:root{
  --brand:#059669; --brand-dark:#047857; --brand-deep:#064e3b; --brand-soft:#ecfdf5;
  --slate:#0f172a; --slate-2:#1e293b; --muted:#64748b; --line:#e2e8f0; --bg:#f6f8f7;
  --card:#ffffff; --green:#059669; --radius:16px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Inter,Arial,sans-serif;
  color:var(--slate);background:var(--bg);line-height:1.6;font-size:16px}
a{color:var(--brand-dark);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:1080px;margin:0 auto;padding:0 18px}
/* header */
.site-header{background:rgba(255,255,255,.97);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:60;
  box-shadow:0 2px 14px rgba(15,23,42,.06)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;min-height:62px;gap:16px}
.brand{font-weight:800;font-size:1.25rem;color:var(--slate);display:flex;align-items:center;gap:9px;
  flex-shrink:0;white-space:nowrap}
.brand .logo{width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,var(--slate),var(--brand-deep));
  display:inline-flex;align-items:center;justify-content:center;color:#fff;font-size:18px;flex-shrink:0;
  box-shadow:0 4px 10px rgba(6,78,59,.35)}
nav.main{display:flex;gap:2px;align-items:center}
nav.main>a{color:var(--slate);font-weight:600;padding:10px 14px;border-radius:10px;font-size:.95rem;white-space:nowrap}
nav.main>a:hover{background:var(--brand-soft);text-decoration:none;color:var(--brand-deep)}
.nav-drop{position:relative}
.nav-drop-btn{background:none;border:none;font:inherit;font-weight:600;color:var(--slate);cursor:pointer;
  padding:10px 14px;border-radius:10px;font-size:.95rem;display:inline-flex;align-items:center;gap:6px;min-height:44px}
.nav-drop-btn:hover,.nav-drop.open .nav-drop-btn{background:var(--brand-soft);color:var(--brand-deep)}
.nav-drop-btn .chev{font-size:.7rem;transition:transform .2s}
.nav-drop.open .nav-drop-btn .chev{transform:rotate(180deg)}
.nav-drop-panel{position:absolute;top:calc(100% + 8px);right:0;width:540px;max-width:92vw;background:#fff;
  border:1px solid var(--line);border-radius:16px;box-shadow:0 24px 50px rgba(15,23,42,.16);padding:12px;
  display:grid;grid-template-columns:1fr 1fr;gap:2px 10px;opacity:0;visibility:hidden;transform:translateY(8px);
  transition:opacity .2s ease,transform .2s ease,visibility .2s}
.nav-drop.open .nav-drop-panel{opacity:1;visibility:visible;transform:translateY(0)}
@media(hover:hover) and (min-width:861px){
  .nav-drop:hover .nav-drop-panel,.nav-drop:focus-within .nav-drop-panel{opacity:1;visibility:visible;transform:translateY(0)}
}
.nav-drop-panel a{color:var(--slate);font-weight:600;font-size:.92rem;padding:10px 12px;border-radius:10px;
  display:flex;align-items:center;gap:10px}
.nav-drop-panel a:hover{background:var(--brand-soft);color:var(--brand-deep);text-decoration:none}
.nav-drop-panel a svg{width:19px;height:19px;color:var(--brand);flex-shrink:0}
#navToggle{display:none;background:none;border:1px solid var(--line);border-radius:10px;font-size:1.25rem;
  padding:8px 13px;cursor:pointer;color:var(--slate);min-height:44px;flex-shrink:0}
/* hero */
@keyframes fadeUp{from{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}
.hero{background:linear-gradient(135deg,#0f172a 0%,#134e4a 55%,#065f46 100%);color:#fff;padding:56px 0 64px;
  position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;right:-90px;top:-90px;width:340px;height:340px;border-radius:50%;
  background:radial-gradient(circle,rgba(255,255,255,.18),rgba(255,255,255,0) 65%)}
.hero .wrap{position:relative;z-index:1}
.hero h1{margin:0 0 12px;font-size:2.1rem;line-height:1.2;letter-spacing:-.02em;animation:fadeUp .6s ease both}
.hero p.sub{opacity:.92;font-size:1.08rem;max-width:640px;margin:0 0 24px;animation:fadeUp .6s ease .1s both}
.btn-cta{display:inline-flex;align-items:center;gap:9px;background:#fff;color:var(--brand-deep);font-weight:800;
  padding:14px 28px;border-radius:999px;font-size:1.02rem;min-height:52px;box-shadow:0 10px 24px rgba(0,0,0,.25);
  transition:transform .25s ease,box-shadow .25s ease;animation:fadeUp .6s ease .18s both;margin:0 0 22px}
.btn-cta:hover{transform:translateY(-2px) scale(1.02);box-shadow:0 16px 32px rgba(0,0,0,.3);text-decoration:none}
.hero-badges{display:flex;gap:10px;flex-wrap:wrap;font-size:.85rem;animation:fadeUp .6s ease .26s both}
.hero-badges span{background:rgba(255,255,255,.16);padding:6px 14px;border-radius:999px}
/* tool cards */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:18px;margin:36px 0}
.tool-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;display:block;
  transition:transform .25s ease,box-shadow .25s ease,border-color .25s ease;animation:fadeUp .55s ease both}
.tool-card:hover{transform:translateY(-5px);box-shadow:0 18px 34px rgba(6,78,59,.16);border-color:#a7f3d0;text-decoration:none}
.tool-card .icon{width:52px;height:52px;border-radius:14px;background:linear-gradient(135deg,var(--brand-soft),#d1fae5);
  display:flex;align-items:center;justify-content:center;margin-bottom:14px;color:var(--brand-dark)}
.tool-card .icon svg{width:27px;height:27px}
.tool-card h3{margin:0 0 8px;font-size:1.15rem;color:var(--slate)}
.tool-card p{margin:0;color:var(--muted);font-size:.94rem}
/* tool page layout */
.tool-hero{background:linear-gradient(135deg,#0f172a,#065f46);color:#fff;padding:40px 0}
.tool-hero h1{margin:0 0 8px;font-size:1.8rem;letter-spacing:-.02em;animation:fadeUp .5s ease both}
.tool-hero p{margin:0;opacity:.9;max-width:680px;animation:fadeUp .5s ease .08s both}
.calculator{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px;margin:-34px 0 30px;box-shadow:0 10px 30px rgba(15,23,42,.08);position:relative}
.field{margin-bottom:16px}
.field label{display:block;font-weight:700;margin-bottom:6px;font-size:.95rem}
.field input,.field select{width:100%;padding:12px 14px;border:1.5px solid var(--line);border-radius:12px;
  font-size:1rem;font-family:inherit}
.field input:focus,.field select:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-soft)}
.field .hint{font-weight:400;color:var(--muted);font-size:.85rem;margin-top:4px}
.field-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.field-row3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:14px}
.btn{background:linear-gradient(135deg,var(--brand) 0%,var(--brand-dark) 100%);color:#fff;border:none;border-radius:12px;
  padding:14px 26px;font-size:1rem;font-weight:700;cursor:pointer;width:100%;min-height:50px;
  box-shadow:0 8px 18px rgba(5,150,105,.25);transition:transform .25s ease,box-shadow .25s ease,filter .25s ease}
.btn:hover{background:linear-gradient(135deg,var(--brand-dark) 0%,var(--brand-deep) 100%);transform:translateY(-1px);
  box-shadow:0 12px 24px rgba(5,150,105,.32);filter:brightness(1.03)}
.btn:active{transform:translateY(0) scale(.99)}
.btn-ghost{background:var(--brand-soft);color:var(--brand-deep);box-shadow:none}
.result{background:#f0fdf4;border:1.5px solid #bbf7d0;border-radius:12px;padding:18px;margin-top:18px;display:none}
.result.show{display:block}
.result .big{font-size:1.9rem;font-weight:800;color:var(--green)}
.result .detail{color:var(--muted);font-size:.92rem;margin-top:6px}
.result .warn{color:#b45309;font-weight:700;margin-top:6px}
.tabs{display:flex;gap:8px;margin-bottom:18px;flex-wrap:wrap}
.tabs button{border:1.5px solid var(--line);background:#fff;border-radius:999px;padding:9px 18px;
  font-weight:700;cursor:pointer;font-size:.92rem;color:var(--slate)}
.tabs button.active{background:var(--brand);border-color:var(--brand);color:#fff}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin-top:8px}
.chips button{border:1.5px solid var(--line);background:#fff;border-radius:999px;padding:5px 13px;
  font-weight:600;cursor:pointer;font-size:.85rem;color:var(--slate)}
.chips button:hover{border-color:var(--brand);color:var(--brand-deep)}
/* dynamic rows, stat cards, tables */
.field textarea{width:100%;padding:12px 14px;border:1.5px solid var(--line);border-radius:12px;
  font-size:1rem;font-family:inherit;min-height:170px;resize:vertical}
.field textarea:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px var(--brand-soft)}
.area-row{border:1.5px solid var(--line);border-radius:12px;padding:16px;margin-bottom:14px;background:#fcfefd}
.area-row .area-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px}
.area-row .area-head strong{font-size:.98rem}
.btn-small{background:var(--brand-soft);color:var(--brand-deep);border:none;border-radius:10px;
  padding:9px 16px;font-weight:700;cursor:pointer;font-size:.9rem}
.btn-small:hover{background:#d1fae5}
.btn-danger{background:#fef2f2;color:#b91c1c}
.btn-danger:hover{background:#fee2e2}
.stats{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:12px;margin-top:4px}
.stat{background:var(--brand-soft);border-radius:12px;padding:14px 10px;text-align:center}
.stat .num{font-size:1.4rem;font-weight:800;color:var(--brand-deep);line-height:1.2}
.stat .lab{font-size:.8rem;color:var(--muted);font-weight:700;margin-top:3px}
table.datatable{width:100%;border-collapse:collapse;margin-top:10px;font-size:.95rem}
table.datatable th,table.datatable td{border:1px solid var(--line);padding:8px 10px;text-align:right}
table.datatable th:first-child,table.datatable td:first-child{text-align:left}
table.datatable th{background:var(--brand-soft);text-align:right}
table.datatable th:first-child{text-align:left}
table.datatable tfoot td{font-weight:800;background:#f8fafc}
.scroll-x{overflow-x:auto}
.disclaimer{margin-top:20px;padding-top:14px;border-top:1px dashed var(--line);
  color:var(--muted);font-size:.85rem}
/* content sections */
.section{margin:40px 0}
.section h2{font-size:1.45rem;margin:0 0 14px;letter-spacing:-.01em}
.prose{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:26px}
.prose h3{margin:22px 0 8px;font-size:1.1rem}
.prose h3:first-child{margin-top:0}
.prose p,.prose li{color:#334155}
.prose code{background:var(--brand-soft);padding:1px 6px;border-radius:6px;font-size:.92em}
.formula{background:#f8fafc;border:1px solid var(--line);border-left:4px solid var(--brand);
  border-radius:10px;padding:14px 16px;margin:12px 0;font-size:.98rem}
.faq details{border:1px solid var(--line);border-radius:12px;padding:14px 16px;margin-bottom:10px;background:#fff}
.faq summary{font-weight:700;cursor:pointer}
/* footer */
.kit-network{margin-top:60px;background:linear-gradient(135deg,#ecfdf5 0%,#f0fdf4 100%);
  border-top:1px solid var(--line);padding:38px 0 42px}
.kit-network h2{font-size:1.25rem;margin:0 0 6px;letter-spacing:-.01em;color:var(--slate)}
.kit-network p{color:var(--muted);margin:0 0 18px;font-size:.95rem}
.kit-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:12px}
.kit-grid a{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;font-weight:700;
  color:var(--slate);display:flex;align-items:center;justify-content:space-between;gap:8px;
  transition:transform .25s ease,box-shadow .25s ease,border-color .25s ease}
.kit-grid a:hover{transform:translateY(-3px);box-shadow:0 12px 24px rgba(6,78,59,.13);border-color:#a7f3d0;
  color:var(--brand-deep);text-decoration:none}
.kit-grid a .arr{color:var(--brand);font-weight:800}
.site-footer{background:var(--slate);color:#cbd5e1;padding:40px 0;margin-top:0}
.site-footer .wrap{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:28px}
.site-footer h4{color:#fff;margin:0 0 12px;font-size:1rem}
.site-footer a{color:#cbd5e1;display:block;margin-bottom:8px;font-size:.93rem}
.site-footer p{font-size:.9rem;margin:0 0 10px}
.bottom-bar{border-top:1px solid #1e293b;margin-top:28px;padding-top:18px;font-size:.85rem;color:#94a3b8}
/* breadcrumbs */
.crumbs{font-size:.85rem;color:var(--muted);margin:18px 0 0}
.crumbs a{color:var(--muted)}
@media(max-width:760px){
  nav.main{display:none;position:absolute;top:100%;left:0;right:0;background:#fff;
    flex-direction:column;align-items:stretch;padding:10px 18px 18px;border-bottom:1px solid var(--line);
    box-shadow:0 24px 40px rgba(15,23,42,.14);max-height:calc(100vh - 62px);overflow-y:auto}
  nav.main.open{display:flex}
  nav.main>a{padding:13px 12px}
  .nav-drop-btn{width:100%;justify-content:space-between;padding:13px 12px}
  .nav-drop-panel{position:static;width:auto;max-width:none;box-shadow:none;border:none;border-radius:0;
    padding:2px 0 6px 12px;grid-template-columns:1fr;display:none;opacity:1;visibility:visible;transform:none;transition:none}
  .nav-drop.open .nav-drop-panel{display:grid}
  #navToggle{display:block}
  .hero h1{font-size:1.65rem}
  .field-row,.field-row3{grid-template-columns:1fr}
  .site-footer .wrap{grid-template-columns:1fr}
  .calculator{margin-top:-24px;padding:20px}
}
@media print{
  .site-header,.site-footer,.kit-network,.tool-hero,.crumbs,.section,.btn,.btn-small,.no-print{display:none !important}
  .calculator{box-shadow:none;border:none;margin:0;padding:0}
  body{background:#fff}
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms !important;animation-iteration-count:1 !important;transition-duration:.01ms !important}
  html{scroll-behavior:auto}
}