:root {
  color-scheme: light;
  --green-900: #123b2a;
  --green-700: #176b49;
  --green-600: #16865a;
  --green-100: #e9f5ef;
  --ink: #17211c;
  --muted: #5e6c64;
  --line: #dfe8e3;
  --surface: #ffffff;
  --canvas: #f4f8f6;
  font-family: "Segoe UI", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 88% 8%, rgba(22, 134, 90, 0.12), transparent 30rem),
    var(--canvas);
}

.page-shell {
  width: min(980px, calc(100% - 32px));
  margin: 0 auto;
  padding: 64px 0 40px;
}

.hero {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 28px;
  padding: 44px;
  color: #fff;
  background: linear-gradient(135deg, var(--green-900), var(--green-700));
  border-radius: 24px;
  box-shadow: 0 22px 54px rgba(18, 59, 42, 0.18);
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 76px;
  height: 76px;
  font-size: 34px;
  font-weight: 700;
  color: var(--green-900);
  background: #fff;
  border-radius: 20px;
}

.eyebrow {
  margin: 0 0 8px;
  color: #bfe6d2;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

h1 {
  margin: 0;
  font-size: clamp(34px, 5vw, 52px);
  line-height: 1.15;
}

.summary {
  max-width: 640px;
  margin: 18px 0;
  color: #e5f2ec;
  font-size: 18px;
  line-height: 1.75;
}

.release-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}

.release-row span {
  padding: 7px 11px;
  color: #dcece4;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 999px;
  font-size: 13px;
}

.release-row .version {
  color: var(--green-900);
  background: #d8f0e3;
  border-color: transparent;
  font-weight: 700;
}

.primary-action {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 24px;
  color: var(--green-900);
  background: #fff;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
  transition: transform 140ms ease, box-shadow 140ms ease;
}

.primary-action:hover,
.primary-action:focus-visible {
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.18);
}

.action-note {
  margin: 14px 0 0;
  color: #cfe5d9;
  font-size: 13px;
}

.card {
  margin-top: 22px;
  padding: 32px 36px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
}

h2 {
  margin: 0 0 22px;
  color: var(--green-900);
  font-size: 22px;
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: install-step;
}

.steps li {
  position: relative;
  min-height: 168px;
  padding: 54px 18px 18px;
  background: #f7faf8;
  border: 1px solid var(--line);
  border-radius: 14px;
  counter-increment: install-step;
}

.steps li::before {
  position: absolute;
  top: 16px;
  left: 18px;
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  color: #fff;
  background: var(--green-600);
  border-radius: 9px;
  content: counter(install-step);
  font-weight: 700;
}

.steps strong,
.steps span { display: block; }

.steps span {
  margin-top: 9px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.65;
}

.notes ul {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
  line-height: 1.9;
}

footer {
  padding: 26px 12px 0;
  color: var(--muted);
  text-align: center;
  font-size: 14px;
}

footer p { margin: 5px 0; }
.privacy { color: #7b8881; font-size: 13px; }

@media (max-width: 780px) {
  .page-shell { padding-top: 24px; }
  .hero { grid-template-columns: 1fr; padding: 30px 24px; }
  .steps { grid-template-columns: 1fr 1fr; }
  .steps li { min-height: 150px; }
}

@media (max-width: 520px) {
  .page-shell { width: min(100% - 20px, 980px); }
  .hero { border-radius: 18px; }
  .card { padding: 26px 22px; }
  .steps { grid-template-columns: 1fr; }
  .steps li { min-height: 0; }
  .primary-action { width: 100%; }
}