/* Set 4: step-driven vertical timeline */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "Avenir Next", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #f3f0ff;
  color: #1e1633;
  line-height: 1.75;
}
.sticky {
  position: sticky;
  top: 0;
  z-index: 8;
  background: #2e1065;
  color: #fff;
}
.sticky-in {
  max-width: 760px;
  margin: 0 auto;
  padding: 14px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #fff;
  text-decoration: none;
  font-weight: 800;
  font-size: 20px;
}
nav a {
  color: #ddd6fe;
  text-decoration: none;
  margin-left: 14px;
  font-size: 14px;
}
nav a.current {
  color: #fff;
  background: #5b21b6;
  padding: 4px 10px;
  border-radius: 4px;
}
.rail {
  max-width: 760px;
  margin: 0 auto;
  padding: 28px 18px 50px;
}
h1 {
  font-size: 28px;
  line-height: 1.4;
  color: #4c1d95;
  margin-bottom: 12px;
}
h2 {
  font-size: 20px;
  color: #5b21b6;
  margin-bottom: 10px;
}
.lead { margin-bottom: 16px; }
.btn {
  display: inline-block;
  background: #5b21b6;
  color: #fff;
  text-decoration: none;
  padding: 12px 20px;
  border-radius: 8px;
  font-weight: 700;
}
.btn:hover { background: #4c1d95; }
.hero-step {
  background: #fff;
  border: 1px solid #ddd6fe;
  padding: 22px;
  border-radius: 12px;
  margin-bottom: 22px;
}
.step {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 14px;
  margin: 0 0 8px;
  position: relative;
}
.step + .step { margin-top: 8px; }
.num {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: #5b21b6;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 800;
  position: relative;
  z-index: 1;
}
.step-body {
  background: #fff;
  border: 1px solid #ddd6fe;
  border-radius: 10px;
  padding: 16px 16px 8px;
}
.timeline { position: relative; }
.timeline:before {
  content: "";
  position: absolute;
  left: 27px;
  top: 20px;
  bottom: 20px;
  width: 2px;
  background: #c4b5fd;
}
p { margin-bottom: 10px; }
ul, ol { margin: 0 0 10px 20px; }
table { width: 100%; border-collapse: collapse; background: #fff; margin: 10px 0 14px; }
th, td { border: 1px solid #ddd6fe; padding: 8px; text-align: left; }
th { background: #5b21b6; color: #fff; }
.faq details {
  background: #fff;
  border: 1px solid #ddd6fe;
  border-radius: 8px;
  padding: 10px 12px;
  margin-bottom: 8px;
}
.faq summary { cursor: pointer; font-weight: 700; color: #4c1d95; }
.faq details p { margin-top: 8px; }
.note { background: #faf5ff; border: 1px solid #c4b5fd; padding: 10px 12px; margin: 10px 0; border-radius: 8px; }
footer {
  background: #1e1633;
  color: #ddd6fe;
  padding: 26px 18px 32px;
  font-size: 13px;
}
.footer-in { max-width: 760px; margin: 0 auto; }
footer a { color: #c4b5fd; margin-right: 12px; }
@media (max-width: 640px) {
  .sticky-in { flex-wrap: wrap; }
  nav { width: 100%; margin-top: 8px; }
  nav a { margin-left: 0; margin-right: 10px; }
}