:root {
  color-scheme: light dark;
  --background: #fff; --surface: #f3f3f3; --text: #202020;
  --muted: #5d6369; --accent: #0069b9; --line: #e1e4e8;
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Arial, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    --background: #181818; --surface: #252526; --text: #e9e9e9;
    --muted: #a6a6a6; --accent: #0078d4; --line: #333;
  }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--background); color: var(--text); font-size: 16px; line-height: 1.6; }
a { color: inherit; text-underline-offset: .25em; }
a:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
.skip { position: absolute; top: -90px; left: 20px; background: var(--surface); padding: 12px; }
.skip:focus { top: 8px; }
.shell { max-width: 1120px; padding: 0 48px; margin: auto; }
header { min-height: 88px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { text-decoration: none; font-weight: 650; font-size: 20px; letter-spacing: -.5px; }
nav { display: flex; gap: 28px; font-size: 14px; }
nav a { text-decoration: none; color: var(--muted); }
nav a[aria-current] { color: var(--text); }
nav a:hover { color: var(--accent); }
main { text-align: center; }
h1, p { margin-top: 0; }
h1 { font-size: clamp(40px, 5vw, 68px); font-weight: 550; line-height: 1.12; letter-spacing: -2px; margin-bottom: 26px; }
.intro { font-size: 20px; line-height: 1.6; color: var(--muted); max-width: 610px; margin: 0 auto 24px; }
.primary { display: inline-block; border: 0; padding: 11px 20px; background: var(--accent); color: #fff; border-radius: 4px; text-decoration: none; font: 600 15px/1.6 "Segoe UI", -apple-system, BlinkMacSystemFont, Arial, sans-serif; }
a.primary:hover { filter: brightness(.9); }
.home { min-height: calc(100vh - 88px); padding: 112px 0; display: flex; flex-direction: column; align-items: center; justify-content: center; }
.hardware { font: 13px/1.6 ui-monospace, "SFMono-Regular", Consolas, monospace; color: var(--muted); margin: 0 0 38px; }
.product { min-height: calc(100vh - 88px); padding: 84px 0; display: grid; justify-items: center; align-content: center; }
.product h1 { font-size: clamp(64px, 8vw, 92px); margin-bottom: 12px; }
.product .intro { margin-bottom: 12px; }
.privacy { color: var(--muted); margin-bottom: 28px; }
.purchase { margin-top: 12px; }
.price { font-size: 40px; font-weight: 550; line-height: 1.2; letter-spacing: -1px; margin: 0 0 20px; }
.price span { font: 12px/1 ui-monospace, "SFMono-Regular", Consolas, monospace; letter-spacing: 0; color: var(--muted); }
.purchase > p:not(.price) { color: var(--muted); font-size: 14px; margin-bottom: 22px; }
.primary:disabled { cursor: default; }
@media (max-width: 900px) {
  .shell { padding: 0 32px; }
  header { min-height: 76px; }
  h1 { font-size: 48px; }
  .intro { font-size: 18px; }
  .home { padding: 80px 0; }
}
@media (max-width: 640px) {
  .shell { padding: 0 24px; }
  header { min-height: 70px; gap: 20px; }
  nav { gap: 18px; font-size: 13px; }
  .brand { font-size: 18px; }
  h1 { font-size: 38px; letter-spacing: -1.5px; }
  .home { min-height: calc(100vh - 70px); padding: 70px 0; }
  .intro { font-size: 17px; }
  .hardware { font-size: 12px; }
  .product { min-height: auto; padding: 42px 0; }
  .product h1 { font-size: 60px; }
}

.buyer-help { max-width: 760px; margin: auto; padding: 56px 0; text-align: left; }
.buyer-help h1 { font-size: 38px; letter-spacing: -1px; }
.buyer-help h2 { font-size: 20px; font-weight: 600; margin: 28px 0 8px; }
.buyer-help p { color: var(--muted); margin-bottom: 12px; }