:root {
  color-scheme: light;
  font-family: "Microsoft YaHei UI", "PingFang SC", "Noto Sans CJK SC", system-ui, sans-serif;
  color: #18273a;
  background: #f3f7fc;
  font-synthesis: none;
}

* { box-sizing: border-box; }
body { margin: 0; }
a { color: inherit; }
img { display: block; max-width: 100%; }
a:focus-visible { outline: 3px solid #105fc2; outline-offset: 5px; }

.shell {
  width: min(1120px, 100% - 96px);
  margin: 0 auto;
}

.header {
  height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid #dce6f2;
}

.brand,
.header-link {
  text-decoration: none;
  font-weight: 650;
}

.brand { display: inline-flex; align-items: center; gap: 11px; }
.header-link { font-size: 14px; color: #475d77; }
.header-link:hover { color: #005bbf; text-decoration: underline; text-underline-offset: 4px; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.19fr);
  gap: 60px;
  align-items: center;
  padding-block: 66px 63px;
}

.intro h1 {
  margin: 0 0 23px;
  font-size: clamp(54px, 7vw, 92px);
  line-height: 1.08;
  letter-spacing: -.055em;
  font-weight: 750;
}

.intro p {
  max-width: 380px;
  margin: 0;
  color: #435970;
  font-size: 17px;
  line-height: 1.85;
}

.download {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  justify-content: center;
  padding: 15px 22px;
  margin-top: 31px;
  border-radius: 9px;
  background: #005ec8;
  color: #fff;
  text-decoration: none;
  font-weight: 650;
  transition: background-color .15s ease;
}

.download:hover { background: #004d9f; }
.arrow { font-size: 21px; line-height: 1; }
.intro .build { margin-top: 10px; color: #52677e; font-size: 13px; }

.preview {
  min-width: 0;
  margin: 0;
  padding: clamp(22px, 4vw, 54px);
  border: 1px solid #c6dcf2;
  border-radius: 22px;
  background: #dcecfb;
}

.preview img {
  width: 100%;
  height: auto;
  border: 1px solid #b3c8df;
  border-radius: 10px;
  box-shadow: 0 16px 42px #163b672e;
}

.setup {
  border-top: 1px solid #dce6f2;
  padding-block: 32px 60px;
}

.setup h2 { margin: 0 0 24px; font-size: 24px; }
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px; }
.steps h3 { margin: 0 0 7px; font-size: 16px; }
.steps p { margin: 0; color: #435970; line-height: 1.8; font-size: 14px; }

@media (max-width: 830px) {
  .shell { width: min(560px, 100% - 40px); }
  .hero { grid-template-columns: 1fr; gap: 32px; padding-block: 42px; }
  .intro h1 { font-size: clamp(51px, 11vw, 73px); }
  .preview { padding: clamp(18px, 5vw, 40px); }
}

@media (max-width: 520px) {
  .header { height: 64px; }
  .steps { grid-template-columns: 1fr; gap: 22px; }
}