:root { --bg: #f4f1e9; --ink: #0b3c2c; --muted: #4c665b; --accent: #e9650d; --card: #ffffff; --line: #d9d4c7; }
@media (prefers-color-scheme: dark) { :root { --bg: #092a20; --ink: #f4f1e9; --muted: #b9cbc2; --accent: #ff914a; --card: #10392c; --line: #1f4a3b; } }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.8 -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif; }
main { max-width: 760px; margin: 0 auto; padding: 40px 20px 72px; }
header { display: flex; align-items: center; gap: 12px; margin-bottom: 28px; }
header img { width: 44px; height: 44px; border-radius: 10px; }
.wordmark { font: 800 20px/1 Arial, sans-serif; letter-spacing: 1.5px; }
.wordmark em { font-style: normal; color: var(--accent); }
h1 { font-size: 28px; line-height: 1.4; margin: 0 0 6px; }
h2 { font-size: 19px; margin: 34px 0 8px; }
p, li { color: var(--ink); }
.muted { color: var(--muted); font-size: 14px; }
section.card { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 18px 20px; margin: 16px 0; }
a { color: var(--accent); }
nav.lang { margin-top: 40px; font-size: 14px; }
dt { font-weight: 700; margin-top: 14px; }
dd { margin: 4px 0 0; }
section.card h2.first { margin-top: 0; }