:root {
  color-scheme: dark;
  --bg: #281233;
  --panel: rgba(58, 25, 70, .72);
  --panel-solid: #32163e;
  --pink: #ff2d8a;
  --pink-soft: #ff83bd;
  --cyan: #53e8e2;
  --gold: #f0c14b;
  --text: #fff7fb;
  --muted: #bba6b6;
  --line: rgba(255, 69, 151, .32);
  --shadow: 0 24px 70px rgba(0, 0, 0, .55);
  --sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", Arial, sans-serif;
  --display: Georgia, "Times New Roman", "Noto Serif SC", serif;
}

* { box-sizing: border-box; letter-spacing: 0; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  min-height: 100%;
  margin: 0;
  overflow-x: hidden;
  color: var(--text);
  background-color: var(--bg);
  background-image: url("/invite-assets/landing-bg.webp");
  background-position: center top;
  background-size: cover;
  background-repeat: repeat-y;
  background-attachment: fixed;
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: none;
}
a { color: inherit; text-decoration: none; }
button, input, select { font: inherit; }
button { color: inherit; }
img { display: block; max-width: 100%; }

.button {
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 15px;
  font-weight: 800;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, filter .18s ease;
}
.button:hover { transform: translateY(-2px); }
.button:active { transform: translateY(0) scale(.98); }
.button.primary {
  background: linear-gradient(120deg, #ff5aa5, #d4146a 52%, #ff2d8a);
  box-shadow: 0 12px 30px rgba(212, 20, 106, .44), inset 0 1px rgba(255, 255, 255, .35);
}
.button.primary:hover { filter: brightness(1.08); box-shadow: 0 16px 36px rgba(212, 20, 106, .55); }
.button.ghost { border-color: rgba(255, 255, 255, .34); background: rgba(112, 54, 115, .26); backdrop-filter: blur(12px); }
.button.large { min-height: 54px; padding: 0 28px; font-size: 16px; }
.button.compact { min-height: 38px; padding: 0 16px; font-size: 13px; }

.age-gate {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 16px;
  background: rgba(64, 24, 77, .78);
  backdrop-filter: blur(14px);
  transition: opacity .3s ease, visibility .3s ease;
}
.age-gate::before { content: ""; position: absolute; inset: 0; background: linear-gradient(135deg, rgba(217, 49, 132, .24), rgba(94, 54, 160, .18)), url("/invite-assets/landing-bg.webp") center / cover no-repeat; opacity: .68; }
.age-gate.hidden { opacity: 0; visibility: hidden; pointer-events: none; }
.age-card {
  position: relative;
  width: min(400px, 100%);
  padding: 34px 28px 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(67, 29, 79, .88);
  box-shadow: var(--shadow), 0 0 38px rgba(255, 45, 138, .38);
  text-align: center;
}
.age-badge {
  width: 72px;
  height: 72px;
  margin: 0 auto 16px;
  border: 2px solid rgba(240, 193, 75, .7);
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: linear-gradient(145deg, #ff6bb5, #c4106a 58%, #4a0a28);
  box-shadow: 0 0 28px rgba(255, 45, 138, .54);
  font-size: 22px;
  font-weight: 900;
}
.age-card h2 { margin: 0 0 8px; font-size: 23px; }
.age-card p { margin: 0 0 22px; color: var(--muted); font-size: 13px; line-height: 1.75; }
.age-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  width: min(1120px, calc(100% - 32px));
  height: 72px;
  margin: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(255, 255, 255, .12);
  background: linear-gradient(180deg, rgba(61, 25, 74, .9), rgba(67, 29, 79, .52) 72%, transparent);
  backdrop-filter: blur(16px);
}
.brand { display: flex; align-items: center; gap: 8px; }
.brand b { font-family: var(--display); font-size: 25px; color: #fff; }
.brand span { color: var(--pink-soft); font-size: 22px; }
.brand small { padding: 3px 7px; border: 1px solid rgba(240, 193, 75, .58); border-radius: 999px; color: var(--gold); font-size: 10px; }

main, footer { width: min(1120px, calc(100% - 32px)); margin: auto; }
main#top { scroll-margin-top: 72px; }
.hero {
  position: relative;
  min-height: 700px;
  padding: 48px 0 54px;
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  align-items: center;
  gap: 28px;
  isolation: isolate;
}
.hero-backdrop { position: absolute; inset: 20px -5vw; z-index: -1; background: rgba(93, 43, 101, .06); }
.hero-copy { position: relative; z-index: 2; }
.kicker { margin: 0 0 14px; color: var(--cyan); font-size: 11px; font-weight: 800; }
.kicker span { display: inline-block; width: 24px; height: 1px; margin-right: 8px; vertical-align: middle; background: linear-gradient(90deg, var(--cyan), transparent); box-shadow: 0 0 10px var(--cyan); }
.hero h1 { margin: 0; font-family: var(--display); font-size: 70px; line-height: 1.02; font-weight: 800; }
.hero h1 em, .join-intro h2 em { font-style: normal; color: transparent; background: linear-gradient(90deg, #ffb5d6, #ff2d8a 52%, #ff83bd); background-clip: text; -webkit-background-clip: text; filter: drop-shadow(0 0 18px rgba(255, 45, 138, .38)); }
.lead { max-width: 430px; margin: 18px 0; color: #f1d1df; font-size: 15px; line-height: 1.8; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 25px; }
.chips span { padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; background: rgba(255, 45, 138, .13); color: #ffd0e4; font-size: 12px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.platform-note { max-width: 520px; margin: 12px 0 0; color: var(--muted); font-size: 12px; line-height: 1.65; }
.invite-note { margin: 16px 0 0; color: var(--muted); font-size: 12px; }
.install-attribution-card {
  width: min(820px, 100%);
  margin: 8px auto 24px;
  padding: 24px;
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  border: 1px solid rgba(255, 105, 182, .58);
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(111, 47, 112, .9), rgba(49, 23, 65, .92));
  box-shadow: 0 20px 55px rgba(65, 24, 72, .38), inset 0 1px rgba(255,255,255,.13);
  scroll-margin-top: 84px;
}
.install-attribution-icon {
  width: 64px;
  height: 64px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255, 117, 188, .76);
  border-radius: 18px;
  color: #fff;
  background: linear-gradient(145deg, #ff5da9, #bd176b 58%, #61103d);
  box-shadow: 0 0 28px rgba(255, 45, 138, .42);
  font-family: var(--display);
  font-size: 30px;
  font-weight: 900;
}
.install-attribution-copy h2 { margin: 2px 0 8px; font-size: 25px; }
.install-attribution-copy > p:not(.kicker):not(.status) { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.7; }
.install-attribution-actions { margin-top: 16px; display: flex; flex-wrap: wrap; gap: 10px; }
.install-attribution-fallback { margin-top: 12px !important; color: #ffd3e5 !important; }
.install-attribution-card .status { margin: 8px 0 0; text-align: left; }
.hero-poster {
  position: relative;
  width: min(100%, 440px);
  height: auto;
  justify-self: end;
  overflow: visible;
  border: 1px solid rgba(255, 93, 176, .68);
  border-radius: 8px;
  box-shadow: 0 32px 80px rgba(71, 25, 72, .4), 0 0 46px rgba(255, 45, 138, .3);
  background: rgba(111, 49, 112, .28);
}
.hero-poster img { width: 100%; height: auto; object-fit: contain; object-position: center top; }
.hero-poster::after { content: none; }
.poster-pulse { position: absolute; left: 22px; bottom: 28px; z-index: 2; height: 38px; display: flex; align-items: center; gap: 6px; }
.poster-pulse::before, .poster-pulse::after { content: ""; width: 46px; height: 2px; background: var(--pink); box-shadow: 0 0 14px var(--pink); }
.poster-pulse i { width: 3px; height: 10px; background: var(--pink); transform: skew(-18deg); box-shadow: 0 0 12px var(--pink); }
.poster-pulse i:nth-child(3) { height: 34px; }

.section { padding: 82px 0; }
.section-title { margin-bottom: 30px; }
.section-title h2, .join-intro h2 { margin: 0 0 8px; font-family: var(--display); font-size: 44px; line-height: 1.08; }
.section-title > p:last-child, .join-intro > p { margin: 0; color: var(--muted); line-height: 1.75; }
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.feature {
  min-height: 258px;
  padding: 24px;
  border-top: 2px solid rgba(255, 69, 151, .65);
  background: linear-gradient(145deg, rgba(101, 45, 108, .7), rgba(58, 27, 75, .72));
  box-shadow: inset 0 1px rgba(255, 255, 255, .12), 0 18px 42px rgba(66, 26, 78, .24);
}
.feature-icon { position: relative; width: 52px; height: 52px; margin-bottom: 32px; display: block; border: 1px solid rgba(255, 85, 174, .52); border-radius: 8px; background: rgba(255, 45, 138, .08); box-shadow: inset 0 0 18px rgba(255, 45, 138, .1); }
.feature-en { margin: 0; color: var(--pink-soft); font-size: 9px; font-weight: 800; }
.feature h3 { margin: 7px 0 10px; font-size: 24px; }
.feature > p:last-child { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.7; }
.icon-book::before { content: ""; position: absolute; inset: 14px 9px 10px; border: 2px solid var(--pink-soft); border-radius: 3px; }
.icon-book::after { content: ""; position: absolute; left: 25px; top: 14px; width: 2px; height: 28px; background: var(--pink-soft); }
.icon-photo::before { content: ""; position: absolute; inset: 15px 9px 11px; border: 2px solid var(--pink-soft); border-radius: 3px; }
.icon-photo::after { content: ""; position: absolute; left: 20px; top: 21px; width: 10px; height: 10px; border: 2px solid var(--pink-soft); border-radius: 50%; }
.icon-play::before { content: ""; position: absolute; left: 21px; top: 16px; border-left: 17px solid var(--pink-soft); border-top: 11px solid transparent; border-bottom: 11px solid transparent; }
.icon-people::before, .icon-people::after { content: ""; position: absolute; width: 12px; height: 12px; top: 13px; border: 2px solid var(--pink-soft); border-radius: 50%; }
.icon-people::before { left: 10px; box-shadow: 20px 0 0 -2px var(--panel-solid), 20px 0 0 0 var(--pink-soft); }
.icon-people::after { left: 8px; top: 31px; width: 34px; height: 10px; border-radius: 12px 12px 0 0; border-bottom: 0; }

.preview-section { padding-top: 68px; }
.preview-viewport { overflow: hidden; padding: 8px 0 16px; mask-image: linear-gradient(90deg, transparent, #000 4%, #000 96%, transparent); }
.preview-track { width: max-content; display: flex; gap: 12px; animation: preview-marquee 28s linear infinite; }
.preview-track img { width: 192px; height: 270px; flex: 0 0 auto; object-fit: cover; border: 1px solid rgba(255, 105, 187, .52); border-bottom: 3px solid var(--pink); border-radius: 10px; background: rgba(77, 34, 89, .65); box-shadow: 0 12px 30px rgba(72, 23, 79, .38); }
.preview-viewport:hover .preview-track { animation-play-state: paused; }
@keyframes preview-marquee { to { transform: translateX(calc(-50% - 6px)); } }

.join {
  margin: 72px 0;
  padding: 52px;
  display: grid;
  grid-template-columns: .82fr 1.18fr;
  gap: 52px;
  align-items: start;
  border-block: 1px solid var(--line);
  background: linear-gradient(90deg, rgba(111, 50, 112, .32), rgba(88, 38, 99, .56), rgba(111, 50, 112, .32));
}
.join-intro { position: sticky; top: 96px; }
.join-intro h2 { font-size: 52px; }
.join-steps { margin-top: 28px; display: grid; gap: 10px; }
.join-steps span { display: flex; align-items: center; gap: 12px; color: #d1bfce; }
.join-steps b { width: 34px; height: 34px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 50%; color: var(--pink-soft); font-size: 11px; }
.register-card, .success-card { padding: 30px; border: 1px solid rgba(255, 105, 182, .54); border-radius: 8px; background: linear-gradient(145deg, rgba(114, 47, 112, .86), rgba(63, 30, 82, .86)); box-shadow: 0 24px 65px rgba(65, 24, 72, .34), inset 0 1px rgba(255,255,255,.14); }
.register-card { scroll-margin-top: 88px; }
.register-card header h2, .success-card h2 { margin: 4px 0; font-size: 28px; }
.register-card header > p:last-child, .success-card p { color: var(--muted); }
.register-card form { margin-top: 22px; display: grid; gap: 14px; }
.field-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
label { display: grid; gap: 7px; color: #e4d5e3; font-size: 12px; }
input, select { width: 100%; height: 50px; padding: 0 14px; border: 1px solid rgba(204, 116, 187, .54); border-radius: 6px; outline: 0; background: rgba(71, 31, 84, .8); color: #fff; font-size: 14px; }
input:focus, select:focus { border-color: var(--pink-soft); box-shadow: 0 0 0 3px rgba(255, 45, 138, .12); }
input::placeholder { color: #746878; }
.locked-invite { border-style: dashed; color: #f4e0ef; background: linear-gradient(135deg, rgba(105, 45, 101, .78), rgba(69, 32, 86, .76)); cursor: not-allowed; }
.security-protection { overflow: hidden; border: 1px solid rgba(204, 116, 187, .5); border-radius: 6px; background: rgba(255,255,255,.1); }
.security-protection summary { padding: 14px; display: flex; align-items: center; justify-content: space-between; list-style: none; cursor: pointer; }
.security-protection summary::-webkit-details-marker { display: none; }
.security-protection summary span { display: grid; gap: 4px; }
.security-protection summary small, .security-protection-body p { color: var(--muted); font-size: 11px; }
.security-protection summary b { color: var(--pink-soft); font-size: 12px; }
.security-protection[open] summary b { font-size: 0; }
.security-protection[open] summary b::after { content: "收起"; font-size: 12px; }
.security-protection-body { padding: 0 14px 14px; display: grid; gap: 12px; border-top: 1px solid rgba(255,255,255,.08); }
.captcha-row { display: grid; grid-template-columns: minmax(0, 1fr) minmax(132px, 160px) auto; gap: 10px; align-items: end; }
.captcha-preview { height: 50px; overflow: hidden; border: 1px solid rgba(135, 70, 124, .6); border-radius: 6px; background: #ffe9f1; }
.captcha-preview img { width: 100%; height: 100%; object-fit: cover; }
.captcha-refresh { width: 42px; height: 42px; padding: 0; border: 1px solid rgba(255, 105, 182, .64); border-radius: 50%; display: grid; place-items: center; background: rgba(255, 45, 138, .18); color: var(--pink-soft); cursor: pointer; box-shadow: 0 0 16px rgba(255, 45, 138, .2); transition: transform .18s ease, background .18s ease; }
.captcha-refresh:hover { transform: rotate(90deg); background: rgba(255, 45, 138, .3); }
.captcha-refresh span { font-size: 24px; line-height: 1; }
.submit { width: 100%; margin-top: 4px; }
.status { min-height: 20px; margin: 0; text-align: center; color: var(--pink-soft); font-size: 13px; }
.success-card { width: min(900px, 100%); margin: 0 auto 80px; display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); align-items: center; gap: 32px; }
.success-icon { width: 62px; height: 62px; margin-bottom: 16px; display: grid; place-items: center; border-radius: 50%; background: linear-gradient(145deg, var(--pink), #9c3ed5); box-shadow: 0 0 30px rgba(255, 45, 138, .48); font-size: 30px; }
.success-card .button { width: 100%; margin-top: 10px; }
.download-options { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.download-option { min-width: 0; padding: 16px; border: 1px solid rgba(255, 105, 182, .42); border-radius: 8px; background: rgba(47, 21, 61, .54); box-shadow: inset 0 1px rgba(255,255,255,.08); }
.download-option-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; margin-bottom: 12px; }
.download-option-heading b { color: #fff; font-size: 16px; }
.download-option-heading span { color: var(--muted); font-size: 11px; }
.download-qr { text-align: center; }
.qr-frame { padding: 12px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.qr-frame img { width: 100%; }
.qr-frame.is-placeholder { background: rgba(255,255,255,.94); }
.download-qr span { color: var(--muted); font-size: 11px; }
.download-link { width: 100%; min-height: 42px; margin-top: 12px; padding-inline: 8px; font-size: 12px; }
.download-link.is-disabled { opacity: .48; filter: saturate(.35); cursor: not-allowed; pointer-events: auto; }
.ios-install-mark { position: relative; min-height: 154px; display: grid; place-items: center; overflow: hidden; border: 1px solid rgba(83, 232, 226, .24); border-radius: 8px; background: radial-gradient(circle at 50% 38%, rgba(83,232,226,.2), transparent 48%), rgba(10, 45, 58, .5); }
.ios-install-mark span { color: #eaffff; font-family: Arial, sans-serif; font-size: 72px; line-height: 1; text-shadow: 0 0 24px rgba(83,232,226,.64); }
.ios-install-mark i { position: absolute; width: 46px; height: 46px; border: 1px solid rgba(83,232,226,.62); border-radius: 50%; box-shadow: 0 0 22px rgba(83,232,226,.4); }
.download-unavailable { min-height: 32px; margin: 10px 0 0; color: var(--muted); font-size: 11px; line-height: 1.5; text-align: center; }

footer { padding: 28px 0 max(38px, env(safe-area-inset-bottom)); display: flex; align-items: center; gap: 20px; border-top: 1px solid rgba(255,255,255,.12); color: var(--muted); font-size: 11px; }
.footer-brand { margin-right: auto; color: var(--pink-soft); font-family: var(--display); font-size: 22px; font-weight: 800; }

@media (max-width: 900px) {
  .hero { min-height: 660px; grid-template-columns: 1fr .9fr; }
  .hero h1 { font-size: 58px; }
  .hero-poster { height: 500px; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .join { grid-template-columns: 1fr; padding: 38px; }
  .join-intro { position: static; }
  .join-steps { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 700px) {
  body { background-size: auto 760px; background-attachment: scroll; }
  .topbar, main, footer { width: min(100% - 28px, 560px); }
  .topbar { height: 66px; }
  main#top { scroll-margin-top: 66px; }
  .hero { min-height: 0; padding: 24px 0 34px; display: flex; flex-direction: column; align-items: stretch; gap: 22px; }
  .hero-backdrop { inset: 0 -14px; background: rgba(91, 40, 98, .04); }
  .hero h1 { font-size: 50px; }
  .lead { font-size: 14px; }
  .hero-poster { width: min(100%, 360px); height: auto; justify-self: center; align-self: center; }
  .install-attribution-card { grid-template-columns: 48px minmax(0, 1fr); padding: 18px 14px; gap: 12px; }
  .install-attribution-icon { width: 48px; height: 48px; border-radius: 14px; font-size: 24px; }
  .install-attribution-copy h2 { font-size: 21px; }
  .install-attribution-actions { display: grid; }
  .install-attribution-actions .button { width: 100%; }
  .section { padding: 64px 0; }
  .section-title h2 { font-size: 38px; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .feature { min-height: 220px; padding: 18px; }
  .feature-icon { margin-bottom: 20px; }
  .feature h3 { font-size: 20px; }
  .preview-track img { width: 172px; height: 242px; }
  .join { margin: 50px -14px; padding: 28px 14px; gap: 32px; }
  .join-intro h2 { font-size: 42px; }
  .join-steps { grid-template-columns: 1fr; }
  .register-card { padding: 22px 16px; }
  .field-pair { grid-template-columns: 1fr; }
  .captcha-row { grid-template-columns: minmax(0, 1fr) minmax(110px, 132px) auto; }
  .success-card { grid-template-columns: 1fr; padding: 24px 18px; text-align: center; }
  .success-icon { margin-inline: auto; }
  .download-options { grid-template-columns: 1fr; }
  .download-option { width: min(260px, 100%); margin: auto; }
  .download-qr { width: 210px; margin: auto; }
  footer { flex-wrap: wrap; }
  footer p { margin-left: auto; }
  footer span { width: 100%; text-align: center; }
}

@media (max-width: 390px) {
  .hero { min-height: 0; }
  .hero h1 { font-size: 44px; }
  .hero-actions { display: grid; }
  .hero-actions .button { width: 100%; }
  .hero-poster { width: min(100%, 335px); height: auto; }
  .feature-grid { grid-template-columns: 1fr; }
  .captcha-row { grid-template-columns: minmax(0, 1fr) minmax(98px, 118px) auto; }
}

@media (prefers-reduced-motion: reduce) {
  .preview-track { animation: none; }
}