:root {
  --bg: #ffffff;
  --surface: #ffffff;
  --text: #17253a;
  --muted: #5c6f86;
  --primary: #2496ed;
  --line: #deebf8;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Arial, "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}
.container { width: min(1120px, 92%); margin: 0 auto; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(255,255,255,0.9);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}
.nav {
  padding: 12px 0;
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 26px;
}
.brand {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  margin-left: 12px;
}
.brand img {
  width: 32px;
  height: 32px;
  display: block;
  object-fit: contain;
  border-radius: 50%;
}
.brand span {
  white-space: nowrap;
  line-height: 1;
}
nav a {
  text-decoration: none;
  color: var(--primary);
  margin-right: 18px;
  font-weight: 700;
}
.nav-twitter {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
  color: var(--primary);
  font-weight: 700;
  text-decoration: none;
}
.nav-twitter .tw-icon {
  width: 1.5em;
  height: 1.5em;
  display: block;
  fill: var(--primary);
}
.hero {
  position: relative;
  overflow: hidden;
  padding: 84px 0 70px;
}
.hero-simple { padding: 64px 0 40px; }
.hero-center { position: relative; text-align: center; }
.hero-brand { display: inline-flex; flex-direction: column; align-items: center; gap: 6px; }
.hero-logo {
  width: 84px;
  height: 84px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: 0 10px 24px rgba(27, 83, 139, 0.15);
}
.hero-title {
  margin: 10px 0 0;
  font-size: 32px;
  letter-spacing: 0.2px;
}
.hero-subtitle {
  margin: 0;
  color: var(--muted);
  font-weight: 700;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background: #ffffff;
}
.hero-inner {
  position: relative;
  display: grid;
  gap: 22px;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
}
.eyebrow {
  margin: 0;
  color: var(--primary);
  font-weight: 700;
  letter-spacing: 0.3px;
}
h1 {
  font-size: clamp(30px, 5vw, 54px);
  line-height: 1.15;
  margin: 8px 0 12px;
}
.lead {
  color: var(--muted);
  max-width: 640px;
}
.download-top { display: none; }
.btn {
  border-radius: 10px;
  padding: 11px 20px;
  text-decoration: none;
  font-weight: 700;
}
.btn.primary { background: var(--primary); color: #fff; }
.btn.ghost { border: 1px solid var(--line); color: var(--text); background: #fff; }
.hero-art { display: none; }
.section { padding: 68px 0; }
.section h2 { margin: 0 0 16px; font-size: 32px; }
.sub { color: var(--muted); margin-top: -4px; }
.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px;
}
.card img { width: 72px; height: 72px; }
.card h3 { margin: 14px 0 8px; }
.card p { margin: 0; color: var(--muted); }
.alt {
  background: #fff;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.split {
  display: grid;
  grid-template-columns: 1fr 0.9fr;
  align-items: center;
  gap: 20px;
}
.split img { width: 100%; max-width: 420px; justify-self: end; }
ul { padding-left: 18px; }
.download-like {
  padding-top: 24px;
  max-width: 980px;
  margin: 0 auto;
  text-align: center;
}
.download-like__desktop { text-align: center; }
.download-like__desktop img {
  max-width: 520px;
  width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
}
.download-like__link {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  min-width: 260px;
  height: 44px;
  margin-top: 10px;
  padding: 0 14px;
  background: #f4f9ff;
  border: 1px solid #cfe6ff;
  border-radius: 12px;
  color: #1f78c8;
  text-decoration: none;
  font-weight: 700;
  justify-content: center;
  white-space: nowrap;
}
.dl-ico img { width: 18px; height: 18px; display: block; }
.download-like__mobile {
  margin-top: 18px;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  gap: 0;
}
.download-like__item {
  width: 340px;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.download-like__item + .download-like__item {
  margin-left: -24px;
}
.download-like__item > img {
  width: 100%;
  height: 220px;
  object-fit: contain;
  object-position: center bottom;
  animation: floatY 4.6s ease-in-out infinite;
}
.img-desktop {
  animation: floatDesk 5.2s ease-in-out infinite;
}
.img-android {
  animation: floatAndroid 4.6s ease-in-out infinite;
}
.img-ios {
  animation: floatIos 4.9s ease-in-out infinite;
}
.download-item {
  display: inline-block;
  background: transparent;
  border: 0;
  border-radius: 12px;
  padding: 2px 8px;
  text-align: center;
  color: #1f78c8;
  text-decoration: none;
  font-weight: 700;
}
.sub-link {
  margin-top: 10px;
}
.sub-link a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 700;
  font-size: 14px;
}
@keyframes floatY {
  0% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
  100% { transform: translateY(0); }
}
@keyframes floatDesk {
  0% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
  100% { transform: translateY(0); }
}
@keyframes floatAndroid {
  0% { transform: translateY(0) rotate(-0.6deg); }
  50% { transform: translateY(-9px) rotate(0.6deg); }
  100% { transform: translateY(0) rotate(-0.6deg); }
}
@keyframes floatIos {
  0% { transform: translateY(0) rotate(0.6deg); }
  50% { transform: translateY(-9px) rotate(-0.6deg); }
  100% { transform: translateY(0) rotate(0.6deg); }
}
details {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px;
  margin-bottom: 10px;
}
summary { cursor: pointer; font-weight: 700; }
.site-footer {
  border-top: 1px solid var(--line);
  padding: 24px 0;
}
.footer-wrap {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
@media (max-width: 900px) {
  .hero-inner, .cards, .split { grid-template-columns: 1fr; }
  .hero-art, .split img { justify-self: start; }
  .download-top { flex-direction: column; align-items: flex-start; }
  .download-like__mobile { flex-direction: column; align-items: center; gap: 16px; }
  .download-like__item + .download-like__item { margin-left: 0; }
  .download-like__item img { height: auto; max-height: 280px; }
  .download-like__link { min-width: 240px; }
  nav { display: none; }
}