:root {
  color-scheme: dark;
  font-family: Inter, "Microsoft YaHei UI", "PingFang SC", sans-serif;
  background: #07101f;
  color: rgba(243, 247, 255, .94);
}
* { box-sizing: border-box; }
body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 70% 12%, rgba(75, 125, 194, .2), transparent 34%),
    linear-gradient(145deg, #0c1729, #050b15 72%);
}
a { color: inherit; }
.install-shell {
  width: min(720px, calc(100% - 32px));
  margin: 0 auto;
  padding: 64px 0 52px;
}
.install-header { text-align: center; }
.install-header img { border-radius: 18px; box-shadow: 0 16px 40px rgba(0, 0, 0, .28); }
.install-header > p:first-of-type { margin: 14px 0 28px; color: rgba(195, 213, 238, .64); font-size: .78rem; letter-spacing: .12em; }
.install-header h1 { margin: 0; font-size: clamp(2rem, 7vw, 3.25rem); font-weight: 540; letter-spacing: -.04em; }
.install-lead { max-width: 32rem; margin: 16px auto 0; color: rgba(203, 217, 238, .72); line-height: 1.75; }
.install-note {
  display: grid;
  gap: 5px;
  margin: 38px 0 18px;
  padding: 16px 18px;
  border: 1px solid rgba(135, 184, 246, .2);
  border-radius: 14px;
  background: rgba(98, 157, 232, .09);
  color: rgba(218, 232, 252, .8);
  font-size: .86rem;
  line-height: 1.6;
}
.install-note strong { color: rgba(246, 249, 255, .94); }
.install-steps { display: grid; gap: 12px; margin: 0; padding: 0; list-style: none; }
.install-step {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 16px;
  padding: 22px;
  border: 1px solid rgba(215, 230, 250, .1);
  border-radius: 18px;
  background: rgba(229, 238, 252, .045);
}
.install-step__number {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border-radius: 50%;
  background: rgba(119, 175, 245, .15);
  color: rgba(212, 231, 255, .9);
  font-variant-numeric: tabular-nums;
}
.install-step h2 { margin: 4px 0 7px; font-size: 1rem; font-weight: 560; }
.install-step p { margin: 0; color: rgba(199, 214, 236, .68); font-size: .86rem; line-height: 1.7; }
.install-step code { padding: 3px 6px; border-radius: 6px; background: rgba(2, 7, 15, .42); color: rgba(223, 236, 255, .9); }
.primary-action {
  display: inline-flex;
  min-height: 46px;
  margin-top: 16px;
  padding: 0 18px;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(172, 208, 255, .28);
  border-radius: 12px;
  background: rgba(103, 164, 239, .24);
  color: #f4f8ff;
  font-size: .88rem;
  text-decoration: none;
  transition: background 180ms ease, border-color 180ms ease;
}
.primary-action:hover,
.primary-action:focus-visible { border-color: rgba(182, 216, 255, .46); outline: 2px solid rgba(157, 200, 255, .3); background: rgba(113, 176, 251, .34); }
.install-footer { padding: 28px 8px 0; text-align: center; }
.install-footer p { margin: 0 auto 14px; color: rgba(187, 203, 226, .62); font-size: .78rem; line-height: 1.7; }
.install-footer a { color: rgba(198, 222, 252, .82); font-size: .82rem; }
@media (max-width: 520px) {
  .install-shell { width: min(100% - 24px, 720px); padding-top: 36px; }
  .install-step { grid-template-columns: 40px minmax(0, 1fr); gap: 12px; padding: 18px 15px; }
  .install-step__number { width: 40px; height: 40px; }
  .primary-action { width: 100%; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: .01ms !important; }
}