/* ============================================================
   SK-Soft — Design tokens
   ============================================================ */
:root {
  --navy-950: #0c1638;
  --navy-900: #13285b;
  --blue-600: #1d56d8;
  --blue-400: #4aa2ff;
  --purple-500: #856bcc;
  --cyan-500: #00acc1;
  --ink-900: #101425;
  --ink-700: #3a4258;
  --ink-500: #64708a;
  --ink-300: #a2acc4;
  --surface-0: #ffffff;
  --surface-50: #f6f8fc;
  --surface-100: #eef1f9;
  --surface-line: #e3e8f3;
  --success: #00897b;
  --warning: #ffc107;

  --gradient-brand: linear-gradient(120deg, var(--navy-900) 0%, var(--blue-600) 55%, var(--blue-400) 100%);
  --gradient-brand-soft: linear-gradient(135deg, rgba(29, 86, 216, 0.10) 0%, rgba(74, 162, 255, 0.10) 100%);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 999px;

  --shadow-sm: 0 1px 2px rgba(16, 20, 37, 0.06), 0 1px 3px rgba(16, 20, 37, 0.08);
  --shadow-md: 0 8px 24px rgba(16, 20, 37, 0.08), 0 2px 8px rgba(16, 20, 37, 0.06);
  --shadow-lg: 0 24px 60px rgba(19, 40, 91, 0.16);

  --font-head: "Readex Pro", "Noto Sans Thai", "Inter", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans Thai", "Readex Pro", system-ui, sans-serif;

  --container: 1180px;
}

:root[data-lang="th"] {
  --font-head: "Noto Sans Thai", "Readex Pro", "Inter", system-ui, sans-serif;
  --font-body: "Noto Sans Thai", "Inter", "Readex Pro", system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink-900: #f2f4fa;
    --ink-700: #cfd6e8;
    --ink-500: #98a3c0;
    --ink-300: #5a6584;
    --surface-0: #0f1526;
    --surface-50: #131a30;
    --surface-100: #182038;
    --surface-line: #262f4c;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink-900);
  background: var(--surface-0);
  -webkit-font-smoothing: antialiased;
  line-height: 1.55;
}
h1, h2, h3, h4 { font-family: var(--font-head); font-weight: 600; line-height: 1.2; margin: 0; color: var(--ink-900); }
p { margin: 0; color: var(--ink-700); }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
button { font-family: inherit; cursor: pointer; }

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: 96px 0; }
.section--tight { padding: 64px 0; }
.section--alt { background: var(--surface-50); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--blue-600);
  background: var(--gradient-brand-soft);
  padding: 6px 14px;
  border-radius: var(--radius-full);
}

.section-head { max-width: 620px; margin-bottom: 48px; }
.section-head h2 { font-size: clamp(28px, 3.4vw, 38px); margin-top: 14px; }
.section-head p { font-size: 17px; margin-top: 14px; }
.section-head--center { margin-left: auto; margin-right: auto; text-align: center; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 15px;
  border: 1px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease, color 0.15s ease;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn--primary {
  background: var(--gradient-brand);
  color: #fff;
  box-shadow: 0 10px 24px rgba(29, 86, 216, 0.28);
}
.btn--primary:hover { box-shadow: 0 14px 30px rgba(29, 86, 216, 0.36); transform: translateY(-1px); }
.btn--ghost {
  background: transparent;
  color: var(--ink-900);
  border-color: var(--surface-line);
}
.btn--ghost:hover { background: var(--surface-100); }
.btn--on-dark {
  background: rgba(255,255,255,0.08);
  color: #fff;
  border-color: rgba(255,255,255,0.28);
  backdrop-filter: blur(6px);
}
.btn--on-dark:hover { background: rgba(255,255,255,0.16); }
.btn--block { width: 100%; }

/* ============================================================
   Header
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--surface-line);
}
@media (prefers-color-scheme: dark) {
  .site-header { background: rgba(15, 21, 38, 0.78); }
}
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-head); font-weight: 700; font-size: 19px; }
.brand__mark {
  width: 36px; height: 36px; border-radius: 10px;
  background: var(--gradient-brand);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 14px; font-weight: 700; letter-spacing: -0.02em;
  box-shadow: 0 6px 16px rgba(29, 86, 216, 0.35);
}
.brand__name span { color: var(--blue-600); }

.nav { display: flex; align-items: center; gap: 36px; }
.nav__links { display: flex; align-items: center; gap: 30px; }
.nav__links a { font-size: 15px; font-weight: 500; color: var(--ink-700); transition: color .15s ease; }
.nav__links a:hover { color: var(--blue-600); }
.nav__cta { display: flex; align-items: center; gap: 14px; }

.lang-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 44px; height: 38px; padding: 0 12px;
  border-radius: var(--radius-full);
  border: 1px solid var(--surface-line);
  background: var(--surface-0);
  font-family: var(--font-head);
  font-size: 13px; font-weight: 700; letter-spacing: 0.02em;
  color: var(--ink-700);
  transition: background .15s ease, border-color .15s ease;
}
.lang-toggle:hover { background: var(--surface-100); border-color: var(--blue-600); color: var(--blue-600); }
.nav__links-cta { display: none; }

.nav__toggle {
  display: none;
  width: 40px; height: 40px;
  border: 1px solid var(--surface-line);
  border-radius: var(--radius-sm);
  background: var(--surface-0);
  align-items: center; justify-content: center;
}
.nav__toggle span, .nav__toggle::before, .nav__toggle::after {
  content: ""; display: block; width: 18px; height: 2px; background: var(--ink-900); border-radius: 2px;
  position: relative; transition: transform .2s ease, opacity .2s ease;
}
.nav__toggle::before { position: absolute; transform: translateY(-6px); }
.nav__toggle::after { position: absolute; transform: translateY(6px); }
.nav__toggle.is-open span { opacity: 0; }
.nav__toggle.is-open::before { transform: rotate(45deg); }
.nav__toggle.is-open::after { transform: rotate(-45deg); }

/* ============================================================
   Hero
   ============================================================ */
.hero {
  position: relative;
  overflow: hidden;
  background-image: linear-gradient(120deg, rgba(12, 22, 56, 0.93) 0%, rgba(29, 86, 216, 0.90) 55%, rgba(74, 162, 255, 0.84) 100%), url("/img/hero-classroom.jpg");
  background-size: cover;
  background-position: center;
  color: #fff;
  padding: 108px 0 96px;
}
.hero::before {
  content: "";
  position: absolute;
  inset: -20% -10%;
  background:
    radial-gradient(circle at 15% 20%, rgba(74, 162, 255, 0.35), transparent 40%),
    radial-gradient(circle at 85% 10%, rgba(133, 107, 204, 0.35), transparent 45%),
    radial-gradient(circle at 75% 85%, rgba(0, 172, 193, 0.25), transparent 45%);
  pointer-events: none;
}
.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: center;
}
.hero__eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; letter-spacing: 0.03em;
  background: rgba(255,255,255,0.12); border: 1px solid rgba(255,255,255,0.22);
  padding: 7px 16px; border-radius: var(--radius-full); color: #dce6ff;
}
.hero h1 {
  font-size: clamp(34px, 4.6vw, 54px);
  margin-top: 20px;
  color: #fff;
  letter-spacing: -0.01em;
}
.hero h1 em { font-style: normal; background: linear-gradient(90deg, #9fd0ff, #d9c8ff); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero__tagline-th { font-size: 16px; color: #bcd0ff; margin-top: 14px; font-family: var(--font-head); }
.hero p.hero__lead { margin-top: 18px; font-size: 18px; color: #d7e0f8; max-width: 540px; }
.hero__actions { display: flex; gap: 14px; margin-top: 34px; flex-wrap: wrap; }
.hero__stats { display: flex; gap: 36px; margin-top: 52px; flex-wrap: wrap; }
.hero__stat strong { display: block; font-family: var(--font-head); font-size: 26px; color: #fff; }
.hero__stat span { font-size: 13px; color: #b9c7ea; }

.hero__panel {
  position: relative;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: var(--radius-lg);
  padding: 22px;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-lg);
}
.hero__panel-card {
  background: var(--surface-0);
  border-radius: var(--radius-md);
  padding: 22px;
  color: var(--ink-900);
}
.hero__panel-row { display: flex; align-items: center; justify-content: space-between; margin-bottom: 18px; }
.hero__panel-title { font-family: var(--font-head); font-weight: 600; font-size: 15px; }
.hero__panel-badge { font-size: 11px; font-weight: 700; color: var(--success); background: rgba(0,137,123,0.12); padding: 4px 10px; border-radius: var(--radius-full); }
.hero__panel-metric { display: flex; align-items: baseline; gap: 8px; margin-bottom: 4px; }
.hero__panel-metric strong { font-size: 30px; font-family: var(--font-head); }
.hero__panel-metric span { font-size: 13px; color: var(--ink-500); }
.hero__bars { display: flex; align-items: flex-end; gap: 6px; height: 64px; margin: 18px 0; }
.hero__bars i { flex: 1; border-radius: 6px 6px 0 0; background: var(--gradient-brand); opacity: 0.85; }
.hero__panel-list { display: flex; flex-direction: column; gap: 10px; margin-top: 6px; }
.hero__panel-list li { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--ink-700); }
.hero__panel-list i.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--blue-600); flex: none; }
.hero__float {
  position: absolute; right: -18px; bottom: -18px;
  background: var(--surface-0); color: var(--ink-900);
  border-radius: var(--radius-md); box-shadow: var(--shadow-lg);
  padding: 14px 18px; display: flex; align-items: center; gap: 10px;
  font-size: 13px; font-weight: 600;
}
.hero__float .icon-wrap { background: var(--gradient-brand-soft); color: var(--blue-600); }

/* ============================================================
   Logo strip
   ============================================================ */
.logo-strip { padding: 40px 0; border-bottom: 1px solid var(--surface-line); }
.logo-strip__label { text-align: center; font-size: 13px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-500); margin-bottom: 22px; }
.logo-strip__row { display: flex; justify-content: center; align-items: center; gap: 48px; flex-wrap: wrap; }
.logo-strip__item { font-family: var(--font-head); font-weight: 600; font-size: 16px; color: var(--ink-500); opacity: 0.85; display: flex; align-items: center; gap: 8px; }

/* ============================================================
   Icon wrap
   ============================================================ */
.icon-wrap {
  width: 44px; height: 44px;
  display: flex; align-items: center; justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--gradient-brand-soft);
  color: var(--blue-600);
  flex: none;
}
.icon-wrap svg { width: 22px; height: 22px; }
.icon-wrap--cyan { background: rgba(0, 172, 193, 0.12); color: var(--cyan-500); }
.icon-wrap--purple { background: rgba(133, 107, 204, 0.12); color: var(--purple-500); }

/* ============================================================
   Products
   ============================================================ */
.products-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
.product-card {
  border: 1px solid var(--surface-line);
  border-radius: var(--radius-lg);
  padding: 36px;
  background: var(--surface-0);
  box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease;
  display: flex; flex-direction: column; height: 100%;
}
.product-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.product-card__top { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; }
.product-card__tag {
  font-size: 12px; font-weight: 700; letter-spacing: 0.03em; text-transform: uppercase;
  padding: 5px 12px; border-radius: var(--radius-full);
}
.product-card__tag--web { color: var(--blue-600); background: rgba(29,86,216,0.10); }
.product-card__tag--mobile { color: var(--cyan-500); background: rgba(0,172,193,0.10); }
.product-card h3 { font-size: 24px; margin-top: 20px; }
.product-card__desc { margin-top: 10px; font-size: 15.5px; }
.product-card__meta { margin-top: 16px; font-size: 13px; color: var(--ink-500); }
.product-card__list { margin-top: 22px; display: flex; flex-direction: column; gap: 12px; flex: 1; }
.product-card__list li { display: flex; gap: 10px; align-items: flex-start; font-size: 14.5px; color: var(--ink-700); }
.product-card__list svg { flex: none; width: 18px; height: 18px; margin-top: 2px; color: var(--success); }
.product-card__footer { margin-top: 26px; display: flex; gap: 12px; }

/* ============================================================
   Features
   ============================================================ */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature-card {
  padding: 28px 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--surface-line);
  background: var(--surface-0);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.feature-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: transparent; }
.feature-card h4 { font-size: 16.5px; margin-top: 18px; }
.feature-card p { font-size: 14px; margin-top: 8px; }

/* ============================================================
   About / story
   ============================================================ */
.about-grid { display: grid; grid-template-columns: 0.95fr 1.05fr; gap: 64px; align-items: center; }
.about-copy p + p { margin-top: 16px; }
.about-copy p { font-size: 16px; }
.about-stats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-top: 32px; }
.about-stat { padding: 20px; border-radius: var(--radius-md); background: var(--surface-50); border: 1px solid var(--surface-line); }
.about-stat strong { display: block; font-family: var(--font-head); font-size: 28px; background: var(--gradient-brand); -webkit-background-clip: text; background-clip: text; color: transparent; }
.about-stat span { font-size: 13.5px; color: var(--ink-500); }

.timeline { display: flex; flex-direction: column; gap: 0; border-left: 2px solid var(--surface-line); padding-left: 28px; }
.timeline__item { position: relative; padding-bottom: 34px; }
.timeline__item:last-child { padding-bottom: 0; }
.timeline__item::before {
  content: ""; position: absolute; left: -34px; top: 4px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--gradient-brand); box-shadow: 0 0 0 4px var(--surface-0);
}
.timeline__year { font-family: var(--font-head); font-weight: 700; color: var(--blue-600); font-size: 14px; }
.timeline__item h4 { margin-top: 4px; font-size: 16.5px; }
.timeline__item p { margin-top: 6px; font-size: 14.5px; }

/* ============================================================
   Gallery
   ============================================================ */
.gallery-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.gallery-card {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 3 / 4;
  box-shadow: var(--shadow-sm);
}
.gallery-card img {
  width: 100%; height: 100%; object-fit: cover; display: block;
  transition: transform .5s ease;
}
.gallery-card:hover img { transform: scale(1.06); }
.gallery-card__caption {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: 20px 16px 16px;
  background: linear-gradient(0deg, rgba(12,22,56,0.88) 0%, rgba(12,22,56,0.0) 100%);
  color: #fff; font-family: var(--font-head); font-weight: 600; font-size: 14.5px;
}

/* ============================================================
   CTA banner
   ============================================================ */
.cta-banner {
  border-radius: var(--radius-lg);
  background-image: linear-gradient(120deg, rgba(12, 22, 56, 0.91) 0%, rgba(29, 86, 216, 0.87) 55%, rgba(74, 162, 255, 0.80) 100%), url("/img/cta-tech.jpg");
  background-size: cover;
  background-position: center;
  padding: 64px;
  display: flex; align-items: center; justify-content: space-between;
  gap: 32px; flex-wrap: wrap;
  position: relative; overflow: hidden;
  color: #fff;
}
.cta-banner::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(circle at 85% 20%, rgba(255,255,255,0.14), transparent 45%);
}
.cta-banner__text { position: relative; max-width: 520px; }
.cta-banner__text h2 { color: #fff; font-size: clamp(24px, 3vw, 32px); }
.cta-banner__text p { color: #dbe4fb; margin-top: 12px; font-size: 16px; }
.cta-banner__actions { position: relative; display: flex; gap: 14px; flex-wrap: wrap; }

/* ============================================================
   Contact
   ============================================================ */
.contact-grid { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 56px; }
.contact-info__item { display: flex; gap: 16px; padding: 18px 0; border-bottom: 1px solid var(--surface-line); }
.contact-info__item:first-child { padding-top: 0; }
.contact-info__item h4 { font-size: 15px; }
.contact-info__item p { font-size: 14.5px; margin-top: 4px; }

.contact-form { background: var(--surface-50); border: 1px solid var(--surface-line); border-radius: var(--radius-lg); padding: 36px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: 13.5px; font-weight: 600; margin-bottom: 7px; color: var(--ink-700); }
.field input, .field select, .field textarea {
  width: 100%; padding: 12px 14px; border-radius: var(--radius-sm);
  border: 1px solid var(--surface-line); background: var(--surface-0);
  font-family: inherit; font-size: 14.5px; color: var(--ink-900);
  transition: border-color .15s ease, box-shadow .15s ease;
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--blue-600); box-shadow: 0 0 0 3px rgba(29,86,216,0.14);
}
.field textarea { resize: vertical; min-height: 110px; }
.form-note { font-size: 12.5px; color: var(--ink-500); margin-top: 12px; }

/* ============================================================
   Footer
   ============================================================ */
.site-footer { background: var(--navy-950); color: #b9c3df; padding: 64px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 40px; }
.footer-brand p { color: #94a1c4; font-size: 14px; margin-top: 14px; max-width: 280px; }
.footer-col h5 { color: #fff; font-size: 14px; font-family: var(--font-head); margin-bottom: 16px; }
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col a { font-size: 14px; color: #a7b1d1; transition: color .15s ease; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  margin-top: 48px; padding-top: 24px; border-top: 1px solid rgba(255,255,255,0.08);
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
  font-size: 13px; color: #7c88ac;
}
.footer-social { display: flex; gap: 12px; }
.footer-social a {
  width: 36px; height: 36px; border-radius: 50%; border: 1px solid rgba(255,255,255,0.14);
  display: flex; align-items: center; justify-content: center;
}
.footer-social a:hover { background: rgba(255,255,255,0.08); }

/* ============================================================
   Reveal animation
   ============================================================ */
[data-reveal] { opacity: 0; transform: translateY(16px); transition: opacity .6s ease, transform .6s ease; }
[data-reveal].is-visible { opacity: 1; transform: translateY(0); }

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 980px) {
  .hero__inner { grid-template-columns: 1fr; }
  .hero__panel { max-width: 460px; }
  .about-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
  .nav__links, .nav__cta .btn--ghost, .nav__cta .btn--primary { display: none; }
  .nav__toggle { display: flex; }
  .site-header.is-open .nav__links {
    display: flex; flex-direction: column; position: absolute; top: 76px; left: 0; right: 0;
    background: var(--surface-0); padding: 20px 24px; gap: 18px; border-bottom: 1px solid var(--surface-line);
  }
  .site-header.is-open .nav__links-cta { display: block; margin-top: 4px; }
  .section { padding: 64px 0; }
  .features-grid { grid-template-columns: 1fr; }
  .gallery-grid { grid-template-columns: 1fr 1fr; gap: 14px; }
  .form-row { grid-template-columns: 1fr; }
  .cta-banner { padding: 40px 28px; flex-direction: column; text-align: center; }
  .cta-banner__actions { justify-content: center; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .hero { padding-top: 88px; }
  .hero__stats { gap: 24px; }
}