/* ============================================================
   28 SINE ENGINEERING — Stylesheet
   Theme: Deep construction-green + blueprint/technical-drawing motif
   ============================================================ */

:root{
  --forest-950:#0A2419;
  --forest-900:#0F3226;
  --forest-800:#154634;
  --green-700:#1E6B45;
  --green-600:#237C50;
  --green-500:#2F9E63;
  --green-300:#8FD3AC;
  --amber-500:#F2A73B;
  --concrete-50:#FAFAF6;
  --concrete-100:#F2F0E8;
  --concrete-200:#E5E2D6;
  --steel-600:#5B6660;
  --ink-900:#0E1A15;
  --white:#FFFFFF;

  --font-display:'Kanit', sans-serif;
  --font-body:'Sarabun', sans-serif;

  --container:1180px;
}

*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }
body{
  margin:0;
  font-family:var(--font-body);
  color:var(--ink-900);
  background:var(--concrete-50);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
img{ max-width:100%; display:block; }
a{ color:inherit; text-decoration:none; }
h1,h2,h3,h4{
  font-family:var(--font-display);
  margin:0 0 .5em;
  line-height:1.2;
  color:var(--forest-950);
}
p{ margin:0 0 1em; color:var(--steel-600); }
.container{
  width:100%;
  max-width:var(--container);
  margin:0 auto;
  padding:0 24px;
}
section{ padding:88px 0; }
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-display);
  font-size:13px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--green-600);
  font-weight:600;
  margin-bottom:16px;
}
.eyebrow::before{
  content:"";
  width:22px; height:2px;
  background:var(--amber-500);
}
.btn{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-display);
  font-weight:500;
  font-size:15px;
  padding:14px 28px;
  border-radius:2px;
  border:1.5px solid transparent;
  cursor:pointer;
  transition:.2s ease;
  letter-spacing:.02em;
}
.btn-primary{
  background:var(--amber-500);
  color:var(--ink-900);
}
.btn-primary:hover{ background:#e2952a; transform:translateY(-1px); }
.btn-ghost{
  border-color:rgba(255,255,255,.4);
  color:var(--white);
}
.btn-ghost:hover{ background:rgba(255,255,255,.1); }
.btn-outline{
  border-color:var(--forest-900);
  color:var(--forest-900);
}
.btn-outline:hover{ background:var(--forest-900); color:var(--white); }

/* ---------------- Dimension-line divider (signature motif) --------------- */
.dim-line{
  display:flex;
  align-items:center;
  gap:14px;
  color:var(--steel-600);
  font-family:var(--font-display);
  font-size:12px;
  letter-spacing:.12em;
  text-transform:uppercase;
  margin:8px 0 40px;
}
.dim-line::before,.dim-line::after{
  content:"";
  flex:1;
  height:1px;
  background:repeating-linear-gradient(90deg,var(--green-500) 0 6px,transparent 6px 10px);
}
.dim-line span{ white-space:nowrap; }

/* ---------------- Corner brackets (technical-drawing frame) -------------- */
.blueprint-frame{
  position:relative;
}
.blueprint-frame::before,.blueprint-frame::after{
  content:"";
  position:absolute;
  width:34px; height:34px;
  border:2px solid var(--amber-500);
  z-index:2;
}
.blueprint-frame::before{ top:-10px; left:-10px; border-right:none; border-bottom:none; }
.blueprint-frame::after{ bottom:-10px; right:-10px; border-left:none; border-top:none; }

/* ================= HEADER / NAV ================= */
header.site-header{
  position:sticky; top:0; z-index:100;
  background:var(--forest-950);
  border-bottom:1px solid rgba(255,255,255,.08);
}
.nav-wrap{
  display:flex; align-items:center; justify-content:space-between;
  padding:16px 0;
}
.logo{
  display:flex; flex-direction:column; line-height:1;
  color:var(--white);
}
.logo .mark{
  font-family:var(--font-display);
  font-weight:700;
  font-size:22px;
  letter-spacing:.02em;
}
.logo .mark b{ color:var(--amber-500); }
.logo .sub{
  font-size:10px;
  letter-spacing:.28em;
  color:var(--green-300);
  margin-top:3px;
}
nav.main-nav ul{
  list-style:none; display:flex; gap:34px; margin:0; padding:0;
}
nav.main-nav a{
  font-family:var(--font-display);
  font-size:15px;
  color:rgba(255,255,255,.82);
  position:relative;
  padding:6px 0;
  transition:.2s;
}
nav.main-nav a:hover, nav.main-nav a.active{ color:var(--white); }
nav.main-nav a.active::after{
  content:"";
  position:absolute; left:0; bottom:0;
  width:100%; height:2px;
  background:var(--amber-500);
}
.nav-actions{ display:flex; align-items:center; gap:18px; }
.nav-phone{
  display:flex; flex-direction:column;
  color:var(--white); font-family:var(--font-display);
  font-size:14px; text-align:right;
}
.nav-phone small{ color:var(--green-300); font-size:11px; letter-spacing:.08em; }
.nav-toggle{
  display:none;
  background:none; border:none; cursor:pointer;
  width:34px; height:28px; position:relative;
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after{
  content:""; position:absolute; left:0; width:100%; height:2px; background:var(--white);
}
.nav-toggle span{ top:13px; }
.nav-toggle span::before{ top:-9px; }
.nav-toggle span::after{ top:9px; }

/* ================= HERO ================= */
.hero{
  position:relative;
  min-height:640px;
  display:flex; align-items:flex-end;
  background:linear-gradient(180deg, rgba(10,36,25,.55) 0%, rgba(10,36,25,.88) 78%, var(--forest-950) 100%),
             url('https://images.unsplash.com/photo-1541888946425-d81bb19240f5?auto=format&fit=crop&w=1800&q=80') center/cover no-repeat;
  color:var(--white);
}
.hero-inner{
  padding-bottom:72px;
  max-width:760px;
}
.hero h1{
  color:var(--white);
  font-size:clamp(34px,5vw,58px);
  font-weight:600;
  margin-bottom:20px;
}
.hero h1 em{ font-style:normal; color:var(--amber-500); }
.hero p.lead{
  color:rgba(255,255,255,.86);
  font-size:18px;
  max-width:560px;
  margin-bottom:32px;
}
.hero-actions{ display:flex; gap:16px; flex-wrap:wrap; }
.hero-coords{
  position:absolute; right:24px; top:120px;
  writing-mode:vertical-rl;
  font-family:var(--font-display);
  font-size:12px; letter-spacing:.2em;
  color:rgba(255,255,255,.55);
  display:flex; align-items:center; gap:10px;
}
.hero-coords::after{ content:""; width:1px; height:70px; background:rgba(255,255,255,.35); }

/* ================= STATS STRIP ================= */
.stats-strip{
  background:var(--forest-900);
  color:var(--white);
  padding:0;
}
.stats-grid{
  display:grid; grid-template-columns:repeat(4,1fr);
}
.stat{
  padding:34px 24px;
  border-right:1px solid rgba(255,255,255,.1);
  text-align:center;
}
.stat:last-child{ border-right:none; }
.stat .num{
  font-family:var(--font-display);
  font-size:34px; font-weight:600; color:var(--green-300);
}
.stat .label{ font-size:13px; color:rgba(255,255,255,.7); margin-top:4px; }

/* ================= SERVICES ================= */
.section-head{
  max-width:640px; margin-bottom:52px;
}
.services-grid{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:2px;
  background:var(--concrete-200);
  border:1px solid var(--concrete-200);
}
.service-card{
  background:var(--white);
  padding:34px 30px;
  transition:.25s;
  position:relative;
}
.service-card:hover{ background:var(--forest-950); }
.service-card:hover h3, .service-card:hover p{ color:var(--white); }
.service-card:hover .service-idx{ color:var(--amber-500); }
.service-idx{
  font-family:var(--font-display);
  font-size:13px; color:var(--green-500);
  letter-spacing:.1em;
  margin-bottom:18px; display:block;
}
.service-card h3{ font-size:19px; margin-bottom:10px; }
.service-card p{ font-size:14.5px; margin-bottom:0; }

/* ================= PROCESS ================= */
.process-strip{
  background:var(--concrete-100);
}
.process-grid{
  display:grid; grid-template-columns:repeat(4,1fr); gap:0;
  counter-reset:step;
  position:relative;
}
.process-grid::before{
  content:"";
  position:absolute; top:22px; left:6%; right:6%; height:1px;
  background:repeating-linear-gradient(90deg,var(--green-500) 0 8px,transparent 8px 14px);
  z-index:0;
}
.process-step{ position:relative; padding:0 20px; z-index:1; }
.process-step .num{
  width:46px; height:46px; border-radius:50%;
  background:var(--forest-950); color:var(--white);
  display:flex; align-items:center; justify-content:center;
  font-family:var(--font-display); font-weight:600;
  margin-bottom:20px; border:3px solid var(--concrete-100);
}
.process-step h4{ font-size:17px; }
.process-step p{ font-size:14px; }

/* ================= PROJECT TYPES / GALLERY ================= */
.gallery-grid{
  display:grid;
  grid-template-columns:1.3fr 1fr 1fr;
  grid-template-rows:220px 220px;
  gap:14px;
}
.gallery-item{
  position:relative; overflow:hidden; border-radius:2px;
}
.gallery-item:first-child{ grid-row:span 2; }
.gallery-item img{
  width:100%; height:100%; object-fit:cover;
  transition:transform .4s ease;
}
.gallery-item:hover img{ transform:scale(1.06); }
.gallery-item .cap{
  position:absolute; left:0; bottom:0; right:0;
  padding:16px;
  background:linear-gradient(180deg,transparent,rgba(10,36,25,.9));
  color:var(--white);
  font-family:var(--font-display);
  font-size:14px;
}

/* ================= WHY US ================= */
.why-block{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:60px;
  align-items:center;
}
.why-img{ position:relative; }
.why-list{ list-style:none; margin:0; padding:0; }
.why-list li{
  display:flex; gap:16px;
  padding:18px 0;
  border-bottom:1px solid var(--concrete-200);
}
.why-list li:first-child{ padding-top:0; }
.why-num{
  font-family:var(--font-display);
  font-size:13px; color:var(--amber-500); font-weight:600;
  min-width:28px;
}
.why-list h4{ font-size:16.5px; margin-bottom:4px; }
.why-list p{ font-size:14px; margin:0; }

/* ================= CTA BAND ================= */
.cta-band{
  background:var(--forest-950);
  color:var(--white);
  text-align:center;
  position:relative;
  overflow:hidden;
}
.cta-band::before{
  content:"";
  position:absolute; inset:0;
  background-image:linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size:44px 44px;
  opacity:.5;
}
.cta-band .container{ position:relative; }
.cta-band h2{ color:var(--white); font-size:clamp(26px,4vw,38px); }
.cta-band p{ color:rgba(255,255,255,.75); max-width:520px; margin:0 auto 30px; }
.cta-actions{ display:flex; gap:16px; justify-content:center; flex-wrap:wrap; }

/* ================= PAGE HEADER (inner pages) ================= */
.page-hero{
  background:var(--forest-950);
  color:var(--white);
  padding:120px 0 70px;
  position:relative;
  overflow:hidden;
}
.page-hero::after{
  content:"";
  position:absolute; right:-60px; top:-60px;
  width:280px; height:280px;
  border:1px solid rgba(255,255,255,.12);
  border-radius:50%;
}
.page-hero .eyebrow{ color:var(--green-300); }
.page-hero h1{ color:var(--white); font-size:clamp(30px,4.4vw,46px); margin-bottom:14px; }
.page-hero p{ color:rgba(255,255,255,.75); max-width:540px; }
.crumb{
  font-family:var(--font-display); font-size:13px;
  color:rgba(255,255,255,.55); margin-bottom:18px;
}
.crumb b{ color:var(--amber-500); font-weight:500; }

/* ================= ABOUT PAGE ================= */
.split{
  display:grid; grid-template-columns:1fr 1fr; gap:64px; align-items:center;
}
.split.reverse .split-img{ order:2; }
.split-img{ position:relative; }
.value-grid{
  display:grid; grid-template-columns:repeat(2,1fr); gap:24px;
}
.value-card{
  background:var(--white);
  border:1px solid var(--concrete-200);
  padding:28px;
  border-top:3px solid var(--green-500);
}
.value-card h4{ font-size:17px; }
.value-card p{ font-size:14px; margin:0; }

.timeline{
  border-left:2px solid var(--concrete-200);
  margin-left:12px;
}
.timeline-item{
  position:relative;
  padding:0 0 40px 36px;
}
.timeline-item:last-child{ padding-bottom:0; }
.timeline-item::before{
  content:"";
  position:absolute; left:-7px; top:2px;
  width:12px; height:12px; border-radius:50%;
  background:var(--amber-500);
  border:2px solid var(--forest-950);
}
.timeline-item h4{ font-size:16px; margin-bottom:6px; }
.timeline-item p{ font-size:14px; margin:0; }

/* ================= CONTACT PAGE ================= */
.contact-grid{
  display:grid;
  grid-template-columns:.9fr 1.1fr;
  gap:0;
  border:1px solid var(--concrete-200);
}
.contact-info{
  background:var(--forest-950);
  color:var(--white);
  padding:52px 44px;
}
.contact-info h3{ color:var(--white); font-size:20px; }
.contact-list{ list-style:none; margin:28px 0 0; padding:0; }
.contact-list li{
  display:flex; gap:16px;
  padding:18px 0;
  border-top:1px solid rgba(255,255,255,.12);
}
.contact-list li:first-child{ border-top:none; }
.ico{
  width:38px; height:38px; flex:none;
  border:1px solid rgba(255,255,255,.3);
  border-radius:50%;
  display:flex; align-items:center; justify-content:center;
  font-size:16px;
}
.contact-list .label{ font-size:12px; color:var(--green-300); letter-spacing:.06em; margin-bottom:3px;}
.contact-list .value{ font-size:15px; color:var(--white); font-family:var(--font-display); font-weight:400; }
.map-wrap{ position:relative; min-height:420px; background:var(--concrete-200); }
.map-wrap iframe{ width:100%; height:100%; min-height:420px; border:0; filter:grayscale(15%); }

.contact-form-wrap{
  padding:52px 44px;
  background:var(--concrete-50);
}
.form-row{ display:grid; grid-template-columns:1fr 1fr; gap:18px; }
.field{ margin-bottom:20px; }
.field label{
  display:block; font-family:var(--font-display); font-size:13px;
  color:var(--forest-900); margin-bottom:8px; letter-spacing:.02em;
}
.field input, .field textarea, .field select{
  width:100%; padding:13px 14px;
  border:1px solid var(--concrete-200);
  background:var(--white);
  font-family:var(--font-body); font-size:15px;
  border-radius:2px;
  transition:.2s;
}
.field input:focus, .field textarea:focus, .field select:focus{
  outline:none; border-color:var(--green-500);
  box-shadow:0 0 0 3px rgba(47,158,99,.15);
}
.field textarea{ resize:vertical; min-height:130px; }
.form-note{ font-size:13px; color:var(--steel-600); margin-top:10px; }

/* ================= PRIVACY PAGE ================= */
.policy-wrap{
  max-width:820px; margin:0 auto;
}
.policy-wrap h2{
  font-size:22px; margin-top:44px;
  padding-top:20px; border-top:1px solid var(--concrete-200);
}
.policy-wrap h2:first-of-type{ border-top:none; padding-top:0; margin-top:0; }
.policy-wrap ul{ color:var(--steel-600); padding-left:20px; }
.policy-wrap li{ margin-bottom:8px; }
.updated-badge{
  display:inline-flex; align-items:center; gap:8px;
  font-family:var(--font-display); font-size:12px;
  color:var(--green-600); background:var(--concrete-100);
  padding:8px 16px; border-radius:20px; margin-bottom:30px;
}

/* ================= FOOTER ================= */
footer.site-footer{
  background:var(--forest-950);
  color:rgba(255,255,255,.72);
  padding:70px 0 0;
}
.footer-grid{
  display:grid; grid-template-columns:1.4fr 1fr 1fr 1.2fr;
  gap:40px;
  padding-bottom:50px;
  border-bottom:1px solid rgba(255,255,255,.1);
}
.footer-grid h5{
  font-family:var(--font-display); color:var(--white);
  font-size:14px; letter-spacing:.08em; text-transform:uppercase;
  margin-bottom:20px;
}
.footer-grid p, .footer-grid a{ font-size:14px; color:rgba(255,255,255,.65); }
.footer-grid ul{ list-style:none; padding:0; margin:0; }
.footer-grid li{ margin-bottom:12px; }
.footer-grid a:hover{ color:var(--amber-500); }
.footer-logo .mark{ font-family:var(--font-display); font-size:24px; color:var(--white); font-weight:700; }
.footer-logo .mark b{ color:var(--amber-500); }
.footer-bottom{
  display:flex; justify-content:space-between; align-items:center;
  padding:24px 0; font-size:13px; color:rgba(255,255,255,.5);
  flex-wrap:wrap; gap:10px;
}
.footer-bottom a{ color:rgba(255,255,255,.5); }
.footer-bottom a:hover{ color:var(--white); }

/* ================= RESPONSIVE ================= */
@media(max-width:960px){
  .services-grid{ grid-template-columns:repeat(2,1fr); }
  .why-block, .split{ grid-template-columns:1fr; gap:36px; }
  .split.reverse .split-img{ order:0; }
  .process-grid{ grid-template-columns:repeat(2,1fr); row-gap:40px; }
  .process-grid::before{ display:none; }
  .gallery-grid{ grid-template-columns:1fr 1fr; grid-template-rows:180px 180px 180px; }
  .gallery-item:first-child{ grid-row:span 1; grid-column:span 2; }
  .stats-grid{ grid-template-columns:repeat(2,1fr); }
  .stat{ border-bottom:1px solid rgba(255,255,255,.1); }
  .footer-grid{ grid-template-columns:1fr 1fr; }
  .contact-grid{ grid-template-columns:1fr; }
  .form-row{ grid-template-columns:1fr; }
}
@media(max-width:760px){
  nav.main-nav{
    position:fixed; inset:64px 0 0 0;
    background:var(--forest-950);
    padding:30px 24px;
    transform:translateX(100%);
    transition:.3s ease;
  }
  nav.main-nav.open{ transform:translateX(0); }
  nav.main-nav ul{ flex-direction:column; gap:0; }
  nav.main-nav li{ border-bottom:1px solid rgba(255,255,255,.08); }
  nav.main-nav a{ display:block; padding:16px 0; }
  .nav-toggle{ display:block; }
  .nav-phone{ display:none; }
  .services-grid{ grid-template-columns:1fr; }
  .value-grid{ grid-template-columns:1fr; }
  .footer-grid{ grid-template-columns:1fr; }
  .hero-coords{ display:none; }
  section{ padding:60px 0; }
  .hero{ min-height:560px; }
}