/* ========================================================
   ARC MEN Chemical (Siam Plasma Corp.) - Industrial Theme
   Brand: red logo + blue accent (matching catalog design)
   ======================================================== */

* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --red: #d32027;
  --red-dark: #a3171c;
  --red-soft: #fdecec;
  --blue: #1e3a6b;
  --blue-mid: #2c5599;
  --blue-light: #e8eef7;
  --orange: #e74907;          /* used in original product titles */
  --dark: #1a1f2e;
  --text: #2a2f3a;
  --text-light: #5e6573;
  --bg: #ffffff;
  --bg-soft: #f5f7fb;
  --bg-tint: #fafbfd;
  --border: #e1e6ee;
  --border-strong: #c5cdd9;
  --shadow: 0 2px 12px rgba(30, 58, 107, 0.08);
  --shadow-hover: 0 8px 24px rgba(211, 32, 39, 0.16);
  --radius: 4px;
  --max-width: 1180px;
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, "Segoe UI", "Helvetica Neue", "Noto Sans Thai", "Sarabun", "Microsoft JhengHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
}

a { color: var(--red); text-decoration: none; transition: color .2s; }
a:hover { color: var(--red-dark); }

img { max-width: 100%; height: auto; display: block; }

/* ============= Top Bar ============= */
.top-bar {
  background: var(--blue);
  color: #c8d4e8;
  font-size: 13px;
  padding: 8px 24px;
}
.top-bar-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
}
.top-bar a { color: #c8d4e8; }
.top-bar a:hover { color: #fff; }
.top-bar .info { display: flex; gap: 22px; flex-wrap: wrap; }
.top-bar .info span::before {
  display: inline-block;
  width: 18px;
  text-align: center;
  margin-right: 4px;
  opacity: .8;
}
.top-bar .tag {
  background: var(--red);
  color: #fff;
  padding: 2px 10px;
  border-radius: 2px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1px;
}

/* ============= Header ============= */
.site-header {
  background: #fff;
  border-bottom: 4px solid var(--red);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 8px rgba(0,0,0,.05);
}
.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}
.brand {
  display: flex;
  align-items: center;
  gap: 16px;
  text-decoration: none;
}
.brand img {
  height: 50px;
  width: auto;
}
.brand-text { line-height: 1.2; }
.brand-text strong {
  display: block;
  font-size: 15px;
  color: var(--blue);
  letter-spacing: 1px;
  font-weight: 800;
}
.brand-text span {
  font-size: 11px;
  color: var(--text-light);
  letter-spacing: 1.2px;
  text-transform: uppercase;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.main-nav a {
  padding: 10px 18px;
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
  border-radius: var(--radius);
  transition: all .2s;
  letter-spacing: .5px;
  text-transform: uppercase;
  position: relative;
}
.main-nav a:hover { background: var(--red-soft); color: var(--red); }
.main-nav a.active {
  background: var(--red);
  color: #fff;
}
.main-nav a.active:hover { background: var(--red-dark); color: #fff; }

/* ============= Hero ============= */
.hero {
  position: relative;
  background: linear-gradient(135deg, var(--blue) 0%, var(--dark) 100%);
  color: #fff;
  padding: 80px 24px 90px;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 60%;
  height: 100%;
  background: var(--red);
  transform: skewX(-12deg);
  transform-origin: top left;
  margin-left: -8%;
  opacity: .92;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 80% 30%, rgba(255,255,255,.08) 0%, transparent 40%);
}
.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 50px;
  align-items: center;
}
@media (max-width: 880px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero::before { width: 100%; transform: none; margin-left: 0; opacity: .85; }
}
.hero .est-line {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 4px;
  color: rgba(255,255,255,.95);
  text-transform: uppercase;
  margin-bottom: 20px;
  padding: 5px 14px;
  border: 1px solid rgba(255,255,255,.4);
  border-radius: 50px;
  font-weight: 600;
}
.hero h1 {
  font-size: clamp(30px, 5vw, 48px);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 22px;
  letter-spacing: -.5px;
  text-shadow: 0 2px 8px rgba(0,0,0,.2);
}
.hero p.lead {
  font-size: clamp(15px, 1.7vw, 17px);
  color: rgba(255,255,255,.95);
  margin-bottom: 30px;
  text-shadow: 0 1px 4px rgba(0,0,0,.25);
  max-width: 540px;
}
.hero .cta-row { display: flex; gap: 14px; flex-wrap: wrap; }

.hero-image {
  position: relative;
  display: flex;
  justify-content: center;
}
.hero-image img {
  max-width: 100%;
  border: 4px solid #fff;
  border-radius: var(--radius);
  box-shadow: 0 12px 40px rgba(0,0,0,.3);
  transform: rotate(-2deg);
}

.btn {
  display: inline-block;
  padding: 13px 28px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 1px;
  text-transform: uppercase;
  transition: all .2s;
  cursor: pointer;
  border: 2px solid transparent;
}
.btn-primary {
  background: #fff;
  color: var(--red);
}
.btn-primary:hover { background: var(--blue); color: #fff; }
.btn-secondary {
  background: transparent;
  color: #fff;
  border-color: rgba(255,255,255,.5);
}
.btn-secondary:hover { background: #fff; color: var(--blue); }

/* ============= Page Header ============= */
.page-header {
  background: linear-gradient(135deg, var(--blue) 0%, var(--blue-mid) 100%);
  color: #fff;
  padding: 50px 24px 45px;
  position: relative;
  overflow: hidden;
}
.page-header::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--red);
}
.page-header::after {
  content: "";
  position: absolute;
  top: 50%;
  right: -40px;
  width: 200px;
  height: 200px;
  background: var(--red);
  transform: translateY(-50%) rotate(45deg);
  opacity: .15;
}
.page-header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  position: relative;
  z-index: 2;
}
.breadcrumb {
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 12px;
  color: rgba(255,255,255,.7);
}
.breadcrumb a { color: rgba(255,255,255,.85); }
.breadcrumb a:hover { color: #fff; }
.breadcrumb .sep { margin: 0 8px; opacity: .5; }
.page-header h1 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 800;
  letter-spacing: -.3px;
}
.page-header p {
  margin-top: 8px;
  color: rgba(255,255,255,.9);
  font-size: 16px;
  max-width: 700px;
}

/* ============= Container ============= */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 70px 24px;
}
.container-narrow {
  max-width: 980px;
  margin: 0 auto;
  padding: 70px 24px;
}

section h2 {
  font-size: 30px;
  color: var(--blue);
  font-weight: 800;
  margin-bottom: 14px;
  letter-spacing: -.3px;
}
section h2.center { text-align: center; }
section .section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  color: var(--red);
  background: var(--red-soft);
  padding: 4px 14px;
  border-radius: 2px;
  margin-bottom: 12px;
}
section h3 {
  font-size: 22px;
  color: var(--blue);
  font-weight: 700;
  margin: 30px 0 14px;
}
section h4 {
  font-size: 16px;
  color: var(--orange);
  font-weight: 700;
  margin: 18px 0 8px;
  letter-spacing: .3px;
}

section p { margin-bottom: 14px; }

/* ============= Hero / Title separator ============= */
.divider {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 14px 0;
}
.divider::after {
  content: "";
  flex: 1;
  height: 2px;
  background: linear-gradient(90deg, var(--red) 0%, transparent 100%);
}

/* ============= Product Cards (Home + Products list) ============= */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 26px;
  margin-top: 36px;
}
.product-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform .25s, box-shadow .25s, border-color .25s;
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
}
.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--red);
  color: inherit;
}
.product-card-img {
  background: linear-gradient(135deg, var(--red-soft) 0%, var(--blue-light) 100%);
  height: 240px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  position: relative;
}
.product-card-img img {
  max-height: 100%;
  max-width: 100%;
  object-fit: contain;
}
.product-card-code {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--red);
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 1px;
  padding: 4px 9px;
  border-radius: 2px;
}
.product-card-body {
  padding: 22px;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.product-card-body h3 {
  margin: 0 0 6px;
  font-size: 17px;
  color: var(--blue);
  font-weight: 700;
}
.product-card-body p {
  font-size: 13px;
  color: var(--text-light);
  flex: 1;
  margin-bottom: 14px;
  line-height: 1.55;
}
.product-card-body .more {
  font-size: 12px;
  font-weight: 700;
  color: var(--red);
  letter-spacing: 1.5px;
  text-transform: uppercase;
}
.product-card-body .more::after { content: " →"; transition: margin .2s; }
.product-card:hover .more::after { margin-left: 6px; }

/* ============= Stats / Highlights row ============= */
.stats-bar {
  background: var(--blue);
  color: #fff;
  padding: 50px 24px;
  position: relative;
}
.stats-bar::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--red);
}
.stats-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 30px;
  text-align: center;
}
.stat .num {
  font-size: 40px;
  font-weight: 800;
  line-height: 1;
  margin-bottom: 8px;
  color: #fff;
  letter-spacing: -.5px;
}
.stat .num em { color: var(--red); font-style: normal; }
.stat .label {
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
  opacity: .85;
}

/* ============= About: split layout ============= */
.split {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 50px;
  align-items: start;
}
.split-equal {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
@media (max-width: 880px) {
  .split, .split-equal { grid-template-columns: 1fr; gap: 30px; }
}

.feature-list {
  list-style: none;
  margin: 16px 0;
  padding: 0;
}
.feature-list li {
  position: relative;
  padding: 10px 0 10px 36px;
  border-bottom: 1px dashed var(--border);
  font-size: 15px;
}
.feature-list li:last-child { border-bottom: none; }
.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  width: 22px;
  height: 22px;
  background: var(--red);
  border-radius: 2px;
  background-image:
    linear-gradient(45deg, transparent 35%, #fff 35% 40%, transparent 40%),
    linear-gradient(-45deg, transparent 55%, #fff 55% 65%, transparent 65%);
}

.numbered-list {
  list-style: none;
  margin: 16px 0;
  padding: 0;
  counter-reset: item;
}
.numbered-list li {
  position: relative;
  padding: 12px 0 12px 50px;
  counter-increment: item;
  border-bottom: 1px dashed var(--border);
  font-size: 14px;
  line-height: 1.6;
}
.numbered-list li::before {
  content: counter(item);
  position: absolute;
  left: 0;
  top: 11px;
  width: 32px;
  height: 32px;
  background: var(--blue);
  color: #fff;
  border-radius: 2px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 14px;
}
.numbered-list li:last-child { border-bottom: none; }

/* ============= Section variations ============= */
.section-soft { background: var(--bg-soft); }
.section-tint { background: linear-gradient(180deg, var(--bg-tint) 0%, #fff 100%); }
.section-dark { background: var(--blue); color: #d8e1ee; }
.section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }
.section-dark .section-tag { background: rgba(255,255,255,.15); color: #fff; }

/* ============= Product Detail (single-product page) ============= */
.product-hero {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 50px;
  align-items: start;
  margin-bottom: 50px;
}
@media (max-width: 880px) { .product-hero { grid-template-columns: 1fr; } }

.product-hero-img {
  background: linear-gradient(135deg, var(--red-soft) 0%, var(--blue-light) 100%);
  padding: 30px;
  border-radius: var(--radius);
  text-align: center;
}
.product-hero-img img {
  max-height: 400px;
  margin: 0 auto;
}

.product-hero-info .code {
  display: inline-block;
  background: var(--red);
  color: #fff;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 1.5px;
  border-radius: 2px;
  margin-bottom: 14px;
}
.product-hero-info h1 {
  font-size: 30px;
  color: var(--blue);
  margin-bottom: 6px;
  font-weight: 800;
}
.product-hero-info .subtitle-th {
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 18px;
  font-weight: 500;
}
.product-hero-info .summary {
  background: var(--bg-soft);
  border-left: 4px solid var(--red);
  padding: 16px 20px;
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 15px;
  color: var(--text);
  margin-bottom: 22px;
}

.benefits-table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.benefits-table tr td {
  padding: 12px 18px;
  font-size: 14px;
  border-bottom: 1px solid var(--border);
}
.benefits-table tr:last-child td { border-bottom: none; }
.benefits-table tr td:first-child {
  width: 50px;
  background: var(--blue);
  color: #fff;
  font-weight: 800;
  text-align: center;
  font-size: 13px;
}
.benefits-table tr:nth-child(even) td:not(:first-child) { background: var(--bg-tint); }

.product-features-img {
  margin: 30px 0;
  text-align: center;
  background: var(--bg-soft);
  padding: 20px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.product-features-img img {
  max-width: 100%;
  margin: 0 auto;
  border-radius: var(--radius);
}

.video-embed {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  border-radius: var(--radius);
  background: var(--blue);
  margin: 24px 0;
}
.video-embed iframe {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  border: none;
}

/* ============= Other Business Section ============= */
.other-biz-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
  margin-top: 30px;
}
.biz-item {
  background: #fff;
  border: 1px solid var(--border);
  border-left: 4px solid var(--blue);
  padding: 18px 22px;
  border-radius: 0 var(--radius) var(--radius) 0;
  transition: all .2s;
}
.biz-item:hover {
  border-left-color: var(--red);
  box-shadow: var(--shadow);
  transform: translateX(2px);
}
.biz-item h4 {
  margin: 0 0 4px;
  font-size: 14px;
  color: var(--blue);
}
.biz-item p {
  font-size: 13px;
  color: var(--text-light);
  margin: 0;
}

/* ============= Contact / Branches ============= */
.branches-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
  gap: 24px;
  margin-top: 36px;
}
.branch-card {
  background: #fff;
  border: 1px solid var(--border);
  border-top: 4px solid var(--red);
  border-radius: var(--radius);
  padding: 22px;
  transition: box-shadow .2s, transform .2s;
}
.branch-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}
.branch-card .branch-tag {
  display: inline-block;
  background: var(--red);
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  padding: 3px 10px;
  border-radius: 2px;
  margin-bottom: 10px;
}
.branch-card h3 {
  margin: 0 0 14px;
  font-size: 17px;
  color: var(--blue);
}
.branch-card .map-thumb {
  width: 100%;
  height: 200px;
  object-fit: contain;
  background: #fff;
  border-radius: var(--radius);
  margin-bottom: 14px;
  border: 1px solid var(--border);
  padding: 8px;
}
.branch-card .info {
  font-size: 13px;
  line-height: 1.7;
  color: var(--text);
}
.branch-card .info strong {
  color: var(--blue);
  display: inline-block;
  min-width: 50px;
}
.branch-card .addr {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 12px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--border);
  line-height: 1.55;
}

/* ============= Footer ============= */
.site-footer {
  background: var(--dark);
  color: #c0c8d4;
  padding: 60px 24px 26px;
  margin-top: 80px;
  border-top: 4px solid var(--red);
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr;
  gap: 40px;
}
@media (max-width: 768px) {
  .footer-inner { grid-template-columns: 1fr; gap: 30px; }
}
.footer-col h4 {
  color: #fff;
  font-size: 13px;
  margin-bottom: 16px;
  letter-spacing: 2px;
  text-transform: uppercase;
  border-bottom: 2px solid var(--red);
  padding-bottom: 8px;
  display: inline-block;
}
.footer-col p, .footer-col a {
  color: #b0b8c4;
  font-size: 13px;
  line-height: 1.8;
  display: block;
}
.footer-col a:hover { color: #fff; }
.footer-bottom {
  max-width: var(--max-width);
  margin: 40px auto 0;
  padding-top: 20px;
  border-top: 1px solid #353d4a;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 12px;
  color: #7a818d;
  letter-spacing: .5px;
}

/* ============= Mobile ============= */
.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  padding: 8px 12px;
  cursor: pointer;
  border-radius: 4px;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--red);
  margin: 4px 0;
}

@media (max-width: 880px) {
  .nav-toggle { display: block; }
  .main-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    padding-top: 14px;
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 12px 16px; }
}