:root{--ink:#283b39;--green:#3c665b;--cream:#f7f5ef;--line:#d9dfdb;font-family:system-ui,"Noto Sans Thai",sans-serif;color:var(--ink)}*{box-sizing:border-box}body{margin:0;background:var(--cream);line-height:1.72}.shell{width:min(1080px,calc(100% - 36px));margin:auto}.head{display:flex;justify-content:space-between;align-items:center;min-height:72px;border-bottom:1px solid var(--line)}.brand{font-weight:800;text-decoration:none}nav{display:flex;gap:20px}nav a{color:inherit;text-decoration:none}.hero,.split{display:grid;grid-template-columns:1fr 1fr;gap:46px;align-items:center;padding:58px 0}.hero h1{font-size:clamp(2.4rem,5vw,4.4rem);line-height:1.2;margin:.2em 0}.hero figure,.split figure{margin:0}.hero img,.split img{display:block;width:100%;aspect-ratio:1.55;object-fit:cover;border-radius:14px}.tag{font-weight:750;color:var(--green)}.button{display:inline-block;background:var(--green);color:white;text-decoration:none;padding:11px 19px;border-radius:5px;font-weight:750}.muted,figcaption{font-size:.9rem;color:#576663}.split{border-top:1px solid var(--line)}.split h2,.calc h2{font-size:clamp(1.8rem,3vw,2.6rem);line-height:1.25}.reverse figure{order:2}.calc{padding:54px 0;background:#e9eee9}.formula{background:#fff;padding:14px;border-left:4px solid #d7905f}.wide{display:block;max-width:360px;margin:20px 0}.cards{display:grid;grid-template-columns:1fr 1fr;gap:18px}fieldset{background:#fff;border:1px solid #bec9c4;border-radius:12px;padding:18px}legend{font-weight:800}label{display:block;font-weight:650;margin:11px 0}input,textarea{display:block;width:100%;margin-top:5px;padding:10px;border:1px solid #aebdb7;border-radius:6px;background:#fff;font:inherit;color:var(--ink)}input:focus-visible,textarea:focus-visible{outline:3px solid #d6a279}output{display:block;font-size:1.15rem;font-weight:800;margin-top:14px}.diff{font-weight:800}.foot{border-top:1px solid var(--line);padding:24px 0 40px}.skip{position:absolute;left:-9999px}.skip:focus{left:10px;top:10px;padding:8px;background:#fff}@media(max-width:760px){.shell{width:calc(100% - 28px)}.head{align-items:flex-start;flex-direction:column;padding:14px 0;gap:8px}nav{gap:14px;flex-wrap:wrap}.hero,.split{grid-template-columns:1fr;gap:22px;padding:38px 0}.reverse figure{order:0}.cards{grid-template-columns:1fr}.calc{padding:40px 0}}