:root{--paper:#fbfaf6;--card:#fff;--ink:#16201e;--muted:#5d6865;--line:#e5e7df;--green:#008c68;--green-dark:#05664f;--mint:#dff4eb;--amber:#e28a2b;--blue:#286d91;--navy:#102c27;--shadow:0 20px 55px -35px rgba(9,50,42,.42);--radius:20px;--max:1160px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Inter,"Segoe UI",system-ui,-apple-system,sans-serif;line-height:1.65}a{color:var(--green-dark);text-decoration-thickness:.08em;text-underline-offset:.18em}img{max-width:100%;height:auto}h1,h2,h3{line-height:1.12;letter-spacing:-.025em;margin:0 0 .65em}h1{font-size:clamp(2.55rem,6vw,5.4rem);max-width:950px}h2{font-size:clamp(1.9rem,3.5vw,3.15rem)}h3{font-size:1.2rem}p{margin:.6em 0 1.1em}.wrap{width:min(calc(100% - 40px),var(--max));margin:auto}.skip{position:absolute;left:-9999px}.skip:focus{left:18px;top:14px;z-index:99;background:#fff;padding:10px}.site-header{position:sticky;top:0;z-index:50;background:color-mix(in srgb,var(--paper) 92%,transparent);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}.nav-row{min-height:70px;display:flex;align-items:center;gap:24px}.brand{display:flex;align-items:center;gap:9px;color:var(--ink);font-weight:850;text-decoration:none;white-space:nowrap}.brand-mark{display:grid;grid-template-columns:repeat(2,8px);gap:3px}.brand-mark i{width:8px;height:8px;border-radius:50%;background:var(--green)}.brand-mark i:nth-child(2){background:var(--amber)}.brand-mark i:nth-child(3){background:var(--blue)}.brand-mark i:nth-child(4){background:var(--ink)}.site-nav{display:flex;align-items:center;gap:21px;margin-left:auto}.site-nav a{color:var(--muted);font-size:.93rem;font-weight:700;text-decoration:none}.site-nav a:hover,.site-nav a[aria-current="page"]{color:var(--green-dark)}.nav-toggle{display:none;margin-left:auto;border:1px solid var(--line);background:var(--card);border-radius:10px;padding:8px 11px;font:inherit}.button{display:inline-flex;align-items:center;justify-content:center;gap:8px;border-radius:999px;padding:12px 20px;font-weight:800;text-decoration:none;border:1px solid transparent;cursor:pointer;font:inherit}.button.primary{background:var(--navy);color:#fff}.button.secondary{border-color:var(--line);color:var(--ink);background:var(--card)}.button.green{background:var(--green);color:#fff}.hero{padding:92px 0 70px;position:relative;overflow:hidden}.hero:before{content:"";position:absolute;width:520px;height:520px;border-radius:50%;background:radial-gradient(circle,var(--mint),transparent 70%);right:-120px;top:-180px;z-index:-1}.eyebrow{text-transform:uppercase;letter-spacing:.16em;font-size:.76rem;font-weight:900;color:var(--green-dark);margin-bottom:17px}.lede{font-size:clamp(1.08rem,2vw,1.3rem);max-width:760px;color:var(--muted)}.hero-actions,.chips{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}.chips a,.chip{border:1px solid var(--line);border-radius:999px;padding:7px 12px;background:var(--card);font-size:.87rem;font-weight:750;color:var(--muted);text-decoration:none}.trust-line{margin-top:24px;color:var(--muted);font-size:.91rem}.section{padding:76px 0}.section.alt{background:#f2f6f2;border-block:1px solid var(--line)}.section-intro{max-width:750px;margin-bottom:34px}.grid{display:grid;gap:20px}.grid.three{grid-template-columns:repeat(3,1fr)}.grid.four{grid-template-columns:repeat(4,1fr)}.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:25px;box-shadow:var(--shadow)}.card p{color:var(--muted)}.card-link{display:block;color:inherit;text-decoration:none;transition:transform .18s,border-color .18s}.card-link:hover{transform:translateY(-3px);border-color:#b9cec5}.icon{width:46px;height:46px;border-radius:14px;display:grid;place-items:center;background:var(--mint);font-size:1.25rem;margin-bottom:18px}.kicker{color:var(--green-dark);font-size:.78rem;font-weight:900;text-transform:uppercase;letter-spacing:.1em}.step{display:flex;gap:18px}.step-number{flex:0 0 38px;height:38px;border-radius:50%;background:var(--navy);color:#fff;display:grid;place-items:center;font-weight:900}.region{padding:34px;background:var(--navy);color:#fff}.region p,.region a{color:#d7e7e2}.book-card{display:grid;grid-template-columns:112px 1fr;gap:20px;align-items:start}.book-card img{border-radius:8px;box-shadow:0 13px 27px -15px #000}.content-hero{padding:70px 0 45px;border-bottom:1px solid var(--line)}.content-hero h1{font-size:clamp(2.4rem,5vw,4.4rem)}.breadcrumbs{font-size:.88rem;color:var(--muted);margin-bottom:24px}.breadcrumbs a{color:var(--muted)}.article-layout{display:grid;grid-template-columns:minmax(0,760px) 270px;gap:56px;align-items:start}.article{font-size:1.04rem}.article h2{font-size:2rem;margin-top:2em}.article h3{margin-top:1.7em}.article li{margin-bottom:.55em}.article table{border-collapse:collapse;width:100%;margin:25px 0;font-size:.94rem}.article th,.article td{padding:13px;border:1px solid var(--line);text-align:left;vertical-align:top}.article th{background:#edf4f0}.note{border-left:4px solid var(--green);background:var(--mint);padding:18px 21px;border-radius:0 14px 14px 0;margin:24px 0}.warning{border-left-color:var(--amber);background:#fff1df}.toc{position:sticky;top:95px}.toc a{display:block;padding:7px 0;color:var(--muted);text-decoration:none;font-size:.92rem}.meta{display:flex;gap:18px;flex-wrap:wrap;color:var(--muted);font-size:.9rem}.calculator{background:var(--card);border:1px solid var(--line);border-radius:24px;padding:28px;box-shadow:var(--shadow);margin:32px 0}.form-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:17px}.field label{display:block;font-weight:800;margin-bottom:6px}.field input,.field select{width:100%;border:1px solid #cfd6d2;border-radius:11px;padding:12px 13px;background:#fff;color:#18211f;font:inherit}.result{margin-top:22px;padding:22px;border-radius:16px;background:var(--navy);color:#fff}.result strong{font-size:1.65rem;display:block}.result-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.result-grid div{background:rgba(255,255,255,.09);padding:15px;border-radius:12px}.prompt{position:relative;background:#122c27;color:#f8fffc;border-radius:16px;padding:22px;margin:22px 0}.prompt code{white-space:pre-wrap;font:inherit}.copy{position:absolute;top:12px;right:12px;border:1px solid #6e8982;border-radius:999px;background:transparent;color:#fff;padding:7px 11px;cursor:pointer}.source-list li{margin-bottom:12px}.cta-band{background:linear-gradient(120deg,var(--navy),#164e42);color:#fff;border-radius:28px;padding:40px}.cta-band p{color:#d9e7e2;max-width:700px}.site-footer{padding:55px 0 30px;background:#0e211e;color:#d9e7e2}.footer-grid{display:grid;grid-template-columns:1.4fr repeat(3,1fr);gap:34px}.site-footer h3{color:#fff;font-size:1rem}.site-footer a{display:block;color:#c6d7d2;text-decoration:none;margin:7px 0;font-size:.92rem}.legal{border-top:1px solid #29403b;margin-top:35px;padding-top:20px;font-size:.82rem;color:#91aaa3}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
@media(max-width:900px){.grid.three,.grid.four{grid-template-columns:repeat(2,1fr)}.article-layout{grid-template-columns:1fr}.toc{position:static;border-bottom:1px solid var(--line);padding-bottom:25px}.footer-grid{grid-template-columns:repeat(2,1fr)}.site-nav{display:none;position:absolute;top:70px;left:0;right:0;background:var(--paper);padding:20px;flex-direction:column;align-items:flex-start;border-bottom:1px solid var(--line)}.site-nav.open{display:flex}.nav-toggle{display:block}}
@media(max-width:620px){.wrap{width:min(calc(100% - 28px),var(--max))}.hero{padding:64px 0 50px}.section{padding:55px 0}.grid.three,.grid.four,.form-grid,.result-grid,.footer-grid{grid-template-columns:1fr}.book-card{grid-template-columns:86px 1fr}.calculator{padding:19px}.cta-band{padding:28px}.nav-row{min-height:64px}.site-nav{top:64px}}
@media print{.site-header,.site-footer,.hero-actions,.toc,.copy{display:none}.article-layout{display:block}.section{padding:20px 0}}