:root {
  --blue: #3b6cff;
  --blue-deep: #2454e6;
  --yellow: #f5b400;
  --ink: #1a1c2c;
  --muted: #5c6178;
  --card: #fffdf8;
  --line: #e7e2d4;
  --shadow: 0 22px 50px rgba(26, 28, 44, 0.18);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  background: var(--blue);
  min-height: 100vh;
}
a { color: inherit; }
img { max-width: 100%; display: block; }

.topbar, .bottombar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 22px 36px;
  color: #fff;
  position: relative;
  z-index: 3;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.02em;
}
.mark {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: #fff;
  display: grid;
  place-items: center;
  color: var(--blue);
  font-weight: 800;
}
.nav {
  display: flex;
  gap: 8px 22px;
  flex-wrap: wrap;
  justify-content: center;
}
.nav a {
  text-decoration: none;
  color: rgba(255,255,255,0.88);
  font-size: 15px;
}
.nav a.active, .nav a:hover { color: #fff; }
.nav a.active { border-bottom: 2px solid #fff; padding-bottom: 2px; }

.hero {
  min-height: calc(100vh - 150px);
  display: grid;
  grid-template-columns: 1fr 1.15fr 1fr;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding: 10px 40px 40px;
}
.blob {
  position: absolute;
  left: 18%;
  top: -20%;
  width: 46vw;
  height: 140%;
  background: var(--yellow);
  border-radius: 50% 50% 46% 54%;
  transform: rotate(8deg);
  z-index: 0;
}
.side-label {
  position: relative;
  z-index: 2;
  color: #fff;
  font-size: clamp(28px, 3vw, 42px);
  font-weight: 700;
  text-decoration: none;
  justify-self: center;
}
.side-label span {
  display: inline-block;
  border-bottom: 3px solid #fff;
  padding-bottom: 6px;
}
.side-label.dark { color: var(--ink); }
.side-label.dark span { border-color: var(--ink); }

.stage {
  position: relative;
  z-index: 2;
  height: 460px;
  perspective: 1200px;
}
.card {
  position: absolute;
  inset: 20px 8% auto;
  height: 420px;
  background: var(--card);
  border-radius: 28px;
  box-shadow: var(--shadow);
  padding: 28px 28px 24px;
  transition: transform 0.55s cubic-bezier(.2,.8,.2,1), opacity 0.4s;
  overflow: hidden;
}
.card h2 { margin: 8px 0 12px; font-size: 32px; line-height: 1.25; }
.card p { margin: 0; color: var(--muted); line-height: 1.7; font-size: 16px; }
.chip {
  display: inline-block;
  background: var(--blue);
  color: #fff;
  border-radius: 999px;
  font-size: 12px;
  padding: 4px 10px;
}
.shapes { position: absolute; inset: auto 0 0 0; height: 160px; pointer-events: none; }
.blob-s {
  position: absolute;
  border-radius: 50%;
}
.card[data-i="0"] { transform: rotate(-8deg) translate(-18px, 8px); z-index: 3; }
.card[data-i="1"] { transform: rotate(6deg) translate(36px, 18px); z-index: 2; }
.card[data-i="2"] { transform: rotate(2deg) translate(8px, 36px) scale(0.96); z-index: 1; opacity: 0.95; }
.card.is-back { opacity: 0; pointer-events: none; }

.mini-window {
  width: 150px;
  height: 110px;
  border: 3px solid var(--ink);
  border-radius: 12px;
  position: absolute;
  left: 28px;
  bottom: 28px;
  background: #fff;
}
.mini-window i {
  position: absolute;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 3px solid var(--ink);
  display: grid;
  place-items: center;
  font-style: normal;
  font-weight: 800;
}
.tri {
  width: 0; height: 0;
  border-left: 22px solid transparent;
  border-right: 22px solid transparent;
  border-bottom: 36px solid #f0c43a;
  position: absolute;
  right: 36px;
  bottom: 70px;
}
.sq {
  width: 42px; height: 42px;
  background: #3b6cff;
  position: absolute;
  right: 70px;
  bottom: 24px;
}

.page {
  position: relative;
  z-index: 1;
  padding: 10px 28px 48px;
}
.sheet {
  max-width: 980px;
  margin: 0 auto;
  background: #fffdf8;
  border-radius: 28px;
  padding: 36px 40px 48px;
  box-shadow: var(--shadow);
}
.crumbs { color: var(--muted); font-size: 14px; margin-bottom: 12px; }
.crumbs a { color: var(--blue-deep); }
h1 { font-size: clamp(28px, 4vw, 40px); margin: 0 0 12px; line-height: 1.3; }
.lead { font-size: 18px; color: #3a3f55; line-height: 1.8; }
.sheet h2 { margin: 28px 0 10px; font-size: 22px; }
.sheet p, .sheet li { line-height: 1.9; font-size: 16.5px; color: #2a2e40; }
.sheet ul { padding-left: 1.2em; }
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 18px;
}
.tile {
  background: #f4f7ff;
  border-radius: 18px;
  padding: 16px 18px;
  text-decoration: none;
  border: 1px solid #e3e9ff;
}
.tile strong { display: block; margin-bottom: 6px; }
.tile span { color: var(--muted); font-size: 14px; line-height: 1.6; }
.note {
  margin-top: 28px;
  background: #fff6d8;
  border-radius: 16px;
  padding: 14px 16px;
  font-size: 14px;
  line-height: 1.7;
}
table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0 8px;
  font-size: 15px;
}
th, td { border-bottom: 1px solid var(--line); text-align: left; padding: 10px 8px; }
th { background: #f7f4ea; }

.bottombar { font-size: 14px; }
.bottombar a { color: #fff; text-decoration: none; }
.pills {
  display: flex;
  background: #111;
  border-radius: 999px;
  padding: 6px;
  gap: 4px;
}
.pills button {
  border: 0;
  background: transparent;
  color: #fff;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 16px;
}
.pills button.on { background: #fff; color: #111; }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; min-height: auto; padding-bottom: 20px; }
  .blob { left: -20%; width: 140%; height: 70%; top: 18%; }
  .side-label { margin: 12px 0; }
  .stage { height: 440px; }
  .grid { grid-template-columns: 1fr; }
  .sheet { padding: 24px 18px 32px; }
  .topbar, .bottombar { padding: 16px; }
  .nav { display: none; }
  .nav.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 12px;
    right: 12px;
    background: #1d4ed8;
    padding: 14px;
    border-radius: 16px;
  }
  .menu-btn { display: inline-flex !important; }
}
.menu-btn {
  display: none;
  border: 0;
  background: #fff;
  color: var(--blue);
  border-radius: 999px;
  padding: 8px 14px;
  font-weight: 700;
  cursor: pointer;
}

.band { position: relative; padding: 72px 6vw; }
.band h2 { font-size: clamp(28px, 4vw, 46px); margin: 0 0 14px; line-height: 1.2; }
.band p { font-size: 17px; line-height: 1.85; }
.cream { background: #fff8ec; color: var(--ink); }
.ink { background: #14182b; color: #f4f1ea; }
.sun { background: var(--yellow); color: #1a1c2c; }
.band a.more { color: inherit; font-weight: 700; }

.marquee {
  background: #111;
  color: #fff;
  overflow: hidden;
  white-space: nowrap;
  padding: 14px 0;
  font-weight: 700;
  letter-spacing: 0.08em;
}
.marquee span { display: inline-block; padding-left: 100%; animation: slide 22s linear infinite; }
@keyframes slide { to { transform: translateX(-100%); } }

.split {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 40px;
  align-items: center;
  max-width: 1180px;
  margin: 0 auto;
}
.split > * { min-width: 0; }
.split.prose {
  grid-template-columns: minmax(0, 760px);
}
.band h2, .band p { overflow-wrap: anywhere; }
.giant {
  font-size: clamp(92px, 12vw, 168px);
  line-height: 0.85;
  font-weight: 800;
  margin: 0;
}
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 1180px;
  margin: 28px auto 0;
}
.step {
  background: #fff;
  color: var(--ink);
  border-radius: 24px;
  min-height: 240px;
  padding: 22px;
  box-shadow: var(--shadow);
}
.step em { font-style: normal; font-size: 13px; letter-spacing: 0.12em; color: var(--blue); }
.step h3 { margin: 12px 0; font-size: 22px; }

.lanes {
  display: grid;
  grid-template-columns: 1.3fr 0.7fr;
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto;
}
.lane {
  border-radius: 28px;
  padding: 28px;
  min-height: 220px;
  text-decoration: none;
  color: inherit;
  display: block;
}
.lane.tall { min-height: 460px; background: #fff; }
.stack-lanes { display: grid; gap: 18px; }
.lane.y { background: var(--yellow); }
.lane.b { background: #dfe8ff; }
.numrow { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.numrow i {
  font-style: normal;
  width: 42px; height: 42px;
  border-radius: 50%;
  display: grid; place-items: center;
  background: var(--ink); color: #fff; font-weight: 700;
}

.page-hero {
  padding: 28px 6vw 10px;
  color: #fff;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 24px;
  align-items: end;
}
.page-hero h1 { font-size: clamp(36px, 5vw, 64px); margin: 8px 0; }
.kicker { letter-spacing: 0.14em; font-size: 13px; opacity: 0.85; }
.page-hero p { font-size: 18px; line-height: 1.7; max-width: 46ch; }

.rail {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 28px;
  max-width: 1100px;
  margin: 0 auto;
}
.rail aside {
  position: sticky;
  top: 16px;
  align-self: start;
  font-weight: 700;
}
.blocks { display: grid; gap: 18px; }
.block {
  background: #fffdf8;
  border-radius: 24px;
  padding: 22px 24px;
}
.block h2 { margin-top: 0; }

.qa {
  max-width: 980px;
  margin: 0 auto;
  display: grid;
  gap: 0;
}
.qa details {
  background: #fffdf8;
  border-bottom: 1px solid #eadfbf;
  padding: 8px 22px 16px;
}
.qa details:first-child { border-radius: 24px 24px 0 0; }
.qa details:last-child { border-radius: 0 0 24px 24px; }
.qa summary { cursor: pointer; font-size: 20px; font-weight: 700; padding: 14px 0; }
.qa p { margin-top: 0; }

.mosaic {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 16px;
  max-width: 1100px;
  margin: 0 auto;
}
.mosaic article {
  background: #fffdf8;
  border-radius: 28px;
  padding: 26px;
}
.mosaic article.span { grid-column: 1 / -1; background: #14182b; color: #f6f3ea; }

.site-foot {
  background: #0e1224;
  color: #efeae0;
  padding: 48px 6vw 20px;
}
.foot-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 28px;
  max-width: 1100px;
  margin: 0 auto 28px;
}
.site-foot a { color: #fff; text-decoration: none; }
.site-foot ul { list-style: none; padding: 0; margin: 0; line-height: 2; }
.site-foot h3 { margin: 0 0 8px; font-size: 15px; letter-spacing: 0.08em; }
.foot-copy { color: #c9c3b6; line-height: 1.7; font-size: 14px; }
.foot-bar {
  border-top: 1px solid rgba(255,255,255,0.12);
  padding-top: 14px;
  font-size: 13px;
  color: #b7b1a6;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  max-width: 1100px;
  margin: 0 auto;
}

@media (max-width: 900px) {
  .split, .steps, .lanes, .page-hero, .rail, .mosaic, .foot-grid { grid-template-columns: 1fr; }
  .rail aside { position: static; }
  .step { min-height: 0; }
  .lane.tall { min-height: 0; }
}