:root { --ink: #1f2328; --sub: #57606a; --line: #d0d7de; --surface: #f6f8fa; --primary: #f2b705; }
* { box-sizing: border-box; }
body { margin: 0; font-family: "Noto Sans JP", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif; color: var(--ink); background: var(--surface); line-height: 1.8; }
header { background: #fff; border-bottom: 1px solid var(--line); }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 24px; }
header .wrap { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); font-weight: 700; }
.brand .mark { width: 32px; height: 32px; border-radius: 50%; background: var(--primary); color: var(--ink); display: inline-flex; align-items: center; justify-content: center; font-weight: 700; }
.brand small { font-weight: 400; color: var(--sub); margin-left: 4px; }
nav a { color: var(--ink); text-decoration: none; margin-left: 18px; font-size: 14px; }
nav a:hover { text-decoration: underline; }
main { padding: 40px 0 24px; }
article { background: #fff; border: 1px solid var(--line); border-radius: 8px; padding: 32px; }
h1 { font-size: 26px; margin: 0 0 4px; }
h2 { font-size: 18px; margin: 32px 0 8px; }
.meta { color: var(--sub); font-size: 13px; margin: 0 0 24px; }
p { margin: 0 0 12px; }
ul { padding-left: 24px; margin: 0 0 12px; }
footer { color: var(--sub); font-size: 12px; text-align: center; padding: 24px 0 40px; }
@media (max-width: 480px) { header .wrap { height: auto; padding: 12px 16px; flex-direction: column; align-items: flex-start; gap: 8px; } nav a { margin: 0 14px 0 0; } .wrap { padding: 0 16px; } article { padding: 20px; } }
.lead { font-size: 16px; margin: 0 0 8px; }
.cta { margin: 28px 0 0; }
.btn { display: inline-block; background: var(--primary); color: var(--ink); font-weight: 700; text-decoration: none; padding: 10px 20px; border-radius: 6px; }
.btn:hover { filter: brightness(0.95); }
.en { margin-top: 36px; padding-top: 4px; border-top: 1px solid var(--line); color: var(--sub); font-size: 14px; }
.en h2 { color: var(--ink); }
.tools { list-style: none; padding: 0; }
.tools li { border: 1px solid var(--line); border-radius: 8px; padding: 16px 20px; margin: 0 0 12px; }
.tools h3 { font-size: 17px; margin: 0 0 6px; }
.tools h3 a { color: var(--ink); }
.tools .links { margin: 0; font-size: 14px; }
.meta a { color: var(--sub); }