:root {
  color-scheme: light;
  --ink: #1c2942;
  --muted: #7888a0;
  --line: rgba(220, 226, 237, 0.9);
  --accent: #6366f1;
  --accent-deep: #4f46e5;
  --card: rgba(255, 255, 255, 0.84);
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  overflow-x: hidden;
  color: var(--ink);
  background: #f8fafc;
  font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  -webkit-font-smoothing: antialiased;
}

body::before,
body::after {
  position: fixed;
  z-index: -1;
  display: block;
  content: "";
  width: 360px;
  height: 360px;
  border-radius: 50%;
  pointer-events: none;
  filter: blur(108px);
}

body::before {
  top: 6vh;
  left: 20vw;
  background: rgba(139, 92, 246, 0.23);
}

body::after {
  right: 18vw;
  bottom: 6vh;
  background: rgba(56, 189, 248, 0.2);
}

button,
a {
  font: inherit;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
a.entry-button,
a.support-account-link {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 3px solid rgba(99, 102, 241, 0.42);
  outline-offset: 3px;
}

.page-shell {
  display: grid;
  min-height: 100vh;
  place-items: center;
  padding: 40px 20px;
}

.download-card {
  width: min(100%, 480px);
  padding: 34px 30px 23px;
  border: 1px solid rgba(255, 255, 255, 0.92);
  border-radius: 20px;
  background: var(--card);
  box-shadow: 0 24px 58px rgba(15, 23, 42, 0.16), 0 0 1px rgba(15, 23, 42, 0.1) inset;
  backdrop-filter: blur(16px);
}

.brand-header {
  display: flex;
  align-items: center;
  justify-content: center;
}

h1,
h2,
p {
  margin: 0;
}

h1 {
  color: var(--ink);
  font-size: 23px;
  font-weight: 800;
  letter-spacing: -0.045em;
}

.divider {
  height: 1px;
  margin: 21px 0 17px;
  background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.22), transparent);
}

.intro-copy {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.72;
  text-align: center;
}

.entry-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 21px;
}

.entry-button {
  display: flex;
  min-height: 55px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  padding: 9px 8px;
  border: 1px solid rgba(203, 213, 225, 0.88);
  border-radius: 11px;
  background: rgba(255, 255, 255, 0.7);
  color: #334155;
  font-size: 12.5px;
  font-weight: 650;
  line-height: 1.25;
  text-align: center;
  transition: border-color 180ms ease, background-color 180ms ease, box-shadow 180ms ease, color 180ms ease, transform 180ms ease;
}

.entry-button:hover {
  border-color: rgba(99, 102, 241, 0.66);
  background: #fff;
  color: var(--accent-deep);
  box-shadow: 0 8px 20px rgba(99, 102, 241, 0.14);
  transform: translateY(-2px);
}

.entry-button:active {
  transform: translateY(0);
}

.site-footer {
  margin-top: 20px;
  padding-top: 15px;
  border-top: 1px solid rgba(226, 232, 240, 0.82);
  color: #9aa7b9;
  font-size: 10.5px;
  line-height: 1.7;
  text-align: center;
}

.support-launcher {
  position: fixed;
  right: 24px;
  bottom: 24px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 42px;
  padding: 0 17px;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 999px;
  background: linear-gradient(135deg, #6366f1, #a855f7);
  box-shadow: 0 10px 28px rgba(99, 102, 241, 0.32);
  color: white;
  cursor: pointer;
  font-size: 13px;
  font-weight: 700;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.support-launcher:hover {
  box-shadow: 0 14px 32px rgba(99, 102, 241, 0.4);
  transform: translateY(-2px);
}

.support-icon {
  font-size: 15px;
}

.support-backdrop {
  position: fixed;
  inset: 0;
  z-index: 5;
  display: grid;
  place-items: end;
  padding: 24px;
  background: rgba(15, 23, 42, 0.28);
  opacity: 0;
  pointer-events: none;
  transition: opacity 180ms ease;
}

.support-backdrop.is-open {
  opacity: 1;
  pointer-events: auto;
}

.support-panel {
  width: min(100%, 360px);
  padding: 22px;
  border: 1px solid rgba(255, 255, 255, 0.75);
  border-radius: 17px;
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 22px 55px rgba(15, 23, 42, 0.2);
  transform: translateY(10px);
  transition: transform 180ms ease;
}

.support-backdrop.is-open .support-panel {
  transform: translateY(0);
}

.support-panel-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
}

.support-eyebrow {
  color: #8b5cf6;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.support-panel h2 {
  margin-top: 5px;
  font-size: 18px;
  letter-spacing: -0.03em;
}

.support-close {
  width: 30px;
  height: 30px;
  border: 0;
  border-radius: 50%;
  background: #f1f5f9;
  color: #64748b;
  cursor: pointer;
  font-size: 23px;
  line-height: 1;
}

.support-copy {
  margin-top: 19px;
  color: #64748b;
  font-size: 13px;
  line-height: 1.7;
}

.support-account-link {
  display: inline-flex;
  margin-top: 18px;
  color: var(--accent-deep);
  font-size: 13px;
  font-weight: 750;
}

.support-account-link:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (max-width: 560px) {
  .page-shell {
    padding: 24px 14px 84px;
  }

  .download-card {
    padding: 29px 19px 20px;
    border-radius: 17px;
  }

  h1 {
    font-size: 21px;
  }

  .entry-grid {
    gap: 8px;
  }

  .entry-button {
    min-height: 58px;
    padding-inline: 5px;
    font-size: 11.5px;
  }

  .support-launcher {
    right: 15px;
    bottom: 15px;
    padding-inline: 15px;
  }

  .support-backdrop {
    padding: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}