:root{
  --navy:#0b2545; --navy-2:#123a63; --blue:#1668b0; --blue-light:#3b96e0;
  --teal:#1f8a70; --gold:#c99a3f;
  --ink:#16202e; --body:#4a5568; --line:#e3e8ef;
  --bg:#ffffff; --bg-alt:#f5f8fc;
  --radius:16px; --shadow:0 8px 30px rgba(11,37,69,.08);
  --shadow-lg:0 18px 50px rgba(11,37,69,.14);
  --max:1200px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'IBM Plex Sans Thai',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  color:var(--body);background:var(--bg);line-height:1.75;font-size:16.5px;font-weight:400;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
}
h1,h2,h3,h4{font-family:'IBM Plex Sans Thai',sans-serif;color:var(--ink);line-height:1.28;
  font-weight:600;letter-spacing:-0.015em}
h1{font-size:clamp(1.9rem,4vw,3rem)}
h2{font-size:clamp(1.5rem,3vw,2.2rem);margin-bottom:1rem}
h3{font-size:1.15rem}
a{color:var(--blue);text-decoration:none;transition:.2s}
a:hover{color:var(--navy)}
img{max-width:100%;display:block}
.container{max-width:var(--max);margin:0 auto;padding:0 1.25rem}
.container.narrow{max-width:820px}
.center{text-align:center}
.light{color:#fff !important}
.muted{color:#8a93a1}

/* ---------- topbar + nav ---------- */
.topbar{background:var(--navy);color:rgba(255,255,255,.85);font-size:.85rem}
.topbar-inner{display:flex;gap:1.5rem;align-items:center;padding:.5rem 1.25rem;flex-wrap:wrap}
.topbar a{color:rgba(255,255,255,.9)}
.topbar a:hover{color:#fff}
.navbar{position:sticky;top:0;z-index:100;background:rgba(255,255,255,.96);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);transition:.3s}
.navbar.scrolled{box-shadow:0 4px 20px rgba(11,37,69,.09)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;padding:.6rem 1.25rem;gap:1rem}
.brand{display:flex;align-items:center;gap:.75rem;color:var(--ink)}
.brand img{height:50px;width:auto;object-fit:contain}
.brand-text{display:flex;flex-direction:column;line-height:1.25}
.brand-text strong{font-family:'IBM Plex Sans Thai';font-size:1.05rem;color:var(--navy)}
.brand-text small{font-size:.72rem;color:var(--body)}
.nav-links{display:flex;gap:.35rem;list-style:none;align-items:center}
.nav-links a{
  display:block;padding:.55rem .9rem;border-radius:10px;font-weight:500;
  color:var(--ink);font-family:'IBM Plex Sans Thai';font-size:.95rem;
}
.nav-links a:hover{background:var(--bg-alt);color:var(--blue)}
.nav-links a.active{color:var(--blue);background:#eaf2fb}
.nav-links a.btn-nav{background:var(--blue);color:#fff}
.nav-links a.btn-nav:hover{background:var(--navy);color:#fff}
.nav-toggle{display:none;background:none;border:0;font-size:1.6rem;color:var(--navy);cursor:pointer}

/* ---------- buttons ---------- */
.btn{
  display:inline-block;padding:.85rem 1.7rem;border-radius:999px;font-family:'IBM Plex Sans Thai';
  font-weight:500;font-size:.95rem;letter-spacing:.005em;border:1.5px solid transparent;cursor:pointer;transition:.25s;
  text-align:center;
}
.btn-primary{background:var(--blue);color:#fff;box-shadow:0 6px 18px rgba(22,104,176,.28)}
.btn-primary:hover{background:var(--navy);color:#fff;transform:translateY(-2px);box-shadow:0 10px 26px rgba(11,37,69,.3)}
.btn-outline{border-color:var(--blue);color:var(--blue);background:transparent}
.btn-outline:hover{background:var(--blue);color:#fff}
.btn-outline-light{border-color:rgba(255,255,255,.7);color:#fff;background:transparent}
.btn-outline-light:hover{background:#fff;color:var(--navy)}
.btn-white{background:#fff;color:var(--navy)}
.btn-white:hover{background:var(--bg-alt);color:var(--navy)}
.btn-line{background:#06c755;color:#fff}
.btn-line:hover{background:#05a648;color:#fff}
.btn-block{display:block;width:100%}

/* ---------- hero slider ---------- */
.hero{position:relative;height:min(78vh,620px);min-height:440px;overflow:hidden;background:var(--navy)}
.hero-slide{
  position:absolute;inset:0;background-size:cover;background-position:center;
  opacity:0;transition:opacity 1s ease;display:grid;align-content:center;
}
.hero-slide.active{opacity:1}
.hero-slide.active .hero-content{animation:heroIn .9s ease both}
.hero-overlay{position:absolute;inset:0;background:linear-gradient(95deg,rgba(6,18,36,.72) 0%,rgba(6,18,36,.45) 38%,rgba(6,18,36,.12) 62%,rgba(6,18,36,0) 100%)}
.hero .container{width:100%}
.hero-content{position:relative;color:#fff;max-width:760px}
@keyframes heroIn{from{opacity:0;transform:translateY(28px)}to{opacity:1;transform:none}}
.hero-badge{
  display:inline-block;background:rgba(255,255,255,.15);border:1px solid rgba(255,255,255,.3);
  padding:.35rem 1rem;border-radius:999px;font-size:.85rem;margin-bottom:1rem;backdrop-filter:blur(4px);
}
.hero-title{color:#fff;font-size:clamp(1.9rem,4.6vw,3.4rem);margin-bottom:.9rem;
  letter-spacing:-0.02em;font-weight:600;text-shadow:0 2px 24px rgba(0,0,0,.45)}
.hero-subtitle{font-size:clamp(1rem,1.8vw,1.18rem);color:rgba(255,255,255,.92);margin-bottom:1.9rem;
  max-width:620px;font-weight:300;text-shadow:0 1px 12px rgba(0,0,0,.4)}
.hero-actions{display:flex;gap:.8rem;flex-wrap:wrap}
.hero-arrow{
  position:absolute;top:50%;transform:translateY(-50%);z-index:5;
  background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.3);color:#fff;
  width:48px;height:48px;border-radius:50%;font-size:1.8rem;line-height:1;cursor:pointer;
  backdrop-filter:blur(6px);transition:.2s;
}
.hero-arrow:hover{background:rgba(255,255,255,.32)}
.hero-arrow.prev{left:1.5rem}
.hero-arrow.next{right:1.5rem}
.hero-dots{position:absolute;bottom:1.6rem;left:50%;transform:translateX(-50%);display:flex;gap:.5rem;z-index:5}
.hero-dots .dot{width:34px;height:5px;border-radius:99px;border:0;background:rgba(255,255,255,.4);cursor:pointer;transition:.3s}
.hero-dots .dot.active{background:#fff;width:52px}

/* ---------- sections ---------- */
.section{padding:clamp(3rem,7vw,5.5rem) 0}
.section-alt{background:var(--bg-alt)}
.section-dark{background:linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 100%);color:rgba(255,255,255,.85)}
.section-dark h2,.section-dark h3{color:#fff}
.eyebrow{
  display:inline-block;font-family:'IBM Plex Sans Thai';font-size:.8rem;font-weight:600;letter-spacing:.12em;
  text-transform:uppercase;color:var(--blue);margin-bottom:.7rem;
}
.eyebrow.center{display:block;text-align:center}
.eyebrow.light{color:var(--blue-light)}
.section h2.center{margin-bottom:2.5rem}
.lead{font-size:1.02rem;margin-bottom:1rem}

.page-header{background:linear-gradient(135deg,var(--navy) 0%,var(--navy-2) 100%);color:rgba(255,255,255,.85);padding:3.5rem 0 3rem;text-align:center}
.page-header h1{color:#fff;margin-bottom:.6rem}
.page-header p{max-width:720px;margin:0 auto}

/* ---------- about ---------- */
.about-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:3rem;align-items:start}
.about-cards{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
.stat-card{
  background:var(--bg-alt);border:1px solid var(--line);border-radius:var(--radius);
  padding:1.5rem 1.25rem;transition:.25s;
}
.stat-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);background:#fff}
.stat-card strong{display:block;font-family:'IBM Plex Sans Thai';font-size:1.5rem;color:var(--blue);margin-bottom:.35rem}
.stat-card span{font-size:.88rem;line-height:1.55;display:block}

/* ---------- categories ---------- */
.category-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:1.75rem}
.category-card{
  background:#fff;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);
  transition:.3s;display:block;color:inherit;
}
.category-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg)}
.category-img{height:220px;background-size:cover;background-position:center;background-color:#0d1f36}
.category-body{padding:1.5rem}
.category-body h3{margin-bottom:.6rem;color:var(--navy)}
.category-body p{font-size:.92rem;margin-bottom:.9rem}
.link-more{font-family:'IBM Plex Sans Thai';font-weight:500;color:var(--blue);font-size:.92rem}

/* ---------- products ---------- */
.filter-chips{display:flex;gap:.6rem;flex-wrap:wrap;margin-bottom:2.5rem;justify-content:center}
.chip{
  padding:.5rem 1.2rem;border-radius:999px;border:1.5px solid var(--line);
  background:#fff;color:var(--body);font-family:'IBM Plex Sans Thai';font-size:.9rem;
}
.chip:hover{border-color:var(--blue);color:var(--blue)}
.chip.active{background:var(--blue);border-color:var(--blue);color:#fff}
.product-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:1.5rem}
.product-card{
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
  transition:.3s;color:inherit;display:flex;flex-direction:column;
}
.product-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:transparent}
.product-img{height:210px;background-size:cover;background-position:center;background-color:#0d1f36}
.product-body{padding:1.15rem;display:flex;flex-direction:column;gap:.5rem;flex:1}
.product-body h3{font-size:1.02rem;color:var(--navy)}
.product-body p{font-size:.88rem;flex:1}
.price{font-family:'IBM Plex Sans Thai';font-weight:600;color:var(--blue)}

/* ---------- installation ---------- */
.service-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:1.25rem;margin-top:2.5rem}
.service-card{
  background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.14);
  border-radius:var(--radius);padding:1.5rem;transition:.25s;
}
.service-card:hover{background:rgba(255,255,255,.13);transform:translateY(-4px)}
.service-card p{font-size:.94rem;color:rgba(255,255,255,.88)}
.service-num{
  display:inline-block;font-family:'IBM Plex Sans Thai';font-size:1.6rem;font-weight:700;
  color:var(--blue-light);margin-bottom:.5rem;
}
.install-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:1.5rem}
.install-card{
  background:#fff;border:1px solid var(--line);border-left:4px solid var(--blue);
  border-radius:12px;padding:1.5rem;transition:.25s;
}
.install-card:hover{box-shadow:var(--shadow);transform:translateX(4px)}
.install-card .service-num{color:var(--blue);font-size:1.3rem}
.install-card h3{font-size:1rem;font-weight:500;line-height:1.6}
.note-box{
  margin-top:2.5rem;background:var(--bg-alt);border-radius:var(--radius);
  padding:2rem;border:1px solid var(--line);
}

/* ---------- promotions ---------- */
.promo-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:1.5rem}
.promo-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.promo-img{height:200px;background-size:cover;background-position:center}
.promo-body{padding:1.5rem}
.promo-body h3{margin-bottom:.6rem;color:var(--navy)}
.promo-body p{font-size:.93rem;margin-bottom:.8rem}

/* ---------- portfolio ---------- */
.client-badges{display:flex;flex-wrap:wrap;gap:.75rem;justify-content:center}
.client-badge{
  background:#fff;border:1px solid var(--line);border-radius:999px;
  padding:.6rem 1.3rem;font-family:'IBM Plex Sans Thai';font-size:.9rem;color:var(--navy);
  box-shadow:0 2px 8px rgba(11,37,69,.05);transition:.2s;
}
.client-badge:hover{border-color:var(--blue);color:var(--blue);transform:translateY(-2px)}
.group-title{margin:2.5rem 0 1.25rem;padding-bottom:.6rem;border-bottom:2px solid var(--line)}
.group-title:first-child{margin-top:0}
.portfolio-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:1.25rem}
.portfolio-card{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:1.4rem;
  border-top:3px solid var(--gold);transition:.25s;
}
.portfolio-card:hover{box-shadow:var(--shadow);transform:translateY(-4px)}
.portfolio-card h3{font-size:1rem;color:var(--navy)}
.portfolio-card p{font-size:.85rem;margin-top:.35rem}

/* ---------- FAQ ---------- */
.faq-item{
  background:#fff;border:1px solid var(--line);border-radius:12px;
  padding:1.1rem 1.35rem;margin-bottom:.8rem;transition:.2s;
}
.faq-item[open]{box-shadow:var(--shadow);border-color:var(--blue)}
.faq-item summary{
  font-family:'IBM Plex Sans Thai';font-weight:500;color:var(--navy);cursor:pointer;
  list-style:none;position:relative;padding-right:2rem;
}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:'+';position:absolute;right:0;font-size:1.4rem;color:var(--blue);line-height:1}
.faq-item[open] summary::after{content:'−'}
.faq-item p{margin-top:.8rem;font-size:.94rem}

/* ---------- product detail ---------- */
.breadcrumb{font-size:.87rem;color:var(--body);margin-bottom:2rem}
.breadcrumb a{color:var(--body)}
.breadcrumb a:hover{color:var(--blue)}
.detail-grid{display:grid;grid-template-columns:1fr 1fr;gap:3rem;margin-bottom:3rem}
.detail-main-img{
  height:440px;border-radius:var(--radius);background-size:cover;background-position:center;
  background-color:#0d1f36;box-shadow:var(--shadow);
}
.detail-thumbs{display:flex;gap:.6rem;margin-top:.8rem;flex-wrap:wrap}
.thumb{
  width:78px;height:66px;border-radius:10px;border:2px solid var(--line);
  background-size:cover;background-position:center;cursor:pointer;transition:.2s;
}
.thumb.active,.thumb:hover{border-color:var(--blue)}
.detail-info h1{margin-bottom:.3rem}
.detail-en{color:var(--body);font-size:1rem;margin-bottom:1rem}
.price-lg{display:block;font-family:'IBM Plex Sans Thai';font-size:1.5rem;font-weight:600;color:var(--blue);margin-bottom:1.2rem}
.detail-short{font-size:1rem;margin-bottom:1.8rem}
.detail-actions{display:flex;gap:.7rem;flex-wrap:wrap}
.detail-tabs{border-top:1px solid var(--line);padding-top:2.5rem}
.detail-tabs h2{margin-top:1.5rem}
.detail-tabs h2:first-child{margin-top:0}
.detail-tabs p{margin-bottom:.9rem}
.spec-table{width:100%;border-collapse:collapse;margin-top:1rem;font-size:.94rem}
.spec-table th,.spec-table td{border:1px solid var(--line);padding:.8rem 1rem;text-align:left}
.spec-table th{background:var(--bg-alt);width:34%;font-family:'IBM Plex Sans Thai';font-weight:500;color:var(--navy)}
.related{margin-top:3.5rem;border-top:1px solid var(--line);padding-top:2.5rem}

/* ---------- contact ---------- */
.contact-grid{display:grid;grid-template-columns:1.3fr .7fr;gap:2.5rem;align-items:start}
.contact-form{display:flex;flex-direction:column;gap:1rem;margin-top:1.25rem}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
.contact-form label,.contact-info strong{font-family:'IBM Plex Sans Thai';font-weight:500;color:var(--ink);font-size:.92rem}
.contact-form label{display:flex;flex-direction:column;gap:.4rem}
.contact-form input,.contact-form select,.contact-form textarea{
  font-family:'IBM Plex Sans Thai';font-size:.95rem;padding:.8rem 1rem;border:1.5px solid var(--line);
  border-radius:10px;background:#fff;color:var(--ink);transition:.2s;width:100%;
}
.contact-form input:focus,.contact-form select:focus,.contact-form textarea:focus{
  outline:none;border-color:var(--blue);box-shadow:0 0 0 3px rgba(22,104,176,.12);
}
.contact-form textarea{resize:vertical}
.alert-success{
  background:#e8f7ee;border:1px solid #a7dcbc;color:#186c3b;
  padding:1rem 1.25rem;border-radius:12px;margin-bottom:1.25rem;
}
.contact-info{background:var(--bg-alt);border:1px solid var(--line);border-radius:var(--radius);padding:1.75rem}
.info-item{margin-bottom:1.35rem}
.info-item p{font-size:.93rem;margin-top:.25rem}
.line-box{text-align:center;border-top:1px solid var(--line);padding-top:1.35rem}
.qr-img{width:150px;margin:.8rem auto;border-radius:10px}
.map-wrap{border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}

/* ---------- CTA ---------- */
.cta-band{background:linear-gradient(120deg,var(--blue) 0%,var(--navy) 100%);color:#fff;padding:3.5rem 0}
.cta-inner{display:flex;justify-content:space-between;align-items:center;gap:2rem;flex-wrap:wrap}
.cta-band h2{color:#fff;margin-bottom:.4rem}
.cta-band p{color:rgba(255,255,255,.88)}
.cta-actions{display:flex;gap:.8rem;flex-wrap:wrap}

/* ---------- footer ---------- */
.footer{background:#081a30;color:rgba(255,255,255,.72);padding:3.5rem 0 0;font-size:.92rem}
.footer-grid{display:grid;grid-template-columns:1.4fr .7fr 1.1fr .9fr;gap:2.5rem;padding-bottom:2.5rem}
.footer h3{color:#fff;font-size:1rem;margin-bottom:1rem}
.footer a{color:rgba(255,255,255,.72)}
.footer a:hover{color:#fff}
.footer-logo{width:215px;height:auto;background:#fff;border-radius:12px;padding:14px 16px;margin-bottom:1.1rem}
.footer-about{font-size:.9rem;line-height:1.7}
.footer-links{list-style:none;display:flex;flex-direction:column;gap:.5rem}
.footer-contact{font-style:normal;line-height:1.9}
.footer-qr img{width:130px;border-radius:10px;background:#fff;padding:6px}
.footer-qr p{margin-top:.5rem;font-size:.85rem}
.footer-bottom{border-top:1px solid rgba(255,255,255,.1);padding:1.25rem 0;font-size:.85rem;text-align:center}

/* ---------- floating buttons ---------- */
.float-line,.float-phone{
  position:fixed;right:1.25rem;z-index:90;width:56px;height:56px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;color:#fff;
  font-family:'IBM Plex Sans Thai';font-size:.75rem;font-weight:600;box-shadow:var(--shadow-lg);transition:.25s;
}
.float-line{bottom:5.5rem;background:#06c755}
.float-phone{bottom:1.25rem;background:var(--blue)}
.float-line:hover,.float-phone:hover{transform:scale(1.08);color:#fff}

/* ---------- responsive ---------- */
@media (max-width:960px){
  .about-grid,.detail-grid,.contact-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media (max-width:760px){
  .hide-mobile{display:none}
  .nav-toggle{display:block}
  .nav-links{
    position:absolute;top:100%;left:0;right:0;background:#fff;flex-direction:column;
    align-items:stretch;gap:0;padding:.5rem;border-bottom:1px solid var(--line);
    box-shadow:var(--shadow);display:none;
  }
  .nav-links.open{display:flex}
  .nav-links a{padding:.85rem 1rem;border-radius:8px}
  .hero{height:auto;min-height:0;padding:0}
  /* the photos carry their dark area on the left; cover-cropping a narrow
     screen would push it off and leave the text sitting over bright metal */
  .hero-slide{position:relative;height:auto;min-height:480px;display:none;opacity:1;
    background-position:left center}
  .hero-slide.active{display:grid}
  .hero-overlay{background:linear-gradient(180deg,rgba(6,18,36,.78) 0%,rgba(6,18,36,.66) 50%,rgba(6,18,36,.84) 100%)}
  /* swipe + dots cover navigation on touch; arrows would overlap the text */
  .hero-arrow{display:none}
  .about-cards,.form-row{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr;text-align:center}
  .footer-links{align-items:center}
  .footer-logo,.footer-qr img{margin-left:auto;margin-right:auto}
  .cta-inner{flex-direction:column;text-align:center}
  .cta-actions{justify-content:center}
  .detail-main-img{height:300px}
}