:root{
  --navy:#0b2447;--blue:#1448b8;--blue-soft:#eaf1ff;--accent:#d9480f;--accent-d:#b93c0a;--accent-soft:#fff3e8;
  --ink:#1b2a41;--mute:#5b6b82;--line:#e2e8f0;--bg:#fff;--bg2:#f5f8fc;--ok:#0f8a5f;--warn:#b45309;
  --r:16px;--shadow:0 10px 30px rgba(11,36,71,.08);--max:1120px
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;font-family:'Noto Sans Thai','Sarabun',system-ui,-apple-system,'Segoe UI',sans-serif;color:var(--ink);background:var(--bg);line-height:1.75;font-size:17px}
img,svg{max-width:100%;height:auto}
a{color:var(--blue);text-underline-offset:3px}
a:hover{color:var(--accent)}
.wrap{max-width:var(--max);margin:0 auto;padding:0 20px}
.skip{position:absolute;left:-999px}.skip:focus{left:10px;top:10px;background:#fff;padding:8px 12px;z-index:99}

/* header */
.hdr{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.94);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.hdr .wrap{display:flex;align-items:center;gap:20px;height:68px}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--navy);font-weight:800;font-size:19px;line-height:1.1}
.logo small{display:block;font-weight:500;font-size:11.5px;color:var(--mute);letter-spacing:.2px}
.logo-mark{width:38px;height:38px;border-radius:11px;background:linear-gradient(135deg,var(--accent),#ff8a3d);display:grid;place-items:center;flex:none}
.nav{display:flex;gap:4px;margin-left:auto;align-items:center}
.nav a{padding:8px 12px;border-radius:10px;text-decoration:none;color:var(--ink);font-size:15px;font-weight:500}
.nav a:hover,.nav a[aria-current=page]{background:var(--blue-soft);color:var(--blue)}
.nav .btn{margin-left:8px;color:#fff}
.nav .btn:hover{background:var(--accent-d);color:#fff}
.burger{display:none;margin-left:auto;background:none;border:1px solid var(--line);border-radius:10px;width:44px;height:44px;cursor:pointer;align-items:center;justify-content:center}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;background:var(--accent);color:#fff;text-decoration:none;font-weight:700;padding:12px 22px;border-radius:12px;border:0;cursor:pointer;font:inherit;font-weight:700;box-shadow:0 6px 16px rgba(217,72,15,.28);transition:.18s transform,.18s background}
.btn:hover{background:var(--accent-d);color:#fff;transform:translateY(-1px)}
.btn.lg{padding:15px 30px;font-size:18px;border-radius:14px}
.btn.ghost{background:#fff;color:var(--blue);border:1.5px solid var(--blue);box-shadow:none}
.btn.ghost:hover{background:var(--blue-soft);color:var(--blue)}

/* hero */
.hero{background:radial-gradient(1000px 420px at 85% -10%,#dbe8ff 0,transparent 60%),linear-gradient(180deg,#fff7ed 0,#fff 100%);padding:56px 0 40px;overflow:hidden}
.hero .wrap{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center}
.kicker{display:inline-block;background:var(--accent-soft);color:var(--accent-d);font-weight:700;font-size:14px;padding:5px 14px;border-radius:999px;margin-bottom:14px}
h1{font-size:clamp(28px,4.4vw,46px);line-height:1.25;margin:0 0 16px;color:var(--navy);font-weight:800;letter-spacing:-.2px}
.lead{font-size:19px;color:#34455f;margin:0 0 24px}
.hero-cta{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.hero small{display:block;margin-top:14px;color:var(--mute);font-size:13.5px}
.cardviz{position:relative;max-width:440px;margin-left:auto}
.cardviz svg{width:100%;filter:drop-shadow(0 24px 40px rgba(11,36,71,.22))}
.chip-float{position:absolute;background:#fff;border-radius:14px;padding:10px 14px;box-shadow:var(--shadow);font-size:14px;font-weight:700;color:var(--navy);display:flex;gap:8px;align-items:center}
.chip-float i{font-style:normal;color:var(--ok)}
.cf1{left:-14px;bottom:36px}.cf2{right:-6px;top:-8px}

/* stats */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin:-6px 0 0}
.stat{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:18px 16px;text-align:center;box-shadow:var(--shadow)}
.stat b{display:block;font-size:26px;color:var(--navy);line-height:1.2}
.stat span{font-size:14px;color:var(--mute)}

/* sections */
section{padding:56px 0}
.alt{background:var(--bg2)}
h2{font-size:clamp(23px,3vw,32px);line-height:1.35;color:var(--navy);margin:0 0 12px;font-weight:800}
h3{font-size:20px;color:var(--navy);margin:26px 0 8px}
.sec-sub{color:var(--mute);margin:0 0 30px;max-width:720px}
.grid{display:grid;gap:18px}
.g3{grid-template-columns:repeat(3,1fr)}.g2{grid-template-columns:repeat(2,1fr)}.g4{grid-template-columns:repeat(4,1fr)}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:24px;box-shadow:0 2px 8px rgba(11,36,71,.04)}
.card h3{margin:12px 0 6px;font-size:18.5px}
.card p{margin:0;color:#3d4f68;font-size:15.5px}
.ico{width:48px;height:48px;border-radius:13px;background:var(--blue-soft);display:grid;place-items:center}
.ico svg{width:26px;height:26px;stroke:var(--blue);fill:none;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.steps{counter-reset:s;display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.step{position:relative;background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:22px 20px 20px}
.step:before{counter-increment:s;content:counter(s);position:absolute;top:-16px;left:18px;width:34px;height:34px;border-radius:50%;background:var(--accent);color:#fff;font-weight:800;display:grid;place-items:center}
.step h3{margin:8px 0 4px;font-size:17.5px}.step p{margin:0;font-size:15px;color:#3d4f68}

/* article */
.crumbs{font-size:14px;color:var(--mute);padding:18px 0 0}
.crumbs a{color:var(--mute)}
.page-hero{background:linear-gradient(180deg,#fff7ed,#fff);padding:10px 0 28px;border-bottom:1px solid var(--line)}
.meta{font-size:14px;color:var(--mute);margin-top:8px}
.layout{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:40px;padding:36px 0 56px}
.prose{min-width:0}
.prose h2{margin-top:40px;padding-top:6px;font-size:clamp(22px,2.6vw,28px)}
.prose h2:first-child{margin-top:0}
.prose p{margin:0 0 16px}
.prose ul,.prose ol{padding-left:22px;margin:0 0 18px}
.prose li{margin-bottom:6px}
.toc{background:var(--bg2);border:1px solid var(--line);border-radius:var(--r);padding:16px 20px;margin:0 0 28px;font-size:15.5px}
.toc b{display:block;margin-bottom:6px;color:var(--navy)}
.toc ol{margin:0;padding-left:20px}
.side{position:sticky;top:90px;align-self:start;display:grid;gap:16px}
.sidecta{background:linear-gradient(160deg,var(--navy),#16407f);color:#fff;border-radius:var(--r);padding:24px}
.sidecta b{font-size:19px;display:block;margin-bottom:6px}
.sidecta p{margin:0 0 16px;font-size:14.5px;color:#d6e2f7}
.sidecta .btn{width:100%}
.sidebox{border:1px solid var(--line);border-radius:var(--r);padding:18px 20px;font-size:15px;background:#fff}
.sidebox b{display:block;color:var(--navy);margin-bottom:8px}
.sidebox ul{list-style:none;margin:0;padding:0}.sidebox li{padding:6px 0;border-bottom:1px dashed var(--line)}.sidebox li:last-child{border:0}
.sidebox a{text-decoration:none}
.note,.warn,.tip{border-radius:14px;padding:16px 18px;margin:20px 0;font-size:15.5px}
.note{background:var(--blue-soft);border-left:4px solid var(--blue)}
.warn{background:#fff7e6;border-left:4px solid var(--warn)}
.tip{background:#ebfaf3;border-left:4px solid var(--ok)}
.note p,.warn p,.tip p{margin:0}
table{width:100%;border-collapse:collapse;margin:18px 0 24px;font-size:15.5px;background:#fff;border-radius:12px;overflow:hidden;border:1px solid var(--line)}
th,td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--navy);color:#fff;font-weight:700;font-size:14.5px}
tr:last-child td{border-bottom:0}
td.y{color:var(--ok);font-weight:700}
.tw{overflow-x:auto;-webkit-overflow-scrolling:touch}
.tw table{min-width:560px}
.pc{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin:18px 0}
.pc>div{border-radius:14px;padding:18px 20px;border:1px solid var(--line)}
.pc h3{margin:0 0 8px;font-size:18px}
.pc ul{margin:0;padding-left:20px}
.pc .pro{background:#f0fbf6;border-color:#bfe8d4}.pc .con{background:#fff6ee;border-color:#f7d3b4}

/* cta band */
.ctaband{background:linear-gradient(120deg,var(--navy),#1a4a9c);color:#fff;border-radius:22px;padding:34px 36px;display:flex;gap:24px;align-items:center;justify-content:space-between;margin:34px 0}
.ctaband h2,.ctaband h3{color:#fff;margin:0 0 6px;font-size:24px}
.ctaband p{margin:0;color:#d6e2f7;font-size:15.5px}
.ctaband .btn{white-space:nowrap}

/* faq */
details.faq{background:#fff;border:1px solid var(--line);border-radius:14px;margin:0 0 12px;overflow:hidden}
details.faq summary{cursor:pointer;padding:16px 52px 16px 20px;font-weight:700;color:var(--navy);list-style:none;position:relative}
details.faq summary::-webkit-details-marker{display:none}
details.faq summary:after{content:"+";position:absolute;right:20px;top:50%;transform:translateY(-50%);font-size:24px;color:var(--accent);transition:.2s}
details.faq[open] summary:after{content:"–"}
details.faq .a{padding:0 20px 18px;color:#34455f}
details.faq .a p{margin:0 0 10px}

/* calculator */
.calc{background:#fff;border:1px solid var(--line);border-radius:20px;box-shadow:var(--shadow);overflow:hidden}
.calc-h{background:var(--navy);color:#fff;padding:16px 24px;font-weight:700;font-size:18px}
.calc-b{display:grid;grid-template-columns:1fr 1fr;gap:0}
.calc-in,.calc-out{padding:24px}
.calc-out{background:var(--bg2);border-left:1px solid var(--line)}
.f{margin-bottom:16px}
.f label{display:block;font-weight:600;font-size:14.5px;margin-bottom:6px;color:var(--navy)}
.f input,.f select{width:100%;padding:12px 14px;border:1.5px solid #cbd5e1;border-radius:11px;font:inherit;font-size:16px;background:#fff;color:var(--ink)}
.f input:focus,.f select:focus{outline:0;border-color:var(--blue);box-shadow:0 0 0 3px rgba(20,72,184,.15)}
.f small{color:var(--mute);font-size:13px}
.res{display:flex;justify-content:space-between;gap:12px;padding:10px 0;border-bottom:1px dashed #cbd5e1;font-size:15.5px}
.res b{color:var(--navy);text-align:right}
.res.big{font-size:18px;border-bottom:0;padding-top:14px}.res.big b{font-size:26px;color:var(--accent-d)}
.seg{display:flex;background:#fff;border:1px solid var(--line);border-radius:12px;padding:4px;margin-bottom:16px;gap:4px}
.seg button{flex:1;border:0;background:none;padding:9px 6px;border-radius:9px;font:inherit;font-size:14.5px;font-weight:600;color:var(--mute);cursor:pointer}
.seg button.on{background:var(--blue);color:#fff}
.hint{font-size:13.5px;color:var(--mute);margin-top:12px}

/* footer */
.ftr{background:var(--navy);color:#c7d5ee;padding:48px 0 90px;font-size:15px}
.ftr a{color:#c7d5ee;text-decoration:none}.ftr a:hover{color:#fff;text-decoration:underline}
.fg{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:30px}
.ftr h4{color:#fff;margin:0 0 10px;font-size:16px}
.ftr ul{list-style:none;margin:0;padding:0}.ftr li{padding:4px 0}
.disc{border-top:1px solid #29467a;margin-top:30px;padding-top:20px;font-size:13.5px;line-height:1.7;color:#a9bbdb}

/* sticky mobile cta */
.mcta{display:none;position:fixed;left:0;right:0;bottom:0;z-index:60;background:#fff;border-top:1px solid var(--line);padding:10px 14px;box-shadow:0 -6px 20px rgba(0,0,0,.08)}
.mcta .btn{width:100%}

@media(max-width:900px){
  .hero .wrap{grid-template-columns:1fr}.cardviz{margin:10px auto 0;max-width:380px}
  .g3,.g4{grid-template-columns:repeat(2,1fr)}.steps{grid-template-columns:repeat(2,1fr);gap:26px 18px}
  .stats{grid-template-columns:repeat(2,1fr)}
  .layout{grid-template-columns:minmax(0,1fr)}.side{position:static}
  .fg{grid-template-columns:1fr 1fr}
  .calc-b{grid-template-columns:1fr}.calc-out{border-left:0;border-top:1px solid var(--line)}
}
@media(max-width:768px){
  body{font-size:16.5px}
  .burger{display:flex}
  .nav{display:none;position:absolute;left:0;right:0;top:68px;background:#fff;border-bottom:1px solid var(--line);flex-direction:column;align-items:stretch;padding:10px 16px 16px;box-shadow:var(--shadow)}
  .nav.open{display:flex}.nav a{padding:12px}.nav .btn{margin:8px 0 0}
  .mcta{display:block}
  .ctaband{flex-direction:column;align-items:flex-start;padding:26px 22px}
  .pc{grid-template-columns:1fr}
  section{padding:42px 0}
}
@media(max-width:640px){
  .g2,.g3,.g4{grid-template-columns:1fr}.steps{grid-template-columns:1fr}
  .stat b{font-size:22px}.cf1{left:0}.cf2{right:0}
  .hero{padding:36px 0 28px}.lead{font-size:17.5px}
  .btn.lg{width:100%}.hero-cta .btn{width:100%}
  .fg{grid-template-columns:1fr}
}
@media(max-width:400px){
  .wrap{padding:0 16px}.stats{gap:10px}.stat{padding:14px 8px}.logo small{display:none}
}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}