:root{--orange:#ff5a00;--orange-dark:#d94d00;--ink:#111820;--navy:#071521;--muted:#5d6873;--line:#e6e9ed;--soft:#f6f7f8;--white:#fff;--green:#eaf7ef;--green-text:#17633a;--amber:#fff7e5}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Arial,Helvetica,sans-serif;color:var(--ink);background:#fff;line-height:1.45}a{text-decoration:none;color:inherit}.container{width:min(1180px,92%);margin:auto}
.site-header{position:absolute;inset:0 0 auto;z-index:20;padding:18px 0;color:#fff}.nav-wrap{display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:10px}.logo-mark{width:38px;height:38px;border:2px solid var(--orange);display:grid;place-items:center;font-weight:800}.logo-text{font-size:24px;font-weight:800}.logo-text span,.footer-logo span{color:var(--orange)}.logo-text small,.footer-logo small{font-size:.55em}.logo-text em{display:block;font-style:normal;font-size:8px;letter-spacing:1.1px}.main-nav{display:flex;gap:19px;font-size:13px;font-weight:700}.main-nav a{padding:8px 0;border-bottom:2px solid transparent}.main-nav a:hover{color:var(--orange);border-color:var(--orange)}.menu-btn{display:none;background:none;border:0;color:#fff;font-size:28px}
.hero{position:relative;min-height:610px;color:#fff;display:flex;align-items:center;background:linear-gradient(90deg,#06121c 0%,#112838 52%,#071621 100%)}.hero:after{content:"";position:absolute;inset:0;background:radial-gradient(circle at 72% 45%,rgba(255,90,0,.18),transparent 25%)}.hero-overlay{position:absolute;inset:0;background:linear-gradient(90deg,rgba(0,0,0,.32),rgba(0,0,0,.05))}.hero-content{position:relative;z-index:2;padding-top:70px}.eyebrow{color:var(--orange);font-weight:800}.eyebrow.dark{color:var(--orange)}.hero h1{font-size:clamp(48px,7vw,88px);line-height:.92;margin:8px 0 18px;max-width:760px}.hero h1 span{color:var(--orange)}.hero-text{font-size:19px;max-width:600px;color:#edf1f4}.hero-actions{display:flex;gap:14px;margin-top:28px}.btn{display:inline-flex;align-items:center;justify-content:center;padding:14px 22px;border-radius:3px;font-size:13px;font-weight:800;text-transform:uppercase;border:1px solid transparent;cursor:pointer}.btn.primary{background:var(--orange);color:#fff}.btn.primary:hover{background:var(--orange-dark)}.btn.secondary{border-color:#fff;color:#fff;background:rgba(0,0,0,.2)}.hero-dots{position:absolute;bottom:34px;left:50%;display:flex;gap:7px;z-index:3}.hero-dots span{width:7px;height:7px;background:#fff;border-radius:50%;opacity:.65}.hero-dots .on{background:var(--orange);opacity:1}
.search-strip{margin-top:-31px;position:relative;z-index:5}.search-inner{background:#07121c;color:#fff;min-height:72px;border-radius:4px;display:grid;grid-template-columns:1.2fr 1fr;align-items:center;padding:14px 24px;box-shadow:0 8px 22px rgba(0,0,0,.25)}.search-inner input{width:100%;background:transparent;border:0;border-right:1px solid #283540;padding:13px 14px;color:#fff;outline:0}.popular{display:flex;gap:16px;flex-wrap:wrap;padding-left:25px;font-size:12px}.popular a{color:var(--orange)}
.section{padding:64px 0}.topics{padding-top:42px}.topic-grid{display:grid;grid-template-columns:repeat(8,1fr);gap:10px}.topic-card{border:1px solid var(--line);padding:18px 12px;text-align:center;box-shadow:0 5px 14px rgba(20,30,40,.06);background:#fff}.icon,.calc-icon{color:var(--orange);font-size:30px}.topic-card h3{font-size:14px;margin:10px 0 6px}.topic-card p{font-size:11px;color:var(--muted);margin:0}.section-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:24px}.section-head h2,.calculator-intro h2{font-size:32px;text-transform:uppercase;margin:0}.section-head a{color:var(--orange);font-weight:700;font-size:13px}
.article-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}.article-card{border:1px solid var(--line);background:#fff;box-shadow:0 5px 14px rgba(20,30,40,.06)}.article-img{height:170px}.img-one{background:linear-gradient(135deg,#2b3035,#7d6755)}.img-two{background:linear-gradient(135deg,#111,#ff6a00)}.img-three{background:linear-gradient(135deg,#7c8994,#1c2a32)}.img-four{background:radial-gradient(circle,#ff6a00 5%,#30160b 55%,#111)}.article-body{padding:18px}.article-body h3{margin:0 0 9px;font-size:18px}.article-body p{color:var(--muted);font-size:13px}.article-body small{color:#8b949c}
.calculators{background:var(--soft)}.calculator-layout{display:grid;grid-template-columns:220px 1fr;gap:36px;align-items:start}.calculator-intro p{color:var(--muted)}.calculator-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:14px}.calculator-grid a{background:#fff;border:1px solid var(--line);padding:24px 18px;min-height:200px;box-shadow:0 5px 14px rgba(20,30,40,.05)}.calculator-grid h3{font-size:15px}.calculator-grid p{font-size:12px;color:var(--muted)}
.problem-banner{background:linear-gradient(90deg,#07121c,#0f1f2b);color:#fff;padding:42px 0}.problem-inner{display:grid;grid-template-columns:1.2fr auto 1fr;align-items:center;gap:28px}.problem-kicker{color:var(--orange);font-weight:800;margin:0}.problem-inner h2{font-size:34px;margin:0}.problem-inner p{color:#c4ccd2}.problem-points{display:flex;gap:18px;flex-wrap:wrap;color:#dfe5e9;font-size:12px}
.dual-feature{background:#fff}.dual-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px}.dual-card{border:1px solid var(--line);padding:28px;box-shadow:0 5px 14px rgba(20,30,40,.05)}.dual-card h2{font-size:28px;margin:4px 0}.dual-card p{color:var(--muted)}.dual-card b{color:var(--orange)}
.center{text-align:center;text-transform:uppercase}.center span{color:var(--orange)}.why-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:20px;margin-top:40px}.why-grid article{text-align:center;padding:8px}.round-icon{width:54px;height:54px;border:1px solid #cbd1d6;border-radius:50%;display:grid;place-items:center;margin:0 auto 14px;font-size:22px}.why-grid h3{font-size:15px}.why-grid p{font-size:12px;color:var(--muted)}
.page-hero{background:linear-gradient(100deg,#06121b,#102c3b);color:#fff;padding:130px 0 55px}.page-hero h1{font-size:48px;margin:4px 0}.page-hero p{max-width:680px;color:#ced7dd}
.solver-layout{display:grid;grid-template-columns:260px 1fr;gap:28px}.problem-picker{background:#071621;color:white;padding:18px;border-radius:4px;height:max-content}.problem-picker h3{margin-top:0}.problem-picker button{width:100%;text-align:left;background:transparent;border:0;border-bottom:1px solid #243540;color:white;padding:14px 8px;cursor:pointer}.problem-picker button:hover,.problem-picker button.active{color:var(--orange);background:#102631}.solver-panel{border:1px solid var(--line);padding:28px;min-height:460px}.dynamic-form{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.dynamic-form .full{grid-column:1/-1}.dynamic-form label{font-size:12px;font-weight:800;color:#35414a}.dynamic-form input,.dynamic-form textarea{width:100%;padding:12px;border:1px solid #cfd6da;border-radius:3px}.hidden{display:none}.analysis-result{margin-top:24px}.result-header{background:#071621;color:white;padding:18px}.result-header h3{margin:0}.result-kpis{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:15px 0}.result-kpis div{background:var(--green);padding:15px;border-left:3px solid #2f9b5c}.result-kpis small{display:block;color:#52705f}.result-kpis b{font-size:18px;color:var(--green-text)}.diagnosis-box{border:1px solid var(--line);padding:18px;margin-top:12px}.diagnosis-box h4{margin-top:0}.warning{background:var(--amber);border-left:4px solid #e4a600;padding:14px}
.calc-section{display:grid;grid-template-columns:.7fr 1.3fr;gap:36px;align-items:start}.calc-copy h2{font-size:30px}.calc-copy p{color:var(--muted)}.standalone-calc{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.standalone-calc label{font-size:12px;font-weight:700}.standalone-calc input{display:block;width:100%;padding:12px;margin-top:6px;border:1px solid #cfd6da}.standalone-calc button,.standalone-calc .calc-result{grid-column:1/-1}.calc-result{background:#071621;color:#fff;padding:18px;min-height:60px}.alt{background:var(--soft)}
.chat-shell{max-width:850px}.chat-messages{height:430px;overflow-y:auto;border:1px solid var(--line);background:#f7f9fa;padding:18px}.msg{max-width:82%;padding:12px 14px;border-radius:8px;margin:10px 0;white-space:pre-wrap}.msg.bot{background:white;border:1px solid var(--line)}.msg.user{background:#071621;color:white;margin-left:auto}.chat-input{display:grid;grid-template-columns:1fr auto;gap:10px;margin-top:12px}.chat-input input{padding:13px;border:1px solid #cfd6da}.small-note{font-size:12px;color:var(--muted)}
.service-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.service-card{border:1px solid var(--line);padding:25px;box-shadow:0 4px 14px rgba(0,0,0,.05)}.service-card p{color:var(--muted)}.upload-note{margin-top:30px;background:#fff6ef;border-left:4px solid var(--orange);padding:18px}.article-list{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}.article-list article{border:1px solid var(--line);padding:22px}.article-list p,.prose p{color:var(--muted)}.prose{max-width:850px}
.site-footer{background:#07121c;color:#fff;padding:48px 0 18px}.footer-grid{display:grid;grid-template-columns:1.4fr repeat(3,1fr);gap:45px}.footer-logo{font-size:23px;font-weight:800}.site-footer p,.site-footer a{display:block;color:#b9c2c9;font-size:13px;margin:8px 0}.site-footer h4{font-size:14px;text-transform:uppercase}.footer-bottom{border-top:1px solid #26333d;margin-top:30px;padding-top:18px;display:flex;justify-content:space-between;gap:20px;color:#8e99a1;font-size:12px}
@media(max-width:980px){.menu-btn{display:block}.main-nav{display:none;position:absolute;top:70px;right:4%;background:#07121c;padding:18px;flex-direction:column;width:230px}.main-nav.open{display:flex}.topic-grid{grid-template-columns:repeat(4,1fr)}.article-grid{grid-template-columns:repeat(2,1fr)}.calculator-layout,.calc-section{grid-template-columns:1fr}.calculator-grid{grid-template-columns:repeat(2,1fr)}.problem-inner{grid-template-columns:1fr}.dual-grid{grid-template-columns:1fr}.why-grid{grid-template-columns:repeat(3,1fr)}.solver-layout{grid-template-columns:1fr}.problem-picker{display:grid;grid-template-columns:repeat(2,1fr);gap:4px}.result-kpis{grid-template-columns:repeat(2,1fr)}.service-grid{grid-template-columns:1fr}.footer-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:640px){.brand-tag{display:none}.logo-text{font-size:19px}.hero{min-height:560px}.hero h1{font-size:48px}.hero-text{font-size:16px}.hero-actions{flex-direction:column;align-items:flex-start}.search-inner{grid-template-columns:1fr}.search-inner input{border-right:0;border-bottom:1px solid #283540}.popular{padding:14px 0 0}.topic-grid{grid-template-columns:repeat(2,1fr)}.article-grid,.calculator-grid,.why-grid,.footer-grid,.standalone-calc,.dynamic-form,.problem-picker{grid-template-columns:1fr}.dynamic-form .full,.standalone-calc button,.standalone-calc .calc-result{grid-column:auto}.footer-bottom{flex-direction:column}.page-hero h1{font-size:38px}.chat-messages{height:390px}}

.badge{display:inline-block;padding:6px 9px;border-radius:999px;font-size:11px;font-weight:800;margin-bottom:8px}
.badge.green{background:#e9f8ef;color:#17633a}
.badge.amber{background:#fff3d7;color:#8a5b00}
.badge.red{background:#ffeded;color:#9a1b1b}
.prose{max-width:850px}.prose p{color:#66717b}