:root {
  color-scheme: light dark;
  --bg: #f4f7f5; --paper: #fff; --ink: #172720; --muted: #4c6259;
  --line: #d2ded8; --accent: #086454; --on-accent: #fff;
  font: 100%/1.65 -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  background: var(--bg); color: var(--ink);
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #111815; --paper: #19231e; --ink: #f2f7f4; --muted: #b1c5b9;
    --line: #384b3e; --accent: #91e5ce; --on-accent: #0e3027; }
}
* { box-sizing: border-box; }
body { margin: 0; overflow-wrap: break-word; word-break: keep-all; }
main { max-width: 51rem; margin: 0 auto; padding: 0 max(1.25rem, env(safe-area-inset-right)) max(3rem, env(safe-area-inset-bottom)) max(1.25rem, env(safe-area-inset-left)); }
header { padding: max(2rem, env(safe-area-inset-top)) 0 1.5rem; }
.brand { display: inline-flex; min-height: 44px; align-items: center; }
.brand img { display: block; }
h1, h2, h3, p { margin: 0; }
h1 { margin-top: 1.75rem; font-size: clamp(2.5rem, 7vw, 4rem); line-height: 1.12; letter-spacing: -.055em; }
section { padding: clamp(1.25rem, 4vw, 2.25rem); background: var(--paper); border: 1px solid var(--line); border-radius: 1.25rem; }
section + section { margin-top: 1rem; }
.platform { display: flex; align-items: baseline; gap: .65rem; }
h2 { color: var(--accent); font-size: 1.1rem; }
.platform span, .hint, .version { color: var(--muted); }
.platform span { font-size: .875rem; }
h3 { margin: .35rem 0; font-size: clamp(1.5rem, 5vw, 2rem); line-height: 1.35; letter-spacing: -.045em; }
.version { font-size: .95rem; }
.action { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: .6rem 1.3rem; border-radius: .65rem; font-weight: 700; text-decoration: none; }
.primary { margin-top: 1.15rem; color: var(--on-accent); background: var(--accent); }
.secondary { border: 1px solid var(--line); }
a { color: var(--accent); text-underline-offset: .17em; }
a:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
.action:hover { text-decoration: underline; }
.hint { margin-top: 1rem; max-width: 57ch; font-size: .95rem; }
ol { margin: 1rem 0 1.25rem; padding-inline-start: 1.65rem; }
li { padding-inline-start: .3rem; }
li + li { margin-top: .55rem; }
li::marker { font-weight: 700; color: var(--accent); }
@media (max-width: 30rem) { .action { width: 100%; } }