:root{
 --navy:#071827;--navy2:#0c2942;--blue:#0b72e7;--cyan:#12b8d9;--teal:#0c9b86;
 --ink:#142536;--muted:#647589;--bg:#f3f7fb;--white:#fff;--line:#dce6f0;
 --gold:#f2b84b;--green:#17a568;--red:#df4c4c;--shadow:0 18px 45px rgba(7,24,39,.10)
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,Segoe UI,Arial,sans-serif;line-height:1.7}
a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}.container{width:min(1220px,92%);margin:auto}
.site-header{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.94);backdrop-filter:blur(14px);border-bottom:1px solid rgba(220,230,240,.9)}
.nav-wrap{min-height:74px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;align-items:center;gap:10px;color:var(--navy);font-size:21px;font-weight:900}.brand span span{color:var(--blue)}.brand-mark{width:40px;height:40px;display:grid;place-items:center;color:#fff;border-radius:12px;background:linear-gradient(135deg,var(--navy),var(--blue));box-shadow:0 8px 20px rgba(11,114,231,.25);font-size:13px}
.nav{display:flex;align-items:center;gap:17px}.nav a{font-size:13px;font-weight:750;color:var(--ink)}.menu-btn{display:none;background:none;border:0;font-size:27px}

.hero{position:relative;overflow:hidden;color:#fff;background:radial-gradient(circle at 85% 15%,rgba(18,184,217,.32),transparent 28%),linear-gradient(135deg,#061522,#0b365d 55%,#067b9e);padding:86px 0}
.hero:after{content:"";position:absolute;inset:auto -10% -120px;height:230px;background:rgba(255,255,255,.04);transform:rotate(-4deg)}.hero .container{position:relative;z-index:2}.eyebrow{text-transform:uppercase;letter-spacing:1.7px;font-size:12px;font-weight:900;color:#70e1ff}.hero h1{font-size:clamp(38px,5.4vw,66px);line-height:1.02;max-width:960px;margin:12px 0 18px}.hero p{font-size:19px;max-width:820px;color:#d9ebf8}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}
.btn{display:inline-block;padding:12px 18px;border-radius:11px;font-weight:850;border:1px solid transparent}.btn-primary{background:var(--blue);color:#fff}.btn-light{background:#fff;color:var(--navy)}.btn-outline{background:transparent;color:#fff;border-color:rgba(255,255,255,.35)}

.section{padding:65px 0}.section h2{font-size:34px;line-height:1.2;margin:0 0 12px}.lead{max-width:820px;color:var(--muted)}
.grid{display:grid;gap:20px}.grid-2{grid-template-columns:repeat(2,1fr)}.grid-3{grid-template-columns:repeat(3,1fr)}.grid-4{grid-template-columns:repeat(4,1fr)}
.card{background:var(--white);border:1px solid var(--line);border-radius:18px;padding:25px;box-shadow:var(--shadow)}.card h3{margin:0 0 9px;line-height:1.25}.card p{color:var(--muted)}.card:hover{transform:translateY(-2px);transition:.2s;box-shadow:0 22px 50px rgba(7,24,39,.13)}
.pill{display:inline-block;background:#eaf5ff;color:#0863bd;border:1px solid #d2eaff;padding:5px 10px;border-radius:999px;font-size:11px;font-weight:850;margin:2px}.metric{font-size:35px;font-weight:900;color:var(--blue)}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:15px}.stat{background:#fff;border:1px solid var(--line);border-radius:16px;padding:21px}
.iconbox{width:48px;height:48px;border-radius:14px;display:grid;place-items:center;background:#eaf5ff;color:var(--blue);font-weight:900;margin-bottom:15px}
.article-hero{background:linear-gradient(135deg,#eaf4fc,#fff);border-bottom:1px solid var(--line);padding:64px 0}.article-hero h1{font-size:clamp(35px,4.5vw,57px);line-height:1.06;max-width:980px;margin:10px 0 15px}.article-hero p{font-size:18px;color:var(--muted);max-width:900px}.meta{font-size:13px;color:var(--muted)}
.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:30px;align-items:start}.article{background:#fff;border:1px solid var(--line);border-radius:20px;padding:40px;box-shadow:var(--shadow)}.article h2{font-size:28px;margin:38px 0 10px;line-height:1.25}.article h3{font-size:21px}.article p,.article li{font-size:16px}.article li{margin:7px 0}.article table{width:100%;border-collapse:collapse;margin:20px 0;font-size:14px}.article th,.article td{padding:12px;border:1px solid var(--line);text-align:left}.article th{background:#edf6fd}.formula{background:linear-gradient(135deg,#071827,#0c3658);color:#fff;padding:20px;border-radius:14px;font-size:19px;font-weight:850;margin:20px 0;overflow:auto}.callout{background:#effaff;border:1px solid #c9edf7;border-left:5px solid var(--cyan);padding:17px 19px;border-radius:12px;margin:20px 0}.warning{background:#fff7e9;border:1px solid #f4ddb0;border-left:5px solid var(--gold);padding:17px 19px;border-radius:12px;margin:20px 0}.takeaways{background:#071827;color:#fff;border-radius:18px;padding:25px;margin:25px 0}.takeaways h3{color:#72e1ff}.takeaways li{color:#d9e8f3}.sidebar{position:sticky;top:94px}.sidebar .card{margin-bottom:17px}.toc a{display:block;padding:6px 0;font-size:13px;border-bottom:1px solid #eef2f6}.infographic{display:block;width:100%;height:auto;border:1px solid var(--line);border-radius:17px;margin:0 0 25px;background:#fff;box-shadow:0 10px 30px rgba(7,24,39,.06)}
.article-card{min-height:300px;display:flex;flex-direction:column}.article-card .grow{flex:1}.article-card h3{font-size:20px}.article-card p{font-size:14px}.readmore{font-weight:850}
.search{width:100%;padding:15px;border:1px solid var(--line);border-radius:12px;background:#fff;font-size:15px}.filters{display:flex;gap:8px;flex-wrap:wrap;margin:15px 0}.filter{cursor:pointer;border:1px solid var(--line);background:#fff;padding:8px 13px;border-radius:999px;font-weight:750}.filter.active{background:var(--blue);border-color:var(--blue);color:#fff}
.compare{display:grid;grid-template-columns:1fr 1fr;gap:14px}.compare>div{padding:18px;border-radius:14px;background:#f6f9fc;border:1px solid var(--line)}
.footer{background:#061522;color:#c9d8e4;padding:50px 0 18px;margin-top:50px}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:30px}.footer h3,.footer h4{color:#fff}.footer h3 span{color:#6de1ff}.footer a{display:block;color:#c9d8e4;margin:6px 0}.copyright{border-top:1px solid #22394e;margin-top:30px;padding-top:15px;font-size:12px}
.section-dark{background:#071827;color:#fff}.section-dark .lead{color:#c9d8e4}.cta{background:linear-gradient(135deg,#eaf5ff,#e8fbf8);border:1px solid #cde4ef;border-radius:20px;padding:32px}
@media(max-width:950px){.nav{display:none;position:absolute;top:74px;left:0;right:0;background:#fff;padding:18px;flex-direction:column;align-items:flex-start;border-bottom:1px solid var(--line)}body.nav-open .nav{display:flex}.menu-btn{display:block}.grid-3,.grid-4,.stats{grid-template-columns:1fr 1fr}.article-layout{grid-template-columns:1fr}.sidebar{position:static}.footer-grid{grid-template-columns:1fr 1fr}}
@media(max-width:620px){.grid-2,.grid-3,.grid-4,.stats,.compare{grid-template-columns:1fr}.hero{padding:58px 0}.section{padding:44px 0}.article{padding:24px}.article-hero{padding:48px 0}.footer-grid{grid-template-columns:1fr}}

.process-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;margin:20px 0 28px}.process-step{background:#f5f9fd;border:1px solid #dce6f0;border-radius:15px;padding:16px;min-height:115px;display:flex;flex-direction:column;gap:8px}.process-step b{font-size:12px;color:#0b72e7}.process-step span{font-size:11px;color:#647589}.example-box{background:#eefaf6;border:1px solid #c9ebdf;border-left:5px solid #0c9b86;padding:18px;border-radius:12px}.timeline{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.timeline>div{background:#fff;border:1px solid #dce6f0;border-radius:14px;padding:18px}.timeline b{color:#0b72e7}@media(max-width:800px){.process-grid{grid-template-columns:1fr 1fr}.timeline{grid-template-columns:1fr}}

/* V6 PREMIUM SEO DESIGN SYSTEM */
:root{--navy:#061321;--navy2:#0b2238;--blue:#0878f9;--cyan:#16c7e8;--teal:#12b886;--ink:#12263a;--muted:#65778a;--bg:#f5f8fc;--white:#fff;--line:#dce6f0;--gold:#ffbf55;--shadow:0 20px 60px rgba(7,24,39,.12);--shadow2:0 10px 30px rgba(7,24,39,.08)}
body{background:linear-gradient(180deg,#f7faff 0%,#f3f7fb 100%);font-family:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",Arial,sans-serif}
.site-header{box-shadow:0 4px 24px rgba(5,24,40,.06)}
.nav a{position:relative}.nav a:after{content:"";position:absolute;left:0;right:100%;bottom:-8px;height:2px;background:var(--blue);transition:.25s}.nav a:hover:after{right:0}.nav a:hover{text-decoration:none}
.hero{min-height:610px;display:flex;align-items:center;background:radial-gradient(circle at 75% 22%,rgba(22,199,232,.34),transparent 22%),radial-gradient(circle at 15% 80%,rgba(8,120,249,.25),transparent 26%),linear-gradient(135deg,#04111e,#0a3152 56%,#075e7c);isolation:isolate}
.hero:before{content:"";position:absolute;width:520px;height:520px;border:1px solid rgba(255,255,255,.08);border-radius:50%;right:-140px;top:30px;box-shadow:0 0 0 80px rgba(255,255,255,.018),0 0 0 160px rgba(255,255,255,.012)}
.hero h1{letter-spacing:-2px;text-shadow:0 8px 35px rgba(0,0,0,.18)}
.hero p{line-height:1.8}.eyebrow{display:inline-flex;padding:7px 12px;border:1px solid rgba(112,225,255,.25);border-radius:999px;background:rgba(255,255,255,.06);backdrop-filter:blur(10px)}
.btn{transition:transform .2s,box-shadow .2s}.btn:hover{transform:translateY(-2px);box-shadow:0 10px 25px rgba(8,120,249,.22);text-decoration:none}.btn-primary{background:linear-gradient(135deg,#0878f9,#075dcc)}
.section h2{letter-spacing:-.7px}.lead{max-width:760px}
.card{background:rgba(255,255,255,.88);box-shadow:var(--shadow2);border:1px solid rgba(220,230,240,.9);transition:transform .22s,box-shadow .22s,border-color .22s}.card:hover{transform:translateY(-5px);box-shadow:var(--shadow);border-color:#c7dff5}.article-card{position:relative;overflow:hidden}.article-card:before{content:"";position:absolute;left:0;top:0;width:100%;height:4px;background:linear-gradient(90deg,var(--blue),var(--cyan),var(--teal));transform:scaleX(0);transform-origin:left;transition:.25s}.article-card:hover:before{transform:scaleX(1)}
.stat{background:rgba(255,255,255,.92);border:1px solid var(--line);box-shadow:var(--shadow2);border-radius:18px}.metric{font-size:34px;font-weight:950;background:linear-gradient(135deg,var(--blue),var(--teal));-webkit-background-clip:text;background-clip:text;color:transparent}
.section-dark{background:linear-gradient(135deg,#061522,#092d48);position:relative;overflow:hidden}.section-dark:before{content:"";position:absolute;width:500px;height:500px;border-radius:50%;border:1px solid rgba(255,255,255,.07);right:-250px;top:-200px}
.article-hero{background:radial-gradient(circle at 80% 15%,rgba(22,199,232,.2),transparent 25%),linear-gradient(135deg,#061522,#0b365d);color:#fff;padding:76px 0;position:relative;overflow:hidden}.article-hero:after{content:"";position:absolute;inset:auto -10% -100px;height:180px;background:rgba(255,255,255,.035);transform:rotate(-3deg)}.article-hero .container{position:relative;z-index:2}.article-hero h1{font-size:clamp(38px,5vw,62px);max-width:900px;line-height:1.06;letter-spacing:-1.7px}.article-hero p{max-width:820px;color:#d5e8f5;font-size:18px}.article-hero .meta{color:#a9c6d8}
.article{border-radius:22px;box-shadow:var(--shadow);border:1px solid var(--line)}.article h2{font-size:29px;letter-spacing:-.5px;margin-top:44px}.article h3{font-size:20px}.article p,.article li{font-size:16px}.article .infographic{background:linear-gradient(180deg,#f7fbff,#eef7ff);border-radius:18px;border:1px solid var(--line);padding:12px;box-shadow:var(--shadow2)}
.article-topbar{display:flex;justify-content:space-between;align-items:center;gap:15px;flex-wrap:wrap;margin:0 0 22px;padding-bottom:15px;border-bottom:1px solid var(--line)}.reading{font-size:13px;color:var(--muted);font-weight:750}.share a{display:inline-flex;width:34px;height:34px;align-items:center;justify-content:center;border:1px solid var(--line);border-radius:10px;color:var(--ink);background:#fff;font-weight:900}.share a:hover{background:#eef6ff;text-decoration:none}
.progress-wrap{position:fixed;top:0;left:0;right:0;height:3px;z-index:200;background:transparent}.progress-bar{height:100%;width:0;background:linear-gradient(90deg,var(--blue),var(--cyan),var(--teal))}
.sidebar .card{position:relative}.toc a{display:block;padding:7px 0;border-bottom:1px dashed var(--line);font-size:13px}.sidebar{position:sticky;top:94px;height:max-content}.sidebar .card:first-child{max-height:70vh;overflow:auto}
.faq{margin-top:24px}.faq details{background:#fff;border:1px solid var(--line);border-radius:13px;margin:10px 0;padding:15px 17px;box-shadow:0 5px 18px rgba(7,24,39,.04)}.faq summary{cursor:pointer;font-weight:850}.faq p{margin:12px 0 0;color:var(--muted)}
.seo-strip{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:25px 0}.seo-strip>div{padding:16px;border:1px solid var(--line);border-radius:14px;background:linear-gradient(135deg,#fff,#f3f9ff)}.seo-strip b{display:block;color:var(--blue);font-size:13px}.seo-strip span{font-size:12px;color:var(--muted)}
.breadcrumbs{font-size:13px;color:#7890a2;margin:18px 0}.breadcrumbs a{color:var(--blue)}
.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.related-card{padding:18px;border:1px solid var(--line);border-radius:14px;background:#fff}.related-card h3{font-size:16px;margin:5px 0}.related-card span{font-size:11px;text-transform:uppercase;letter-spacing:1px;color:var(--blue);font-weight:900}
.footer{background:linear-gradient(135deg,#04111e,#082943)}
@media(max-width:800px){.seo-strip,.related-grid{grid-template-columns:1fr}.article h2{font-size:25px}}