:root{
--navy:#07111f;
--charcoal:#1d2733;
--muted:#657184;
--line:#dfe6ef;
--soft:#f5f8fb;
--gold:#f4b740;
--green:#39a976;
--blue:#377dff;
--radius:24px;
--shadow:0 24px 70px rgba(7,17,31,.14);
--shadow-soft:0 16px 50px rgba(7,17,31,.08);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;color:var(--charcoal);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:#fff;letter-spacing:0}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
.site-nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.9);backdrop-filter:blur(18px);border-bottom:1px solid rgba(223,230,239,.8)}
.navbar-brand{display:inline-flex;align-items:center;padding:0}
.navbar-brand img{display:block;width:auto;height:44px;max-width:220px;object-fit:contain}
.nav-link{color:#344255;font-weight:650;font-size:.94rem}
.nav-link:hover{color:var(--blue);text-decoration:none}
.btn-premium,.btn-gold,.btn-outline-premium{border-radius:999px;font-weight:800;padding:.85rem 1.15rem;text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:.5rem}
.btn-gold{background:linear-gradient(135deg,#ffd778,#f1a928);color:#161b22;border:0;box-shadow:0 14px 34px rgba(244,183,64,.28)}
.btn-gold:hover{color:#161b22;text-decoration:none;transform:translateY(-1px)}
.btn-premium{background:var(--navy);color:#fff;border:1px solid var(--navy)}
.btn-premium:hover{background:#12243c;color:#fff;text-decoration:none}
.btn-outline-premium{border:1px solid rgba(7,17,31,.18);color:var(--navy);background:#fff}
.btn-outline-premium:hover{background:var(--navy);color:#fff;text-decoration:none}
.hero{position:relative;overflow:hidden;color:#fff;background:linear-gradient(110deg,rgba(7,17,31,.94),rgba(7,17,31,.68) 54%,rgba(7,17,31,.2)),var(--hero-image, url('../images/background-solar-tiles.jpg')) center/cover no-repeat}
.hero-inner{padding:86px 0}
.hero h1{font-size:clamp(2.7rem,6vw,5.8rem);line-height:.96;letter-spacing:-.055em;font-weight:900;max-width:980px}
.hero .lead{font-size:clamp(1.05rem,2vw,1.28rem);color:rgba(255,255,255,.82);max-width:760px;line-height:1.65}
.eyebrow{display:inline-flex;align-items:center;gap:.5rem;padding:.45rem .8rem;border-radius:999px;background:rgba(55,125,255,.1);color:#1f62d7;font-weight:800;font-size:.78rem;text-transform:uppercase;letter-spacing:.08em}
.hero .eyebrow{background:rgba(255,255,255,.12);color:#fff}
.section{padding:86px 0}
.section-soft{background:linear-gradient(180deg,#f7fafc 0%,#fff 100%)}
.display-title{font-size:clamp(2rem,4.3vw,4.2rem);line-height:1;letter-spacing:-.052em;font-weight:900;color:var(--navy)}
.section-lead{font-size:1.1rem;color:var(--muted);line-height:1.7;max-width:760px}
.premium-card{border:1px solid var(--line);border-radius:var(--radius);padding:26px;background:#fff;box-shadow:var(--shadow-soft);height:100%}
.premium-card h2,.premium-card h3,.article-body h2,.article-body h3{color:var(--navy);letter-spacing:-.03em;font-weight:850}
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.stat{padding:18px;border-radius:18px;background:#fff;border:1px solid rgba(255,255,255,.34);box-shadow:var(--shadow-soft)}
.stat strong{display:block;color:var(--navy);font-size:1.35rem;letter-spacing:-.04em}
.stat span{color:var(--muted);font-size:.9rem}
.hero .stat{background:rgba(255,255,255,.1);backdrop-filter:blur(14px)}
.hero .stat strong{color:#fff}
.hero .stat span{color:rgba(255,255,255,.72)}
.article-shell{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:42px;align-items:start}
.article-body{font-size:1.06rem;line-height:1.78;color:#344255}
.article-body h2{font-size:2rem;margin-top:2.2rem;margin-bottom:1rem}
.article-body h3{font-size:1.35rem;margin-top:1.6rem}
.article-body table{font-size:.96rem}
.article-body li{margin:.42rem 0}
.toc-card{position:sticky;top:102px;border:1px solid var(--line);border-radius:22px;padding:22px;background:#fff;box-shadow:var(--shadow-soft)}
.toc-card a{display:block;margin:.58rem 0;color:#344255;font-weight:700}
.cta-panel{position:relative;overflow:hidden;border-radius:32px;background:linear-gradient(135deg,#07111f,#0d2a49 62%,#183b35);color:#fff;padding:40px;box-shadow:var(--shadow)}
.cta-panel h2{color:#fff}
.comparison-table{border:1px solid var(--line);border-radius:24px;overflow-x:auto;overflow-y:hidden;box-shadow:var(--shadow-soft);-webkit-overflow-scrolling:touch}
.comparison-table table{margin:0}
.comparison-table th{background:#f8fbff;color:var(--navy);font-size:.82rem;text-transform:uppercase;letter-spacing:.07em}
.comparison-table td,.comparison-table th{padding:17px;border-color:#edf2f7}
.score{display:inline-flex;border-radius:999px;background:#ecf8f2;color:#17734d;padding:.35rem .65rem;font-weight:850;font-size:.84rem}
.article-card{display:block;height:100%;border:1px solid var(--line);border-radius:24px;overflow:hidden;background:#fff;color:inherit;box-shadow:var(--shadow-soft);transition:transform .2s ease,box-shadow .2s ease}
.article-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);text-decoration:none}
.article-card img{width:100%;height:210px;object-fit:cover;display:block}
.article-card .content{padding:24px}
.article-card h2,.article-card h3{color:var(--navy);font-weight:850;letter-spacing:-.03em}
.badge-soft{display:inline-flex;border-radius:999px;background:#eef4ff;color:#1f62d7;padding:.35rem .65rem;font-weight:850;font-size:.78rem}
.footer{background:#07111f;color:#d9e3ef;padding:54px 0 30px}
.footer h3,.footer h4{color:#fff;font-size:1rem;font-weight:850}
.footer a{display:block;color:#aebdd0;text-decoration:none;margin:.45rem 0}
.footer a:hover{color:#fff}
.small-muted{color:var(--muted);font-size:.93rem}
.breadcrumb-lite{color:rgba(255,255,255,.72);font-weight:700}
.breadcrumb-lite a{color:#fff}
@media (max-width:991px){
.article-shell{grid-template-columns:1fr}
.toc-card{position:static}
.stat-grid{grid-template-columns:repeat(2,1fr)}
.section{padding:68px 0}
}
@media (max-width:767px){
body{overflow-x:hidden}
.row{margin-left:0;margin-right:0}
.navbar-brand img{height:38px;max-width:190px}
.hero-inner{padding:56px 0}
.hero h1{font-size:2.9rem}
.stat-grid{grid-template-columns:1fr}
.cta-panel{padding:28px}
}