:root {
  color-scheme: dark;
  --bg: #0a0c0b;
  --surface: #111512;
  --surface-raised: #171c18;
  --line: #2a322c;
  --line-strong: #414d44;
  --text: #f4f7f4;
  --muted: #9ba79e;
  --lime: #b7ed20;
  --lime-dark: #23320b;
  --cyan: #65d6cd;
  --coral: #ff8f79;
  --max: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  letter-spacing: 0;
}
a { color: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
img { display: block; max-width: 100%; }
.skip-link {
  position: fixed;
  left: 16px;
  top: -60px;
  z-index: 20;
  padding: 10px 14px;
  background: var(--lime);
  color: #0b0d0b;
}
.skip-link:focus { top: 10px; }
.content-wrap { width: min(calc(100% - 40px), var(--max)); margin: 0 auto; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid var(--line);
  background: rgb(10 12 11 / 92%);
  backdrop-filter: blur(14px);
}
.header-inner {
  width: min(calc(100% - 40px), var(--max));
  min-height: 72px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  width: fit-content;
  color: var(--text);
  font-size: 19px;
  font-weight: 750;
  text-decoration: none;
}
.brand img { border-radius: 8px; }
.site-nav { display: flex; align-self: stretch; }
.site-nav a {
  display: flex;
  align-items: center;
  padding: 0 18px;
  border-bottom: 2px solid transparent;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}
.site-nav a:hover, .site-nav a.active { color: var(--text); }
.site-nav a.active { border-bottom-color: var(--lime); }
.language-switch {
  justify-self: end;
  display: inline-grid;
  grid-template-columns: 1fr 1fr;
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  overflow: hidden;
}
.language-switch button {
  min-width: 42px;
  min-height: 34px;
  border: 0;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  font-size: 12px;
  font-weight: 700;
}
.language-switch button[aria-pressed="true"] { background: var(--lime); color: #10130f; }

.page-intro { border-bottom: 1px solid var(--line); padding: 96px 0 72px; }
.intro-layout { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(320px, .75fr); gap: 80px; align-items: end; }
.eyebrow { margin: 0 0 14px; color: var(--lime); font-size: 12px; font-weight: 800; text-transform: uppercase; }
h1, h2, h3 { margin-top: 0; line-height: 1.2; letter-spacing: 0; }
h1 { max-width: 760px; margin-bottom: 22px; font-size: 56px; }
.lede { max-width: 720px; margin: 0; color: #c9d0cb; font-size: 19px; line-height: 1.8; }
.status-panel { border-top: 1px solid var(--line-strong); }
.status-panel div { display: grid; grid-template-columns: 1fr auto; gap: 20px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.status-panel strong { font-size: 14px; }
.status-panel span { color: var(--muted); font-size: 13px; text-align: right; }

.document-band { padding: 72px 0 96px; }
.document-layout { display: grid; grid-template-columns: 210px minmax(0, 760px); gap: 72px; justify-content: space-between; }
.document-index { position: sticky; top: 104px; align-self: start; display: grid; gap: 5px; }
.document-index p { margin: 0 0 12px; color: var(--muted); font-size: 11px; font-weight: 800; text-transform: uppercase; }
.document-index a { padding: 7px 0; color: var(--muted); font-size: 13px; text-decoration: none; }
.document-index a:hover { color: var(--lime); }
.document-meta { display: flex; gap: 12px; margin-bottom: 48px; color: var(--muted); font-size: 13px; }
.document-meta strong { color: var(--text); }
.document section { scroll-margin-top: 100px; margin-bottom: 64px; }
.document h2, .section-heading h2, .contact-layout h2 { margin-bottom: 22px; font-size: 30px; }
.document p { color: #c6cdc8; }
.note { padding: 16px 18px; border-left: 3px solid var(--cyan); background: #101b19; color: #bfe5df !important; }
.fact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; margin-top: 30px; border: 1px solid var(--line); background: var(--line); }
.fact-grid div { min-height: 128px; padding: 22px; background: var(--surface); }
.fact-grid strong, .fact-grid span { display: block; }
.fact-grid strong { margin-bottom: 10px; color: var(--lime); font-size: 14px; }
.fact-grid span { color: var(--muted); font-size: 13px; }
.permission-list { border-top: 1px solid var(--line-strong); }
.permission-list > div { display: grid; grid-template-columns: 150px 1fr; gap: 28px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.permission-list p { margin: 0; }
.check-list { margin: 0; padding: 0; list-style: none; }
.check-list li { position: relative; padding: 12px 0 12px 30px; border-bottom: 1px solid var(--line); color: #c6cdc8; }
.check-list li::before { content: "✓"; position: absolute; left: 0; color: var(--lime); font-weight: 800; }
.contact-strip { display: grid; grid-template-columns: 1fr auto; gap: 32px; align-items: center; padding: 32px; border: 1px solid var(--line-strong); background: var(--surface); }
.contact-strip h2 { margin-bottom: 8px; }
.contact-strip p { margin: 0; }
.primary-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid var(--lime);
  border-radius: 6px;
  background: var(--lime);
  color: #10130f;
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
}
.primary-link:hover { background: #c6f54a; }

.support-intro { padding-bottom: 80px; }
.mail-link { margin-top: 30px; }
.response-time { margin: 9px 0 0; color: var(--muted); font-size: 12px; }
.support-details { border: 1px solid var(--line-strong); background: var(--surface); }
.support-details div { display: flex; justify-content: space-between; gap: 20px; padding: 20px 22px; border-bottom: 1px solid var(--line); }
.support-details div:last-child { border-bottom: 0; }
.support-details span { color: var(--muted); font-size: 13px; }
.support-details strong { font-size: 14px; text-align: right; }
.quick-help-band { border-bottom: 1px solid var(--line); background: var(--surface); }
.quick-help { display: grid; grid-template-columns: repeat(4, 1fr); }
.quick-help a { min-height: 112px; padding: 24px; border-left: 1px solid var(--line); text-decoration: none; }
.quick-help a:last-child { border-right: 1px solid var(--line); }
.quick-help span, .quick-help strong { display: block; }
.quick-help span { margin-bottom: 16px; color: var(--cyan); font-size: 11px; font-weight: 800; }
.quick-help strong { font-size: 14px; }
.quick-help a:hover { background: var(--surface-raised); }
.support-content { padding: 80px 0 96px; }
.section-heading { margin-bottom: 52px; }
.faq-list { border-top: 1px solid var(--line-strong); }
.faq-group { scroll-margin-top: 100px; display: grid; grid-template-columns: 80px minmax(0, 1fr); gap: 36px; padding: 54px 0; border-bottom: 1px solid var(--line-strong); }
.faq-number { color: var(--cyan); font-size: 12px; font-weight: 800; }
.faq-group h3 { margin-bottom: 28px; font-size: 24px; }
details { border-top: 1px solid var(--line); }
details:last-child { border-bottom: 1px solid var(--line); }
summary { position: relative; padding: 18px 42px 18px 0; cursor: pointer; font-size: 15px; font-weight: 700; list-style: none; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: 8px; color: var(--lime); font-size: 20px; font-weight: 400; }
details[open] summary::after { content: "−"; }
details p { margin: 0; padding: 0 42px 20px 0; color: var(--muted); font-size: 14px; }
details a { color: var(--cyan); }
.contact-band { padding: 72px 0; border-top: 1px solid var(--line); background: #101411; }
.contact-layout { display: grid; grid-template-columns: 1fr auto; gap: 56px; align-items: center; }
.contact-layout p:not(.eyebrow) { max-width: 720px; margin-bottom: 0; color: var(--muted); }

.site-footer { padding: 30px 0; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.footer-inner { display: flex; justify-content: space-between; gap: 30px; align-items: center; }
.footer-inner div { display: flex; gap: 24px; }
.footer-inner a { text-decoration: none; }
.footer-inner a:hover { color: var(--text); }

@media (max-width: 820px) {
  .header-inner { grid-template-columns: 1fr auto; }
  .site-nav { grid-column: 1 / -1; grid-row: 2; min-height: 48px; justify-content: center; border-top: 1px solid var(--line); }
  .site-nav a { padding: 0 24px; }
  .page-intro { padding: 66px 0 56px; }
  .intro-layout { grid-template-columns: 1fr; gap: 48px; }
  h1 { font-size: 42px; }
  .document-layout { grid-template-columns: 1fr; gap: 0; }
  .document-index { display: none; }
  .fact-grid { grid-template-columns: 1fr; }
  .fact-grid div { min-height: auto; }
  .quick-help { grid-template-columns: repeat(2, 1fr); }
  .quick-help a:nth-child(3), .quick-help a:nth-child(4) { border-top: 1px solid var(--line); }
  .contact-strip, .contact-layout { grid-template-columns: 1fr; }
  .contact-strip .primary-link, .contact-layout .primary-link { width: 100%; }
}

@media (max-width: 520px) {
  .content-wrap, .header-inner { width: min(calc(100% - 28px), var(--max)); }
  .header-inner { gap: 12px; }
  .brand span { font-size: 17px; }
  .brand img { width: 34px; height: 34px; }
  h1 { font-size: 34px; }
  .lede { font-size: 17px; }
  .status-panel div { grid-template-columns: 1fr; gap: 3px; }
  .status-panel span { text-align: left; }
  .document-band, .support-content { padding: 54px 0 70px; }
  .document h2, .section-heading h2, .contact-layout h2 { font-size: 26px; }
  .permission-list > div { grid-template-columns: 1fr; gap: 6px; }
  .contact-strip { padding: 24px 18px; }
  .quick-help a { min-height: 102px; padding: 20px 16px; }
  .faq-group { grid-template-columns: 1fr; gap: 12px; padding: 42px 0; }
  .faq-number { font-size: 11px; }
  .footer-inner { align-items: flex-start; flex-direction: column; }
  .footer-inner div { flex-wrap: wrap; gap: 14px 20px; }
}