/* Weey — brand yellow #FFD238 + ink #0C0D13. Light and dark follow the system. */
:root {
  --yellow: #ffd238;
  --ink: #0c0d13;
  --hero-bg: #ffd238;
  --hero-fg: #0c0d13;
  --hero-sub: rgba(12, 13, 19, 0.72);
  --pill-bg: rgba(12, 13, 19, 0.08);
  --pill-bg-hover: rgba(12, 13, 19, 0.14);
  --page: #f6f6f4;
  --card: #ffffff;
  --fg: #0c0d13;
  --muted: #6b6d78;
  --line: rgba(12, 13, 19, 0.08);
  --icon-bg: #0c0d13;
  --icon-fg: #ffd238;
}
@media (prefers-color-scheme: dark) {
  :root {
    --hero-bg: #0c0d13;
    --hero-fg: #ffffff;
    --hero-sub: rgba(255, 255, 255, 0.66);
    --pill-bg: rgba(255, 210, 56, 0.12);
    --pill-bg-hover: rgba(255, 210, 56, 0.2);
    --page: #050507;
    --card: #15151b;
    --fg: #f4f4f5;
    --muted: #9c9eac;
    --line: rgba(255, 255, 255, 0.08);
    --icon-bg: #ffd238;
    --icon-fg: #0c0d13;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--page); color: var(--fg);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { display: block; }

/* ---------- Hero ---------- */
.hero {
  position: relative; background: var(--hero-bg); color: var(--hero-fg);
  padding: 0 24px 128px; text-align: center;
  border-bottom-left-radius: 50% 90px; border-bottom-right-radius: 50% 90px;
}
.hero-nav {
  max-width: 1120px; margin: 0 auto; height: 72px;
  display: flex; align-items: center; justify-content: flex-end; gap: 24px;
  font-size: 14px; color: var(--hero-sub);
}
.hero-nav a:hover { color: var(--hero-fg); }
.hero-brand { display: flex; align-items: center; justify-content: center; gap: 16px; margin-top: 64px; }
.hero-brand img { width: 64px; height: 64px; border-radius: 16px; }
.hero-brand span { font-size: 46px; font-weight: 800; letter-spacing: -0.5px; }
@media (prefers-color-scheme: light) {
  .hero-brand img { box-shadow: 0 8px 24px rgba(12, 13, 19, 0.18); }
}
.hero-tagline { margin: 28px 0 0; font-size: 19px; line-height: 1.8; color: var(--hero-sub); }
.hero-tagline strong { color: var(--hero-fg); font-weight: 600; }

.platforms { display: flex; justify-content: center; gap: 28px; margin-top: 52px; }
.platform {
  width: 108px; height: 108px; border-radius: 50%;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px;
  background: var(--pill-bg); color: var(--hero-fg); font-size: 14px; font-weight: 500;
  border: 0; cursor: pointer; font-family: inherit;
  transition: background .15s ease, transform .15s ease;
}
.platform:hover { background: var(--pill-bg-hover); transform: translateY(-2px); }
.platform:active { transform: scale(0.97); }
.platform svg { width: 30px; height: 30px; fill: currentColor; }

/* ---------- Advantages ---------- */
.features {
  max-width: 1120px; margin: 72px auto 0; padding: 0 24px;
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; position: relative;
}
.feature {
  background: var(--card); border-radius: 16px; padding: 36px 24px 32px; text-align: center;
  border: 1px solid var(--line);
}
.feature .ico {
  width: 52px; height: 52px; border-radius: 16px; margin: 0 auto 18px;
  display: grid; place-items: center; background: var(--icon-bg); color: var(--icon-fg);
}
.feature .ico svg { width: 26px; height: 26px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.feature h3 { margin: 0 0 8px; font-size: 18px; }
.feature p { margin: 0; font-size: 14.5px; line-height: 1.7; color: var(--muted); }

.more {
  max-width: 1120px; margin: 20px auto 0; padding: 0 24px;
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}
.more .feature { text-align: left; display: flex; gap: 16px; align-items: flex-start; padding: 26px 24px; }
.more .feature .ico { margin: 0; flex: none; width: 44px; height: 44px; border-radius: 13px; }
.more .feature .ico svg { width: 22px; height: 22px; }
.more .feature h3 { font-size: 16.5px; margin-bottom: 4px; }

/* ---------- Footer ---------- */
.site-footer { max-width: 1120px; margin: 0 auto; padding: 72px 24px 48px; text-align: center; color: var(--muted); font-size: 13px; }
.site-footer nav { display: flex; justify-content: center; gap: 28px; margin-bottom: 12px; font-size: 14px; }
.site-footer nav a:hover { color: var(--fg); }

/* ---------- Download dialog ---------- */
.dialog-mask {
  position: fixed; inset: 0; z-index: 40; display: none; align-items: center; justify-content: center;
  background: rgba(0, 0, 0, 0.5); padding: 24px;
}
.dialog-mask.show { display: flex; }
.dialog {
  position: relative; width: 100%; max-width: 420px; border-radius: 16px; padding: 44px 40px 40px;
  background: var(--card); color: var(--fg); text-align: center;
}
.dialog h2 { margin: 0 0 28px; font-size: 22px; }
.dialog .close {
  position: absolute; top: 14px; right: 14px; width: 36px; height: 36px; border-radius: 50%;
  border: 0; background: transparent; color: var(--muted); cursor: pointer; display: grid; place-items: center;
}
.dialog .close:hover { background: var(--line); color: var(--fg); }
.dialog .close svg { width: 18px; height: 18px; stroke: currentColor; stroke-width: 2; stroke-linecap: round; }
.dialog .btn {
  display: flex; align-items: center; justify-content: center; gap: 10px; height: 52px; border-radius: 12px;
  background: var(--yellow); color: var(--ink); font-size: 16px; font-weight: 600;
}
.dialog .btn:hover { filter: brightness(0.96); }
.dialog .btn svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 2.2; stroke-linecap: round; stroke-linejoin: round; }
.dialog .btn svg.fill { fill: currentColor; stroke: none; }
.dialog .qr { margin: 24px auto 0; }
.dialog .qr img { width: 148px; height: 148px; margin: 0 auto 8px; border-radius: 10px; border: 8px solid #fff; }
.dialog .qr span, .dialog .hint { font-size: 13px; color: var(--muted); }
.dialog .hint { margin: 14px 0 0; }

/* WeChat's in-app browser blocks downloads */
.wechat-tip {
  position: fixed; inset: 0; z-index: 50; display: none;
  background: rgba(0, 0, 0, 0.8); color: #fff; text-align: right; padding: 16px 24px;
}
.wechat-tip.show { display: block; }
.wechat-tip .arrow { font-size: 44px; line-height: 1; color: var(--yellow); }
.wechat-tip p { margin: 10px 0 0; font-size: 18px; line-height: 1.7; }

/* ---------- Document pages (privacy, terms) ---------- */
main.doc { max-width: 760px; margin: 0 auto; padding: 48px 24px 80px; }
main.doc header { display: flex; align-items: center; gap: 12px; margin-bottom: 32px; }
main.doc header a { display: flex; align-items: center; }
main.doc .logo { width: 40px; height: 40px; border-radius: 10px; }
main.doc h1 { font-size: 28px; margin: 0; }
main.doc h2 { font-size: 20px; margin: 32px 0 8px; }
main.doc p, main.doc li { line-height: 1.75; }
main.doc a { text-decoration: underline; }
main.doc .muted { color: var(--muted); }
main.doc .card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 20px 24px; margin: 16px 0; }
main.doc footer { margin-top: 48px; font-size: 14px; color: var(--muted); }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .features { grid-template-columns: repeat(2, 1fr); }
  .more { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .hero { padding-bottom: 88px; border-bottom-left-radius: 50% 48px; border-bottom-right-radius: 50% 48px; }
  .hero-nav { justify-content: center; }
  .hero-brand { margin-top: 36px; gap: 12px; }
  .hero-brand img { width: 52px; height: 52px; border-radius: 13px; }
  .hero-brand span { font-size: 38px; }
  .hero-tagline { font-size: 17px; }
  .platforms { gap: 20px; margin-top: 40px; }
  .platform { width: 96px; height: 96px; }
  .features { grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 40px; padding: 0 16px; }
  .feature { padding: 26px 14px 22px; }
  .feature h3 { font-size: 16px; }
  .feature p { font-size: 13.5px; }
  .more { padding: 0 16px; gap: 12px; margin-top: 12px; }
  .dialog { padding: 40px 24px 28px; }
  .dialog .qr { display: none; }
}