:root{--ink:#24231f;--paper:#f7f5ef;--white:#fffefa;--muted:#6d6a61;--line:#d8d3c7;--accent:#b8742f;--accent-dark:#7d481d;--soft:#ece7dc;--serif:"Yu Mincho","Hiragino Mincho ProN","Noto Serif JP",serif;--sans:-apple-system,BlinkMacSystemFont,"Hiragino Kaku Gothic ProN","Yu Gothic","Noto Sans JP",sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:var(--paper);font:16px/1.9 var(--sans);-webkit-font-smoothing:antialiased}a{color:inherit;text-underline-offset:.22em}header{display:flex;align-items:center;justify-content:space-between;padding:1rem clamp(1rem,5vw,4rem);border-bottom:1px solid var(--line);background:rgba(247,245,239,.95)}.brand{font:700 1.05rem/1.2 var(--serif);text-decoration:none}.back{color:var(--muted);font-size:.88rem}.hero,.article,footer{padding:clamp(3rem,8vw,7rem) max(1.2rem,calc((100vw - 760px)/2))}.hero{background:var(--soft);border-bottom:1px solid var(--line)}.kicker{margin:0 0 1rem;color:var(--accent-dark);font-size:.78rem;font-weight:700;letter-spacing:.17em}h1,h2,h3{font-family:var(--serif);line-height:1.35}h1{max-width:14em;margin:0;font-size:clamp(2.2rem,6vw,4.7rem);letter-spacing:-.035em}.lead{max-width:40rem;margin:1.5rem 0 0;font-size:1.12rem}.article{background:var(--white)}.article h2{margin:3.2rem 0 1rem;font-size:clamp(1.55rem,4vw,2.3rem)}.article h3{margin:2rem 0 .5rem;font-size:1.25rem}.summary{margin:0 0 3rem;padding:1.5rem;border-left:4px solid var(--accent);background:var(--paper)}.summary ul{margin:.4rem 0 0;padding-left:1.3rem}.steps{counter-reset:step;list-style:none;padding:0}.steps li{position:relative;margin:1.4rem 0;padding:1.4rem 1.4rem 1.4rem 4.6rem;border:1px solid var(--line);background:var(--paper)}.steps li:before{counter-increment:step;content:counter(step,decimal-leading-zero);position:absolute;left:1.25rem;top:1.1rem;color:var(--accent-dark);font:700 1.2rem var(--serif)}.note{padding:1rem 1.2rem;background:var(--soft);color:var(--muted)}.cta{margin-top:3.5rem;padding:2rem;background:var(--ink);color:white}.cta h2{margin:0 0 .7rem}.button{display:inline-flex;margin-top:.5rem;padding:.75rem 1.2rem;background:var(--accent);color:white;text-decoration:none;font-weight:700}.pr{display:inline-block;margin-bottom:.6rem;padding:.12rem .45rem;border:1px solid currentColor;font-size:.72rem}.affiliate-link a{display:inline-block;padding:.75rem 1.1rem;background:var(--accent);color:white;font-weight:700;text-decoration:none}footer{padding-top:2rem;padding-bottom:2rem;color:var(--muted);border-top:1px solid var(--line);font-size:.83rem}@media(max-width:600px){.steps li{padding-left:3.8rem}.hero,.article,footer{padding-left:1.1rem;padding-right:1.1rem}}