:root {
  color-scheme: light;
  --bg: #f4f6ef;
  --bg-soft: #e8eee3;
  --panel: #fbfcf8;
  --panel-strong: #e6f1e8;
  --text: #172620;
  --muted: #68766f;
  --muted-strong: #42524b;
  --line: rgba(23, 38, 32, 0.15);
  --line-strong: rgba(23, 38, 32, 0.24);
  --accent: #0c7b63;
  --accent-hover: #075541;
  --accent-ink: #ffffff;
  --accent-text: #0c7b63;
  --accent-soft: rgba(12, 123, 99, 0.12);
  --accent-line: rgba(12, 123, 99, 0.42);
  --max: 1240px;
  --nav-height: 72px;
  --radius: 8px;
}

@font-face {
  font-family: "OPPO Sans";
  src: local("OPPO Sans"), local("OPPOSans"), url("/assets/oppo-sans-4.0.ttf?v=20260829") format("truetype");
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
}

* { box-sizing: border-box; }
html { background: var(--bg); scroll-behavior: smooth; overflow-x: clip; }
body {
  margin: 0;
  min-width: 320px;
  overflow-x: clip;
  background: var(--bg);
  color: var(--text);
  font-family: "OPPO Sans", Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  letter-spacing: 0;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button { font: inherit; }
p, h1, h2, h3, blockquote { overflow-wrap: anywhere; }
h1, h2, h3, p, blockquote { margin-top: 0; }
h1, h2, h3 { line-height: 1.12; letter-spacing: 0; }
.site-shell { min-height: 100vh; overflow: clip; }
.section-pad, .site-nav, .site-footer {
  width: min(100% - 48px, var(--max));
  margin-inline: auto;
}

.site-nav {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  height: var(--nav-height);
  display: grid;
  grid-template-columns: minmax(205px, 1fr) auto minmax(205px, 1fr);
  align-items: center;
  padding: 0 18px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: background-color 180ms ease, border-color 180ms ease;
}
.site-nav.is-scrolled, .site-nav.is-open {
  background: rgba(244, 246, 239, 0.9);
  border-color: var(--line);
  box-shadow: 0 10px 40px rgba(23, 38, 32, 0.08);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
}
.wordmark { display: inline-flex; align-items: center; gap: 10px; font-size: 17px; font-weight: 760; white-space: nowrap; }
.brand-logo { width: 34px; height: 34px; flex: 0 0 34px; object-fit: cover; border-radius: 10px; }
.wordmark span { color: var(--text); font-size: 17px; font-weight: 760; }
.site-nav nav { display: flex; align-items: center; gap: 30px; }
.site-nav nav a { color: var(--muted-strong); font-size: 14px; transition: color 150ms ease; }
.site-nav nav a:hover, .site-nav nav a.active { color: var(--text); }
.nav-action {
  justify-self: end;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 0 17px;
  border-radius: 6px;
  background: var(--accent);
  color: var(--accent-ink);
  font-size: 14px;
  font-weight: 700;
}
.nav-menu {
  display: none;
  width: 42px;
  height: 42px;
  padding: 11px 9px;
  border: 0;
  background: transparent;
  color: var(--text);
}
.nav-menu span { display: block; height: 1px; margin: 6px 0; background: currentColor; transition: transform 160ms ease; }
.site-nav.is-open .nav-menu span:first-child { transform: translateY(3.5px) rotate(45deg); }
.site-nav.is-open .nav-menu span:last-child { transform: translateY(-3.5px) rotate(-45deg); }

.eyebrow {
  margin-bottom: 18px;
  color: var(--accent-text);
  font-size: 12px;
  font-weight: 720;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.lead { max-width: 720px; color: var(--muted-strong); font-size: 20px; }
.hero {
  min-height: min(880px, 100svh);
  padding-top: 150px;
  padding-bottom: 72px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(380px, .95fr);
  align-items: center;
  gap: 72px;
  border-bottom: 1px solid var(--line);
}
.hero h1 { max-width: 760px; margin-bottom: 28px; font-size: clamp(60px, 7vw, 106px); font-weight: 760; }
.hero-title-line { display: inline-block; white-space: nowrap; }
.hero-lede { max-width: 610px; margin-bottom: 36px; color: var(--muted-strong); font-size: 21px; }
.button-row { display: flex; flex-wrap: wrap; gap: 12px; }
.button {
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  transition: transform 150ms ease, border-color 150ms ease;
}
.button:hover { transform: translateY(-2px); border-color: rgba(23,38,32,.25); }
.button-primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.nav-action:hover, .button-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.button-ghost { background: rgba(255,255,255,.55); }
.operator-line { margin-top: 30px; color: var(--muted); font-size: 13px; }
.scale-signal { position: relative; aspect-ratio: 1; width: min(100%, 560px); justify-self: end; }
.scale-signal i {
  position: absolute;
  inset: 50% auto auto 50%;
  width: var(--size);
  height: var(--size);
  transform: translate(-50%, -50%) rotate(45deg);
  border: 1px solid rgba(10, 128, 103, var(--alpha));
  border-radius: 50% 50% 50% 8%;
  animation: signal 12s ease-in-out infinite alternate;
}
.scale-signal i:nth-child(1) { --size: 22%; --alpha: .62; }
.scale-signal i:nth-child(2) { --size: 42%; --alpha: .42; animation-delay: -2s; }
.scale-signal i:nth-child(3) { --size: 64%; --alpha: .26; animation-delay: -4s; }
.scale-signal i:nth-child(4) { --size: 88%; --alpha: .14; animation-delay: -6s; }
.scale-signal::after { content: ""; position: absolute; inset: 6%; border: 1px solid var(--line); border-radius: 50%; }
.scale-signal span { position: absolute; left: 50%; bottom: 4%; transform: translateX(-50%); color: var(--muted); font-size: 12px; white-space: nowrap; }
@keyframes signal { to { transform: translate(-50%, -50%) rotate(51deg) scale(1.035); } }

.loop { padding-top: 120px; padding-bottom: 130px; }
.loop > h2, .plain-band h2 { max-width: 860px; margin-bottom: 56px; font-size: clamp(38px, 5vw, 68px); }
.loop-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.loop-grid article { min-height: 250px; padding: 32px 26px; border-right: 1px solid var(--line); }
.loop-grid article:last-child { border-right: 0; }
.loop-grid b { display: flex; width: 42px; height: 42px; align-items: center; justify-content: center; margin-bottom: 56px; border: 1px solid var(--accent-line); border-radius: 50%; color: var(--accent-text); font-size: 13px; }
.loop-grid h3 { margin-bottom: 9px; font-size: 22px; }
.loop-grid p { margin-bottom: 0; color: var(--muted); }

.product-feature, .detail-section {
  min-height: 820px;
  padding-top: 110px;
  padding-bottom: 110px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(340px, 520px);
  align-items: center;
  gap: 100px;
  border-top: 1px solid var(--line);
}
.product-feature-reverse, .detail-reverse { grid-template-columns: minmax(340px, 520px) minmax(0, 1fr); }
.feature-copy h2, .detail-copy h2 { max-width: 710px; margin-bottom: 24px; font-size: clamp(38px, 4.5vw, 66px); }
.feature-copy > p:not(.eyebrow), .detail-copy > p:not(.eyebrow) { max-width: 650px; color: var(--muted-strong); font-size: 19px; }
.text-link { display: inline-flex; gap: 10px; align-items: center; margin-top: 20px; color: var(--accent-text); font-weight: 700; }
.text-link span { transition: transform 150ms ease; }
.text-link:hover span { transform: translateX(4px); }
.phone-frame {
  width: min(100%, 390px);
  justify-self: center;
  padding: 10px;
  border: 1px solid rgba(255,255,255,.19);
  border-radius: 38px;
  background: var(--panel-strong);
  box-shadow: 0 34px 100px rgba(0,0,0,.42);
}
.phone-frame img { width: 100%; border-radius: 29px; }
.story-tease { min-height: 620px; padding-top: 140px; padding-bottom: 120px; display: flex; flex-direction: column; justify-content: center; border-top: 1px solid var(--line); }
.channel-entry { padding-top: 120px; padding-bottom: 120px; border-top: 1px solid var(--line); }
.channel-entry .section-heading { margin-bottom: 52px; }
.channel-entry .section-heading h2 { max-width: 860px; margin-bottom: 18px; font-size: clamp(36px, 4vw, 58px); }
.channel-entry .section-heading p { max-width: 720px; color: var(--muted); font-size: 18px; }
.channel-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1px; border: 1px solid var(--line); background: var(--line); }
.channel-grid article { min-height: 320px; padding: 32px; background: var(--bg-soft); }
.channel-index { color: var(--accent-text); font-size: 12px; }
.channel-grid h3 { margin: 74px 0 16px; font-size: 28px; }
.channel-grid p { min-height: 78px; color: var(--muted); }
.download-route { margin-top: 110px; padding-top: 90px; border-top: 1px solid var(--line); }
.download-route h2 { max-width: 760px; margin-bottom: 20px; font-size: clamp(34px, 4vw, 56px); }
.download-route p:not(.eyebrow) { max-width: 720px; color: var(--muted-strong); font-size: 18px; }
.story-tease blockquote { max-width: 1100px; margin-bottom: 34px; font-family: "OPPO Sans", "PingFang SC", "Microsoft YaHei", sans-serif; font-size: clamp(48px, 7vw, 98px); font-style: normal; font-weight: 700; line-height: 1.18; letter-spacing: 0; }
.trust-strip { padding-top: 110px; padding-bottom: 120px; display: grid; grid-template-columns: 1.4fr .6fr; gap: 72px; border-top: 1px solid var(--line); }
.trust-strip h2 { max-width: 720px; font-size: clamp(36px, 4vw, 58px); }
.trust-lede { max-width: 760px; color: var(--muted-strong); font-size: 18px; }
.trust-numbers { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 1px; margin: 34px 0 10px; background: var(--line); border: 1px solid var(--line); }
.trust-numbers div { padding: 24px 20px; background: var(--bg); }
.trust-numbers strong { display: block; color: var(--accent-text); font-size: 40px; line-height: 1; }
.trust-numbers span { display: block; margin-top: 10px; color: var(--muted); font-size: 12px; }
.chips { display: flex; flex-wrap: wrap; gap: 10px; margin: 36px 0 10px; }
.chips span { padding: 8px 12px; border: 1px solid var(--line); border-radius: 5px; color: var(--muted-strong); font-size: 13px; }
.content-placeholder { align-self: end; padding: 28px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); }
.content-placeholder p:not(.eyebrow) { margin-bottom: 5px; }
.content-placeholder small { color: var(--muted); }
.species-preview { align-self: end; padding: 30px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); }
.species-preview > div { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 22px; }
.species-preview span { padding: 7px 10px; border: 1px solid var(--line); border-radius: 4px; color: var(--muted-strong); font-size: 13px; }
.species-preview small { color: var(--muted); }

.page-hero, .download-page, .partners-page, .sources-page, .about-page, .legal-page { padding-top: 180px; padding-bottom: 130px; }
.page-hero { min-height: 650px; display: flex; flex-direction: column; justify-content: center; }
.page-hero h1, .download-page > h1, .partners-page > h1, .sources-page > h1, .about-page > h1, .legal-page > h1 { max-width: 980px; margin-bottom: 28px; font-size: clamp(52px, 7vw, 96px); }
.detail-section { min-height: 760px; }
.plain-band { padding-top: 130px; padding-bottom: 140px; border-top: 1px solid var(--line); }
.plain-band p:last-child { max-width: 720px; color: var(--muted); font-size: 20px; }

.download-page, .partners-page, .sources-page, .about-page, .legal-page { min-height: calc(100vh - 220px); }
.download-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: stretch; margin-top: 70px; }
.download-mark, .download-panel { min-height: 540px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); }
.download-mark { display: grid; place-items: center; overflow: hidden; }
.download-mark img { width: min(70%, 420px); border-radius: 14%; }
.download-panel { padding: 46px; display: flex; flex-direction: column; justify-content: center; }
.qr-placeholder, .qr-live { width: min(100%, 280px); display: grid; place-content: center; gap: 8px; margin: 0 auto 20px; text-align: center; }
.qr-placeholder { aspect-ratio: 1; border: 1px dashed var(--accent-line); color: var(--accent-text); }
.qr-placeholder small, .qr-live small { color: var(--muted); }
.qr-live img { width: 258px; max-width: 100%; border: 1px solid var(--line); }
.availability-note { padding: 13px; border-radius: 5px; background: var(--accent); color: var(--accent-ink); font-weight: 700; text-align: center; }
.platform-list { margin-top: 24px; border-top: 1px solid var(--line); }
.platform-list div { display: flex; justify-content: space-between; padding: 15px 2px; border-bottom: 1px solid var(--line); }
.platform-list em { color: var(--muted); font-style: normal; }

.partner-grid, .source-grid, .legal-grid { display: grid; gap: 1px; margin-top: 70px; background: var(--line); border: 1px solid var(--line); }
.partner-grid, .source-grid { grid-template-columns: repeat(3, minmax(0,1fr)); }
.legal-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
.partner-grid article, .source-grid article, .legal-grid section { min-height: 310px; padding: 36px; background: var(--bg-soft); }
.partner-grid span, .source-index { color: var(--accent-text); font-size: 13px; }
.partner-grid h2, .source-grid h2, .legal-grid h2 { margin-top: 70px; margin-bottom: 18px; font-size: 26px; }
.partner-grid p, .source-grid p, .legal-grid p { color: var(--muted-strong); }
.partner-grid small, .source-grid small { color: var(--muted); }
.partner-principles, .contact-placeholder, .source-note, .operator-proof { margin-top: 70px; padding: 44px; border: 1px solid var(--line); border-radius: var(--radius); }
.partner-principles > div { display: grid; grid-template-columns: repeat(4,1fr); gap: 1px; background: var(--line); }
.partner-principles b { padding: 24px; background: var(--bg); text-align: center; }
.contact-placeholder h2, .operator-proof h2 { max-width: 860px; font-size: clamp(30px, 4vw, 48px); }
.source-note p:last-child, .operator-proof p:last-child { color: var(--muted); }

.business-wechat { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: 48px; align-items: center; }
.business-wechat h2 { margin: 16px 0 18px; }
.business-wechat p:last-child { max-width: 520px; color: var(--muted); }
.business-wechat-qr { aspect-ratio: 1; display: grid; place-items: center; overflow: hidden; border: 1px solid var(--line-strong); background: var(--bg-soft); }
.business-wechat-qr img { width: 100%; height: 100%; object-fit: contain; }
.business-wechat-qr-live { aspect-ratio: auto; padding: 12px 12px 0; }
.business-wechat-qr-live img { height: auto; }
.business-wechat-qr span { display: grid; gap: 8px; color: var(--accent-text); font-size: 15px; text-align: center; }
.business-wechat-qr small { color: var(--muted); font-size: 12px; font-weight: 400; }
.business-wechat-qr > small { padding: 0 0 14px; }

.sources-page { width: min(100% - 48px, var(--max)); }
.sources-hero { min-height: 720px; display: flex; flex-direction: column; justify-content: center; padding-bottom: 90px; }
.sources-hero h1 { max-width: 1050px; }
.source-stats { display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); margin-top: 64px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.source-stats div { padding: 30px 24px; border-right: 1px solid var(--line); }
.source-stats div:last-child { border-right: 0; }
.source-stats strong { display: block; color: var(--accent-text); font-size: 58px; line-height: 1; }
.source-stats span { display: block; margin-top: 12px; color: var(--muted); font-size: 13px; }
.source-principles { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.source-principles article { min-height: 360px; padding: 38px 32px; border-right: 1px solid var(--line); }
.source-principles article:last-child { border-right: 0; }
.source-principles span { color: var(--accent-text); font-size: 13px; }
.source-principles h2 { margin-top: 100px; font-size: 30px; }
.source-principles p { color: var(--muted); }
.institution-section, .source-directory, .coverage-section { padding: 130px 0; border-bottom: 1px solid var(--line); }
.section-heading { display: grid; grid-template-columns: minmax(180px,.36fr) minmax(0,1fr); gap: 40px; align-items: start; margin-bottom: 64px; }
.section-heading .eyebrow { margin-top: 8px; }
.section-heading h2 { max-width: 850px; margin-bottom: 0; font-size: clamp(38px,5vw,66px); }
.section-heading > p:last-child { color: var(--muted); font-size: 18px; }
.institution-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 1px; border: 1px solid var(--line); background: var(--line); }
.institution-grid article { min-height: 310px; padding: 36px; background: var(--bg-soft); }
.institution-grid b, .directory-groups b { color: var(--accent-text); font-size: 12px; }
.institution-grid h3 { max-width: 470px; margin: 66px 0 16px; font-size: 27px; }
.institution-grid p { max-width: 540px; color: var(--muted); }
.directory-groups { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 24px; }
.directory-groups article { padding: 32px; border: 1px solid var(--line); border-radius: var(--radius); }
.directory-groups h3 { margin-bottom: 28px; font-size: 22px; }
.directory-groups ul { margin: 0; padding: 0; list-style: none; }
.directory-groups li { padding: 15px 0; border-top: 1px solid var(--line); color: var(--muted-strong); }
.directory-groups li b { display: inline-block; min-width: 52px; }
.category-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 1px; border: 1px solid var(--line); background: var(--line); }
.category-grid article { min-height: 170px; padding: 28px; background: var(--bg-soft); }
.category-grid span { color: var(--text); font-size: 20px; font-weight: 700; }
.category-grid p { margin-top: 28px; margin-bottom: 0; color: var(--muted); font-size: 14px; }
.coverage-note { max-width: 840px; margin: 32px 0 0 auto; color: var(--muted); font-size: 13px; }
.review-route { display: grid; grid-template-columns: 1fr 80px 1fr 80px 1fr; align-items: center; padding: 90px 0 20px; }
.review-route div { display: flex; align-items: center; gap: 14px; }
.review-route span { display: grid; place-items: center; width: 42px; height: 42px; border: 1px solid var(--accent-line); border-radius: 50%; color: var(--accent-text); font-size: 12px; }
.review-route i { height: 1px; background: var(--line-strong); }

.about-page { max-width: 1040px; }
.letter { max-width: 780px; margin-top: 78px; margin-left: auto; font-size: 19px; line-height: 1.95; }
.letter p { margin-bottom: 32px; color: var(--muted-strong); }
.letter .letter-emphasis { padding: 32px 0 32px 28px; border-left: 2px solid var(--accent); color: var(--text); }
.letter .letter-break { margin-top: 70px; color: var(--accent-text); font-size: 30px; font-weight: 700; line-height: 1.35; }
.operator-proof { max-width: 900px; margin-top: 120px; margin-left: auto; }
.legal-grid a { color: var(--accent-text); }

.site-footer { min-height: 210px; padding: 58px 0; display: grid; grid-template-columns: 1fr 1fr; gap: 42px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }
.site-footer > div:last-child { justify-self: end; text-align: right; }
.site-footer .wordmark { color: var(--text); }
.site-footer a:hover { color: var(--text); }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px 18px; }
.footer-links a { color: var(--accent-text); }
.footer-registration { display: flex; margin-top: 10px; flex-wrap: wrap; align-items: center; justify-content: flex-end; gap: 8px 16px; }
.footer-registration a { color: inherit; line-height: 20px; }
.footer-police-registration { display: inline-flex; align-items: center; gap: 6px; white-space: nowrap; }
.footer-police-registration img { display: block; width: 18px; height: 20px; flex: 0 0 auto; object-fit: contain; }

.reveal-ready [data-reveal] { opacity: 0; transform: translateY(24px); transition: opacity 650ms ease, transform 650ms ease; }
.reveal-ready [data-reveal].is-visible { opacity: 1; transform: none; }

@media (max-width: 980px) {
  :root { --nav-height: 62px; }
  .section-pad, .site-footer { width: min(100% - 32px, var(--max)); }
  .site-nav { top: 10px; width: min(calc(100% - 40px), var(--max)); grid-template-columns: 1fr auto; padding: 0 12px 0 18px; }
  .site-nav .nav-action { display: none; }
  .nav-menu { display: block; justify-self: end; }
  .site-nav nav { position: fixed; z-index: -1; inset: -10px calc((100vw - 100%)/-2) auto; width: 100vw; height: 100vh; display: none; padding: 112px 32px 32px; flex-direction: column; align-items: stretch; gap: 18px; border: 0; border-radius: 0; background: var(--bg); }
  .site-nav.is-open nav { display: flex; }
  .site-nav nav a { padding: 0; color: var(--text); font-size: 26px; font-weight: 700; }
  .hero { min-height: auto; padding-top: 150px; grid-template-columns: 1fr; gap: 40px; }
  .scale-signal { width: min(90vw, 500px); justify-self: center; }
  .loop-grid { grid-template-columns: repeat(2,1fr); }
  .loop-grid article:nth-child(2) { border-right: 0; }
  .loop-grid article:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .product-feature, .detail-section, .product-feature-reverse, .detail-reverse { grid-template-columns: 1fr; min-height: auto; gap: 58px; }
  .product-feature-reverse .phone-frame, .detail-reverse .phone-frame { order: 2; }
  .trust-strip { grid-template-columns: 1fr; }
  .channel-grid { grid-template-columns: 1fr; }
  .channel-grid article { min-height: 260px; }
  .source-stats { grid-template-columns: repeat(2,1fr); }
  .source-stats div:nth-child(2) { border-right: 0; }
  .source-stats div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .source-principles { grid-template-columns: 1fr; }
  .source-principles article { min-height: 260px; border-right: 0; border-bottom: 1px solid var(--line); }
  .source-principles article:last-child { border-bottom: 0; }
  .source-principles h2 { margin-top: 58px; }
  .directory-groups { grid-template-columns: 1fr; }
  .category-grid { grid-template-columns: repeat(2,1fr); }
  .review-route { grid-template-columns: 1fr; gap: 18px; }
  .review-route i { width: 1px; height: 28px; margin-left: 21px; }
  .download-grid { grid-template-columns: 1fr; }
  .partner-grid, .source-grid { grid-template-columns: 1fr; }
  .partner-grid article, .source-grid article { min-height: 260px; }
}

@media (max-width: 640px) {
  .section-pad, .site-footer { width: min(100% - 24px, var(--max)); }
  .hero { padding-top: 125px; padding-bottom: 56px; }
  .hero h1 { font-size: clamp(40px, 12.5vw, 52px); }
  .hero-lede, .lead { font-size: 17px; }
  .scale-signal { width: 94%; }
  .loop { padding-top: 80px; padding-bottom: 90px; }
  .loop > h2 { margin-bottom: 36px; }
  .loop-grid { grid-template-columns: 1fr; }
  .loop-grid article { min-height: 180px; border-right: 0; border-bottom: 1px solid var(--line); }
  .loop-grid article:last-child { border-bottom: 0; }
  .loop-grid b { margin-bottom: 30px; }
  .product-feature, .detail-section { padding-top: 80px; padding-bottom: 84px; gap: 44px; }
  .phone-frame { width: min(84vw, 350px); border-radius: 32px; }
  .phone-frame img { border-radius: 24px; }
  .story-tease { min-height: 480px; padding-top: 90px; padding-bottom: 80px; }
  .channel-entry { padding-top: 84px; padding-bottom: 88px; }
  .channel-entry .section-heading { margin-bottom: 38px; }
  .channel-grid h3 { margin-top: 46px; }
  .channel-grid p { min-height: 0; }
  .download-route { margin-top: 80px; padding-top: 68px; }
  .trust-strip { padding-top: 80px; padding-bottom: 90px; }
  .trust-numbers { grid-template-columns: 1fr; }
  .trust-numbers div { border-bottom: 1px solid var(--line); }
  .trust-numbers div:last-child { border-bottom: 0; }
  .page-hero, .download-page, .partners-page, .sources-page, .about-page, .legal-page { padding-top: 130px; padding-bottom: 90px; }
  .page-hero { min-height: 540px; }
  .page-hero h1, .download-page > h1, .partners-page > h1, .sources-page > h1, .about-page > h1, .legal-page > h1 { font-size: 50px; }
  .download-grid, .partner-grid, .source-grid, .legal-grid { margin-top: 50px; }
  .download-mark, .download-panel { min-height: 400px; }
  .download-panel, .partner-grid article, .source-grid article, .legal-grid section { padding: 26px; }
  .partner-grid h2, .source-grid h2, .legal-grid h2 { margin-top: 44px; }
  .legal-grid { grid-template-columns: 1fr; }
  .partner-principles, .contact-placeholder, .source-note, .operator-proof { padding: 28px; }
  .business-wechat { grid-template-columns: 1fr; }
  .business-wechat-qr { width: min(100%, 240px); }
  .partner-principles > div { grid-template-columns: repeat(2,1fr); }
  .sources-page { width: min(100% - 24px, var(--max)); }
  .sources-hero { min-height: 620px; padding-bottom: 68px; }
  .source-stats strong { font-size: 46px; }
  .source-stats div { padding: 24px 18px; }
  .institution-section, .source-directory, .coverage-section { padding: 86px 0; }
  .section-heading { grid-template-columns: 1fr; gap: 12px; margin-bottom: 40px; }
  .institution-grid, .category-grid { grid-template-columns: 1fr; }
  .institution-grid article { min-height: 270px; padding: 26px; }
  .institution-grid h3 { margin-top: 48px; }
  .category-grid article { min-height: 145px; }
  .letter { margin-top: 54px; font-size: 17px; line-height: 1.9; }
  .letter .letter-emphasis { padding-left: 20px; }
  .site-footer { grid-template-columns: 1fr; }
  .site-footer > div:last-child { justify-self: start; text-align: left; }
  .footer-registration { justify-content: flex-start; }
  .footer-links { justify-content: flex-start; }

  /* Allow long Chinese headlines to wrap naturally on narrow screens. */
  .page-hero h1 br,
  .ecosystem-page > h1 br,
  .partners-page > h1 br,
  .sources-hero h1 br,
  .section-heading h2 br,
  .species-directory-hero h1 br { display: none; }
  .page-hero h1,
  .ecosystem-page > h1,
  .partners-page > h1,
  .sources-hero h1,
  .section-heading h2,
  .species-directory-hero h1 { text-wrap: pretty; }
  .ecosystem-page > h1 { font-size: 44px; }
  .partners-page > h1 { font-size: 40px; }
  .detail-copy h2 { font-size: 32px; }
  .plain-band h2 { font-size: 32px; }
  .coverage-section .section-heading h2 { font-size: 34px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}

/* Multi-platform ecosystem system */
.platform-matrix, .ecosystem-panel { border-top: 1px solid var(--line); }
.platform-matrix { margin-top: 26px; padding: 34px; border-radius: var(--radius); background: var(--panel); }
.platform-matrix h2 { max-width: 880px; margin: 6px 0 12px; font-size: clamp(32px, 4vw, 52px); }
.platform-intro { margin: 0; color: var(--muted); font-size: 16px; }
.platform-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-top: 34px; }
.platform-grid article { min-height: 112px; padding: 17px; border: 1px solid var(--line); border-radius: 6px; background: var(--bg); }
.platform-grid article.platform-coral { border-color: rgba(239, 111, 86, .55); }
.platform-label { display: block; color: var(--accent-text); font-size: 11px; font-weight: 700; }
.platform-coral .platform-label, .ecosystem-hero-grid .platform-coral .platform-label { color: #ef806c; }
.platform-grid h3 { margin: 7px 0 4px; font-size: 15px; }
.platform-grid p { margin: 0; color: var(--muted); font-size: 11px; }
.product-proof-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; align-self: center; }
.proof-screen { overflow: hidden; padding: 10px 10px 0; border: 1px solid var(--line); border-radius: 18px; background: var(--panel); }
.proof-screen > span { display: block; width: fit-content; padding: 6px 13px; border-radius: 12px; background: var(--accent); color: var(--accent-ink); font-size: 11px; font-weight: 700; }
.proof-screen.coral > span { background: #ef6f56; color: #24120e; }
.proof-screen.pale > span { background: #c9f2de; color: #10251e; }
.proof-screen img { width: 100%; margin-top: 10px; border-radius: 10px 10px 0 0; }
.ecosystem-panel { margin-top: 24px; padding: 34px; border-radius: var(--radius); background: var(--panel); }
.ecosystem-panel .section-heading { margin-bottom: 30px; }
.ecosystem-panel .section-heading h2 { font-size: clamp(32px, 4vw, 52px); }
.ecosystem-grid, .ecosystem-hero-grid, .principle-grid, .future-platforms { display: grid; gap: 12px; }
.ecosystem-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.ecosystem-grid article, .ecosystem-hero-grid article { min-height: 158px; padding: 20px; border: 1px solid var(--line); border-radius: 6px; background: var(--bg); }
.ecosystem-grid article > span, .ecosystem-hero-grid article > span { color: var(--accent-text); font-size: 11px; font-weight: 700; }
.ecosystem-grid h3 { margin: 24px 0 8px; font-size: 25px; }
.ecosystem-grid p, .ecosystem-grid small { color: var(--muted); }
.ecosystem-grid p { margin-bottom: 6px; }
.ecosystem-page { padding-top: 180px; padding-bottom: 120px; }
.ecosystem-page > h1 { max-width: 900px; margin-bottom: 24px; font-size: clamp(54px, 7vw, 96px); }
.ecosystem-page > .lead { max-width: 760px; }
.ecosystem-hero-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); margin-top: 78px; }
.ecosystem-hero-grid article { min-height: 330px; padding: 30px; }
.ecosystem-hero-grid h2 { margin: 92px 0 14px; font-size: 36px; }
.ecosystem-hero-grid p { max-width: 320px; color: var(--muted-strong); }
.ecosystem-hero-grid small { color: var(--muted); }
.ecosystem-principles, .ecosystem-future { padding-top: 112px; border-top: 1px solid var(--line); margin-top: 112px; }
.principle-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); margin-top: 32px; }
.principle-grid article { padding: 28px; border: 1px solid var(--line); border-radius: 6px; background: var(--panel); }
.principle-grid strong { font-size: 22px; }
.principle-grid p { margin: 18px 0 0; color: var(--muted); }
.ecosystem-future h2 { max-width: 800px; margin: 10px 0 34px; font-size: clamp(36px, 5vw, 66px); }
.future-platforms { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.future-platforms div { display: flex; min-height: 80px; flex-direction: column; justify-content: space-between; padding: 18px; border: 1px solid var(--line); border-radius: 6px; background: var(--panel); }
.future-platforms strong { font-size: 20px; }
.future-platforms span { color: var(--muted); font-size: 12px; }

@media (max-width: 980px) {
  .platform-grid, .future-platforms { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .product-proof-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .ecosystem-hero-grid { grid-template-columns: 1fr; }
  .ecosystem-hero-grid article { min-height: 240px; }
  .ecosystem-hero-grid h2 { margin-top: 48px; }
  .principle-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .platform-matrix, .ecosystem-panel { padding: 24px; }
  .platform-grid, .ecosystem-grid, .product-proof-grid, .future-platforms { grid-template-columns: 1fr; }
  .platform-grid article { min-height: 96px; }
  .proof-screen { max-width: 250px; margin-inline: auto; }
  .ecosystem-page { padding-top: 130px; padding-bottom: 88px; }
  .ecosystem-page > h1 { font-size: 44px; }
  .ecosystem-hero-grid { margin-top: 52px; }
  .ecosystem-principles, .ecosystem-future { margin-top: 80px; padding-top: 80px; }
}