/* ===== 基础 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --brand: #4f46e5;
  --brand-dark: #4338ca;
  --accent: #7c3aed;
  --ink: #0f172a;
  --muted: #64748b;
  --bg: #ffffff;
  --bg-alt: #f5f6fb;
  --line: #e2e8f0;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(15, 23, 42, .08);
}
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  line-height: 1.7;
  background: var(--bg);
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }
section[id] { scroll-margin-top: 70px; }

/* ===== 顶部导航 ===== */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { max-width: 1080px; margin: 0 auto; padding: 12px 20px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.logo { font-size: 18px; }
.logo b { font-weight: 800; }
.menu { display: flex; align-items: center; gap: 22px; font-size: 15px; color: var(--muted); }
.menu a:hover { color: var(--brand); }
.menu-toggle { display: none; background: none; border: 0; font-size: 22px; cursor: pointer; }

/* ===== 按钮 ===== */
.btn {
  display: inline-block; padding: 10px 20px; border-radius: 10px;
  background: var(--bg-alt); border: 1px solid var(--line);
  font-size: 15px; cursor: pointer; text-align: center; transition: .2s;
}
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-primary { background: linear-gradient(135deg, var(--brand), var(--accent)); color: #fff; border: 0; }
.btn-primary:hover { filter: brightness(1.08); }
.btn-ghost { background: transparent; color: #fff; border: 1px solid rgba(255,255,255,.55); }
.btn-lg { padding: 14px 26px; font-size: 16px; }
.btn-small { padding: 7px 14px; font-size: 14px; background: linear-gradient(135deg, var(--brand), var(--accent)); color:#fff; border: 0; }

/* ===== Hero ===== */
.hero {
  background: radial-gradient(1000px 500px at 15% -10%, rgba(124,58,237,.45), transparent 60%),
              radial-gradient(900px 480px at 90% 0%, rgba(79,70,229,.5), transparent 55%),
              linear-gradient(160deg, #1e1b4b 0%, #312e81 45%, #4c1d95 100%);
  color: #fff; padding: 84px 20px 90px; text-align: center;
}
.hero-inner { max-width: 820px; margin: 0 auto; }
.hero-eyebrow { display: inline-block; font-size: 14px; letter-spacing: .08em; color: #c7d2fe; border: 1px solid rgba(199,210,254,.35); padding: 5px 14px; border-radius: 999px; margin-bottom: 20px; }
.hero h1 { font-size: 52px; line-height: 1.25; font-weight: 800; letter-spacing: .02em; }
.hero-sub { margin: 18px 0 28px; font-size: 19px; color: #e0e7ff; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero-note { margin-top: 26px; font-size: 13px; color: #a5b4fc; }
.hero-note strong { color: #fde68a; }

/* ===== 区块 ===== */
.section { padding: 72px 20px; }
.section-alt { background: var(--bg-alt); }
.container { max-width: 1080px; margin: 0 auto; }
.section-title { font-size: 32px; text-align: center; font-weight: 800; }
.section-sub { text-align: center; color: var(--muted); margin: 8px 0 40px; }

/* ===== 服务卡片 ===== */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 24px; transition: .2s; }
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: #c7d2fe; }
.card-icon { font-size: 34px; margin-bottom: 10px; }
.card h3 { font-size: 19px; margin-bottom: 8px; }
.card p { color: var(--muted); font-size: 14.5px; min-height: 44px; }
.card-price { margin-top: 14px; font-size: 22px; font-weight: 800; color: var(--brand); }
.card-price span { font-size: 13px; color: var(--muted); font-weight: 400; }

/* ===== 套餐 ===== */
.plans { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; align-items: stretch; }
.plan { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 30px 26px; text-align: center; position: relative; display: flex; flex-direction: column; gap: 16px; }
.plan h3 { font-size: 18px; }
.plan-price { font-size: 34px; font-weight: 800; color: var(--ink); }
.plan-price small { font-size: 14px; color: var(--muted); font-weight: 400; }
.plan ul { list-style: none; text-align: left; flex: 1; display: grid; gap: 8px; color: var(--muted); font-size: 14.5px; }
.plan ul li::before { content: "✓ "; color: var(--brand); font-weight: 700; }
.plan-featured { border: 2px solid var(--brand); box-shadow: var(--shadow); }
.plan-badge { position: absolute; top: -13px; left: 50%; transform: translateX(-50%); background: linear-gradient(135deg, var(--brand), var(--accent)); color: #fff; font-size: 13px; padding: 3px 14px; border-radius: 999px; }

/* ===== 流程 ===== */
.steps { list-style: none; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; counter-reset: step; }
.steps li { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 18px; position: relative; }
.steps b { position: absolute; top: -14px; left: 18px; width: 30px; height: 30px; border-radius: 50%; background: linear-gradient(135deg, var(--brand), var(--accent)); color: #fff; display: grid; place-items: center; font-size: 15px; }
.steps h3 { font-size: 16px; margin: 8px 0 4px; }
.steps p { font-size: 13.5px; color: var(--muted); }

/* ===== FAQ ===== */
.faq { max-width: 760px; margin: 0 auto; display: grid; gap: 12px; }
.faq details { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 4px 18px; }
.faq summary { cursor: pointer; padding: 14px 0; font-weight: 600; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq summary::after { content: "+"; font-size: 20px; color: var(--brand); }
.faq details[open] summary::after { content: "−"; }
.faq p { color: var(--muted); padding: 0 0 16px; font-size: 14.5px; }

/* ===== 下单区 ===== */
.order-box { max-width: 640px; margin: 0 auto; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow); display: grid; gap: 8px; }
.order-box label { font-size: 14px; font-weight: 600; margin-top: 8px; }
.order-box select, .order-box textarea {
  width: 100%; padding: 12px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 15px; font-family: inherit; background: #fff; color: var(--ink);
}
.order-box select:focus, .order-box textarea:focus { outline: 2px solid #c7d2fe; border-color: var(--brand); }
.checkbox { display: flex; align-items: center; gap: 8px; font-weight: 400 !important; margin: 10px 0 0 !important; }
.estimate { font-size: 18px; margin: 12px 0 4px; }
.estimate b { color: var(--brand); font-size: 24px; }
.order-actions { margin-top: 6px; }
.wechat-line { margin-top: 16px; text-align: center; font-size: 15px; }
.wechat-id { display: inline-flex; align-items: center; gap: 6px; margin-left: 6px; padding: 6px 14px; border: 1px dashed var(--brand); border-radius: 999px; color: var(--brand); background: #eef2ff; font-size: 15px; cursor: pointer; }
.wechat-id:hover { background: #e0e7ff; }
.hint { text-align: center; color: var(--muted); font-size: 13px; margin-top: 10px; }
.copy-tip { text-align: center; color: #16a34a; font-size: 14px; font-weight: 600; min-height: 22px; }

/* ===== 页脚 ===== */
.footer { background: #0f172a; color: #94a3b8; text-align: center; padding: 34px 20px; font-size: 14px; display: grid; gap: 6px; }
.footer .js-wechat { color: #e2e8f0; }
.footer-note { font-size: 12.5px; color: #64748b; margin-top: 8px; }

/* ===== 响应式 ===== */
@media (max-width: 920px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .plans { grid-template-columns: 1fr; max-width: 420px; margin: 0 auto; }
  .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .menu {
    position: fixed; inset: 0 0 auto 0; top: 58px; flex-direction: column; align-items: stretch;
    background: #fff; padding: 16px 24px 24px; border-bottom: 1px solid var(--line);
    display: none; gap: 14px;
  }
  .menu.open { display: flex; }
  .menu-toggle { display: block; }
  .hero { padding: 60px 18px 66px; }
  .hero h1 { font-size: 36px; }
  .hero-sub { font-size: 16px; }
  .cards { grid-template-columns: 1fr; }
  .section-title { font-size: 26px; }
  .only-mobile { display: none; }
}