font-size: 18px; font-weight: 700; }
.dl-meta { color: var(--muted); font-size: 14px; }
.dl-tip { color: var(--muted); font-size: 14px; margin-top: 16px; }

/* 客服 */
.support-grid { display: grid; grid-template-columns: .85fr 1.15fr; gap: 28px; align-items: start; }
.support-contact { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.contact-item { display: flex; gap: 14px; align-items: center; padding: 10px 0; border-bottom: 1px dashed var(--line); }
.contact-item:last-of-type { border-bottom: none; }
.contact-ico { font-size: 22px; }
.contact-label { color: var(--muted); font-size: 13px; }
.contact-value { font-size: 18px; font-weight: 700; }
.contact-value a:hover { color: var(--primary); }
.qr { text-align: center; margin-top: 18px; }
.qr img { width: 160px; height: 160px; object-fit: cover; border: 1px solid var(--line); border-radius: 12px; }
.qr-text { margin-top: 8px; color: var(--muted); font-size: 14px; }

.cs-form { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; }
.cs-form h3 { margin: 0 0 4px; font-size: 20px; }
.cs-sub { color: var(--muted); font-size: 14px; margin: 0 0 18px; }
.cs-form label { display: block; margin-bottom: 14px; }
.cs-form label span { display: block; font-size: 14px; margin-bottom: 6px; color: var(--ink); }
.cs-form input, .cs-form textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 15px; font-family: inherit; resize: vertical; background: #fbfdff;
}
.cs-form input:focus, .cs-form textarea:focus { outline: none; border-color: var(--primary); background: #fff; }
.cs-form .btn { width: 100%; margin-top: 4px; }
.tip { margin-top: 14px; font-size: 14px; min-height: 20px; }
.tip.ok { color: #1aa463; }
.tip.err { color: #e0483c; }

/* 页脚 */
.footer { background: #11203a; color: #c7d3e6; padding: 36px 0; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; }
.footer .brand-name { color: #fff; }
.footer-meta p { margin: 4px 0; font-size: 14px; }

/* 响应式 */
@media (max-width: 860px) {
  .hero-inner, .support-grid { grid-template-columns: 1fr; }
  .cards { grid-template-columns: repeat(2, 1fr); }
  .nav-links { display: none; }
  .hero h1 { font-size: 32px; }
  .dl-box { flex-direction: column; text-align: center; }
}
@media (max-width: 520px) {
  .cards { grid-template-columns: 1fr; }
}

/* FAQ 折叠区 */
.faq{display:flex;flex-direction:column;gap:10px;max-width:840px;margin:0 auto}
.faq-item{background:#fff;border:1px solid var(--line);border-radius:12px;padding:2px 16px;box-shadow:var(--shadow)}
.faq-item summary{cursor:pointer;padding:13px 0;font-weight:600;color:#1f2733;list-style:none;outline:none}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::before{content:"＋";color:var(--primary);font-weight:700;margin-right:10px}
.faq-item[open] summary::before{content:"－"}
.faq-item p{margin:0 0 14px;color:#46506a;font-size:14px;line-height:1.7}