:root{--brand:#ea580c;--brand-600:#ea580c;--brand-700:#c2410c;--brand-50:#fff7ed;--brand-100:#ffedd5;--brand-200:#fed7aa;--ink:#111827;--ink-soft:#374151;--ink-muted:#6b7280;--bg:#fff;--line:#e5e7eb;--radius:0.9rem}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;line-height:1.6}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation-duration:.001ms!important;transition-duration:.001ms!important}}
a{color:inherit;text-decoration:none}
img,svg{max-width:100%}
h1,h2,h3{color:var(--ink);line-height:1.25;margin:0 0 .5em}
.container{max-width:1180px;margin:0 auto;padding:0 1rem}
.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}
.skip-link{position:absolute;left:-999px;top:0;z-index:60;background:var(--brand-600);color:#fff;padding:.5rem 1rem;border-radius:8px}
.skip-link:focus{left:1rem;top:1rem}
.muted{color:var(--ink-muted)}
/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.4rem;border-radius:var(--radius);padding:.65rem 1.25rem;font-size:.9rem;font-weight:600;cursor:pointer;border:1px solid transparent;transition:background .15s,border-color .15s,color .15s;text-align:center}
.btn:focus-visible{outline:2px solid var(--brand-600);outline-offset:2px}
.btn-primary{background:var(--brand-600);color:#fff}
.btn-primary:hover{background:var(--brand-700)}
.btn-secondary{background:#fff;border-color:var(--line);color:var(--ink)}
.btn-secondary:hover{border-color:var(--brand-200);color:var(--brand-700)}
.btn-ghost{background:transparent;color:var(--ink-soft);padding:.5rem .8rem;border-radius:8px}
.btn-ghost:hover{background:var(--brand-50);color:var(--brand-700)}
/* header */
header#dt-header{position:sticky;top:0;z-index:40;background:rgba(255,255,255,.96);backdrop-filter:blur(8px);border-bottom:1px solid transparent;transition:box-shadow .2s,border-color .2s}
header#dt-header.scrolled{border-color:var(--line);box-shadow:0 1px 3px rgba(0,0,0,.06)}
.nav{display:flex;align-items:center;gap:1rem;height:64px}
.logo{display:flex;align-items:center;gap:.5rem;font-weight:800;font-size:1.15rem}
.logo .mark{width:36px;height:36px;border-radius:10px;background:var(--brand-600);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800}
.logo .accent{color:var(--brand-600)}
.nav-links{display:none;align-items:center;gap:.25rem}
@media(min-width:1024px){.nav-links{display:flex}}
.nav-right{margin-left:auto;display:flex;align-items:center;gap:.5rem}
.search-wrap{position:relative;width:18rem;max-width:40vw}
@media(max-width:1100px){.search-wrap.desktop{display:none}}
.search-input{width:100%;border:1px solid var(--line);border-radius:var(--radius);padding:.6rem .8rem .6rem 2.2rem;font-size:.9rem;background:#fff url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='none' stroke='%236b7280' stroke-width='2' viewBox='0 0 24 24'%3E%3Ccircle cx='11' cy='11' r='7'/%3E%3Cpath d='m21 21-4.3-4.3'/%3E%3C/svg%3E") no-repeat .7rem center}
.search-input:focus{outline:none;border-color:var(--brand-600);box-shadow:0 0 0 3px var(--brand-100)}
.search-results{position:absolute;z-index:50;top:calc(100% + .4rem);left:0;width:100%;max-height:24rem;overflow:auto;background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 12px 30px rgba(0,0,0,.12);list-style:none;margin:0;padding:.4rem 0;display:none}
.search-results li{margin:0}
.search-results li a{display:block;padding:.5rem 1rem}
.search-results li.active,.search-results li a:hover{background:var(--brand-50)}
.search-results .r-name{display:block;font-weight:500;font-size:.9rem}
.search-results .r-cat{display:block;font-size:.75rem;color:var(--ink-muted)}
.search-results .no-res{padding:.7rem 1rem;font-size:.85rem;color:var(--ink-muted)}
.icon-btn{background:transparent;border:0;cursor:pointer;font-size:1.2rem;padding:.4rem .6rem;border-radius:8px;color:var(--ink-soft)}
.icon-btn:hover{background:var(--brand-50)}
.lg-only{display:none}@media(min-width:1024px){.lg-only{display:inline-flex}.hide-lg{display:none!important}}
/* mega menu */
.mega-wrap{position:relative}
.mega{display:none;position:absolute;left:50%;transform:translateX(-50%);top:100%;padding-top:.5rem;width:min(92vw,860px);z-index:50}
.mega-inner{background:#fff;border:1px solid var(--line);border-radius:1rem;box-shadow:0 16px 40px rgba(0,0,0,.14);padding:1.4rem;display:grid;grid-template-columns:repeat(3,1fr);gap:1rem 1.5rem}
.mega-col h4{margin:0 0 .4rem;font-size:.9rem}
.mega-col h4 a{display:flex;gap:.4rem;align-items:center}
.mega-col ul{list-style:none;margin:.2rem 0 0;padding:0}
.mega-col li a{font-size:.78rem;color:var(--ink-muted);display:block;padding:.1rem 0}
.mega-col li a:hover{color:var(--brand-600)}
/* drawer */
#dt-drawer{display:none;position:fixed;inset:0;z-index:50;background:rgba(0,0,0,.4)}
.drawer-panel{position:absolute;right:0;top:0;height:100%;width:20rem;max-width:85vw;background:#fff;padding:1.25rem;overflow:auto;box-shadow:-10px 0 30px rgba(0,0,0,.2)}
.drawer-panel a{display:block;padding:.5rem .7rem;border-radius:8px;font-size:.95rem}
.drawer-panel a:hover{background:var(--brand-50)}
.drawer-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:.8rem;font-weight:700}
.drawer-panel .sec{margin:.8rem 0 .3rem;font-size:.72rem;text-transform:uppercase;letter-spacing:.05em;color:var(--ink-muted);padding:0 .7rem}
/* hero */
.hero{background:linear-gradient(to bottom,var(--brand-50),#fff);padding:4rem 0}
.hero-inner{max-width:48rem;margin:0 auto;text-align:center}
.hero h1{font-size:2.4rem;font-weight:800;letter-spacing:-.02em}
@media(min-width:640px){.hero h1{font-size:3rem}}
.hero p{font-size:1.1rem;color:var(--ink-soft)}
.hero .search-wrap{width:100%;max-width:36rem;margin:1.5rem auto 0}
.hero .search-input{padding-top:.85rem;padding-bottom:.85rem;font-size:1rem}
.cta-row{display:flex;flex-wrap:wrap;gap:.75rem;justify-content:center;margin-top:1.25rem}
.chip{display:inline-flex;align-items:center;border:1px solid var(--line);background:#f9fafb;border-radius:999px;padding:.25rem .75rem;font-size:.75rem;font-weight:500;color:var(--ink-soft)}
.chip.brand{border-color:var(--brand-200);background:var(--brand-100);color:var(--brand-700)}
/* sections */
section{padding:3.5rem 0}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;gap:1rem;margin-bottom:1.5rem}
.sec-head h2{font-size:1.6rem;font-weight:700}
.sec-head .sub{color:var(--ink-muted);margin-top:.2rem}
.sec-link{font-size:.9rem;font-weight:600;color:var(--brand-600);white-space:nowrap}
.sec-link:hover{text-decoration:underline}
.bg-soft{background:#f9fafb}
/* grids & cards */
.grid{display:grid;gap:1rem;grid-template-columns:1fr}
@media(min-width:640px){.grid{grid-template-columns:repeat(2,1fr)}}
@media(min-width:1024px){.grid-3{grid-template-columns:repeat(3,1fr)}.grid-4{grid-template-columns:repeat(4,1fr)}}
.card{border:1px solid var(--line);border-radius:1rem;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.06);transition:transform .15s,box-shadow .15s,border-color .15s}
.calc-card{display:flex;flex-direction:column;gap:.5rem;padding:1.25rem}
.calc-card:hover{transform:translateY(-2px);border-color:var(--brand-200);box-shadow:0 12px 30px -12px rgba(234,88,12,.3)}
.calc-card .top{display:flex;justify-content:space-between;align-items:flex-start;gap:.5rem}
.calc-card .icon{font-size:1.5rem}
.calc-card h3{font-size:1rem;font-weight:600;margin:0}
.calc-card:hover h3{color:var(--brand-700)}
.calc-card .desc{font-size:.85rem;color:var(--ink-muted);margin:0;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.calc-card .open{margin-top:auto;padding-top:.4rem;font-size:.85rem;font-weight:600;color:var(--brand-600)}
.cat-card{display:flex;align-items:center;gap:.75rem;padding:1rem}
.cat-card .icon{font-size:1.5rem}
.cat-card .nm{font-weight:600;font-size:.9rem}
.cat-card .ct{font-size:.75rem;color:var(--ink-muted)}
/* breadcrumbs */
.crumbs{font-size:.85rem;color:var(--ink-muted);padding:1.5rem 0 0}
.crumbs a:hover{color:var(--brand-700);text-decoration:underline}
.crumbs .sep{padding:0 .4rem;color:#d1d5db}
/* calculator page */
.calc-layout{display:grid;gap:2rem;grid-template-columns:1fr;margin-top:1rem}
@media(min-width:1024px){.calc-layout{grid-template-columns:3fr 2fr}}
.page-h1{font-size:2rem;font-weight:800;margin:1rem 0 .3rem}
@media(min-width:640px){.page-h1{font-size:2.3rem}}
.lead{color:var(--ink-soft);margin:.3rem 0 0}
/* calc widget */
.calc-box{border:1px solid var(--line);border-radius:1.25rem;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.06);padding:1.5rem}
.calc-grid{display:grid;gap:1rem;grid-template-columns:1fr}
@media(min-width:640px){.calc-grid{grid-template-columns:repeat(2,1fr)}}
.col-span-2{grid-column:1/-1}
.label{display:block;font-size:.85rem;font-weight:500;color:var(--ink-soft);margin-bottom:.25rem}
.field{width:100%;border:1px solid var(--line);border-radius:var(--radius);padding:.6rem .85rem;font-size:.95rem;background:#fff;color:var(--ink)}
.field:focus{outline:none;border-color:var(--brand-600);box-shadow:0 0 0 3px var(--brand-100)}
.help{font-size:.75rem;color:var(--ink-muted);margin:.25rem 0 0}
.err{font-size:.75rem;font-weight:500;color:#dc2626;margin:.25rem 0 0}
.btn-row{display:flex;flex-wrap:wrap;gap:.75rem;grid-column:1/-1;margin-top:.25rem}
.result-area{margin-top:1.5rem}
.err-box{border:1px solid #fecaca;background:#fef2f2;color:#b91c1c;padding:.75rem 1rem;border-radius:var(--radius);font-size:.9rem}
.result{border:1px solid var(--brand-200);background:rgba(255,247,237,.6);border-radius:1.25rem;padding:1.25rem}
.result-head{display:flex;justify-content:space-between;align-items:center}
.result-head h3{font-size:.8rem;text-transform:uppercase;letter-spacing:.05em;color:var(--brand-700);margin:0}
.result-actions{display:flex;gap:.5rem}
.mini{border:1px solid var(--brand-200);background:#fff;color:var(--brand-700);border-radius:8px;padding:.2rem .6rem;font-size:.75rem;font-weight:500;cursor:pointer}
.mini:hover{background:var(--brand-100)}
.out-grid{display:grid;gap:.75rem;grid-template-columns:1fr;margin-top:.75rem}
@media(min-width:640px){.out-grid{grid-template-columns:repeat(2,1fr)}}
.out-card{background:#fff;border-radius:var(--radius);padding:.75rem 1rem;box-shadow:0 1px 2px rgba(0,0,0,.05)}
.out-label{font-size:.75rem;color:var(--ink-muted)}
.out-val{font-size:1.35rem;font-weight:700}
.chart{display:flex;flex-wrap:wrap;align-items:center;gap:1.25rem;margin-top:1rem}
.legend{list-style:none;margin:0;padding:0;font-size:.85rem}
.legend li{display:flex;align-items:center;gap:.5rem;color:var(--ink-soft)}
.legend .dot{width:12px;height:12px;border-radius:3px;display:inline-block}
.steps{margin-top:1rem}
.steps summary{cursor:pointer;font-size:.9rem;font-weight:600;color:var(--brand-700)}
.steps ol{background:#fff;border-radius:var(--radius);padding:1rem 1rem 1rem 2rem;margin-top:.5rem}
.steps li{font-family:ui-monospace,Menlo,Consolas,monospace;font-size:.78rem;color:var(--ink-soft)}
.formula-box{margin-top:1rem;background:#f9fafb;border-radius:var(--radius);padding:.75rem 1rem}
.formula-box span{font-weight:600}
.formula-box{font-family:ui-monospace,Menlo,Consolas,monospace;font-size:.8rem;color:var(--ink-soft)}
.disc{margin-top:.75rem;font-size:.75rem;color:var(--ink-muted)}
/* sidebar */
.side-card{border:1px solid var(--line);border-radius:1rem;background:#fff;padding:1.25rem}
.side-card h2{font-size:.8rem;text-transform:uppercase;letter-spacing:.05em;color:var(--ink-muted)}
.facts{margin:.6rem 0 0;font-size:.88rem}
.facts div{display:flex;justify-content:space-between;gap:.5rem;padding:.15rem 0}
.facts dt{color:var(--ink-muted)}
.related-list{list-style:none;margin:.5rem 0 0;padding:0}
.related-list li{margin-bottom:.5rem}
.related-list a{display:flex;justify-content:space-between;gap:.5rem;border:1px solid var(--line);border-radius:var(--radius);padding:.6rem .9rem;font-size:.88rem;font-weight:500}
.related-list a:hover{border-color:var(--brand-200);color:var(--brand-700)}
/* prose */
.prose{max-width:48rem}
.prose h2{font-size:1.5rem;font-weight:700;margin:2rem 0 .75rem}
.prose h3{font-size:1.1rem;font-weight:600;margin:1.5rem 0 .5rem}
.prose p{margin:0 0 1rem;color:var(--ink-soft)}
.prose ul,.prose ol{margin:0 0 1rem;padding-left:1.3rem;color:var(--ink-soft)}
.prose li{margin:.2rem 0}
.prose code{background:#f1f5f9;padding:.1rem .35rem;border-radius:5px;font-size:.85em}
.prose pre{background:#0f172a;color:#e2e8f0;padding:1rem;border-radius:var(--radius);overflow:auto;font-size:.85rem}
.tbl{width:100%;border-collapse:collapse;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;font-size:.9rem}
.tbl th,.tbl td{padding:.5rem .9rem;text-align:left;border-bottom:1px solid var(--line)}
.tbl th{background:#f9fafb;font-weight:500;width:30%}
details.faq{border-bottom:1px solid var(--line);padding:.8rem 0}
details.faq summary{cursor:pointer;font-weight:600}
details.faq p{margin:.5rem 0 0;color:var(--ink-soft)}
.note{margin-top:2rem;border:1px solid #fde68a;background:#fffbeb;color:#92400e;border-radius:var(--radius);padding:.75rem 1rem;font-size:.9rem}
.byline{margin-top:1rem;font-size:.75rem;color:var(--ink-muted)}
.chips{display:flex;flex-wrap:wrap;gap:.5rem}
.chip-link{display:inline-flex;border:1px solid var(--line);border-radius:999px;padding:.3rem .8rem;font-size:.82rem}
.chip-link:hover{border-color:var(--brand-200);color:var(--brand-700)}
.chip-link.brand{border-color:var(--brand-200);background:var(--brand-50);color:var(--brand-700)}
/* directory filters */
.filters{display:grid;gap:.75rem;grid-template-columns:1fr}
@media(min-width:1024px){.filters{grid-template-columns:2fr 1fr 1fr}}
.alpha{display:flex;flex-wrap:wrap;gap:.25rem;margin-top:1rem}
.alpha button{border:0;background:transparent;border-radius:6px;padding:.25rem .55rem;font-size:.85rem;font-weight:500;color:var(--ink-soft);cursor:pointer}
.alpha button[aria-pressed=true]{background:var(--brand-600);color:#fff}
.alpha button:hover{background:var(--brand-50)}
.count{font-size:.85rem;color:var(--ink-muted);margin-top:1rem}
.loadmore{text-align:center;margin-top:2rem}
/* footer */
footer{margin-top:5rem;background:#111827;color:#d1d5db}
.foot-grid{display:grid;gap:2.5rem;padding:3.5rem 0;grid-template-columns:1fr}
@media(min-width:640px){.foot-grid{grid-template-columns:repeat(2,1fr)}}
@media(min-width:1024px){.foot-grid{grid-template-columns:repeat(4,1fr)}}
footer h4{color:#fff;font-size:.8rem;text-transform:uppercase;letter-spacing:.05em;margin:0 0 .75rem}
footer ul{list-style:none;margin:0;padding:0}
footer li{margin:.4rem 0;font-size:.9rem}
footer a:hover{color:var(--brand-200)}
.foot-logo{display:flex;align-items:center;gap:.5rem;color:#fff;font-weight:800;font-size:1.1rem}
.foot-desc{font-size:.85rem;color:#9ca3af;margin:.75rem 0}
.social{display:flex;gap:.6rem;margin-top:.5rem}
.social a{width:36px;height:36px;border-radius:999px;background:#1f2937;display:flex;align-items:center;justify-content:center}
.social a:hover{background:var(--brand-600);color:#fff}
.nl{display:flex;gap:.5rem;margin-top:.5rem}
.nl input{flex:1;border:1px solid #374151;background:#1f2937;color:#fff;border-radius:var(--radius);padding:.5rem .7rem;font-size:.85rem}
.foot-bot{border-top:1px solid #1f2937}
.foot-bot .container{display:flex;flex-wrap:wrap;justify-content:space-between;gap:.5rem;padding:1.25rem 1rem;font-size:.85rem;color:#9ca3af}
/* back to top */
#dt-top{display:none;position:fixed;bottom:1.5rem;right:1.5rem;z-index:30;width:44px;height:44px;border-radius:999px;background:var(--brand-600);color:#fff;border:0;cursor:pointer;align-items:center;justify-content:center;box-shadow:0 8px 20px rgba(0,0,0,.2);font-size:1.1rem}
#dt-top:hover{background:var(--brand-700)}
/* forms */
.form-ok{display:none;border:1px solid #bbf7d0;background:#f0fdf4;color:#166534;border-radius:1rem;padding:1.5rem}
.form-error{display:none;background:#fef2f2;color:#b91c1c;border-radius:8px;padding:.5rem .8rem;font-size:.85rem}
.two-col{display:grid;gap:2.5rem;grid-template-columns:1fr;margin-top:1rem}
@media(min-width:1024px){.two-col{grid-template-columns:1fr 1fr}}
.hp{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}
.notfound{text-align:center;padding:5rem 1rem}
.notfound .code{font-size:4rem;font-weight:800;color:var(--brand-600)}