/* ============================================================
   OSTIAX — International Site Design System (Dark Tech)
   Palette: deep navy base, cyan/teal neon accents
   ============================================================ */

:root {
  --bg: #070d18;
  --bg-2: #0b1524;
  --panel: rgba(16, 30, 50, 0.72);
  --panel-solid: #101e32;
  --panel-2: #12233a;
  --line: rgba(34, 211, 238, 0.16);
  --line-strong: rgba(34, 211, 238, 0.38);
  --cy: #22d3ee;
  --cy-2: #0ea5e9;
  --teal: #2dd4bf;
  --txt: #e8f1fa;
  --mut: #94a8be;
  --mut-2: #6b8098;
  --grad: linear-gradient(92deg, #22d3ee 0%, #2dd4bf 100%);
  --grad-soft: linear-gradient(135deg, rgba(34, 211, 238, 0.16), rgba(45, 212, 191, 0.05));
  --shadow: 0 18px 50px rgba(2, 8, 20, 0.55);
  --glow: 0 0 24px rgba(34, 211, 238, 0.25);
  --radius: 18px;
  --nav-h: 68px;
  --font: "Inter", "Segoe UI", system-ui, -apple-system, "Helvetica Neue",
          "Noto Sans", "Noto Sans SC", "Noto Sans Thai", "Noto Sans Vietnamese",
          "Microsoft YaHei", sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--txt);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Ambient background: grid + glows */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(900px 480px at 85% -10%, rgba(14, 165, 233, 0.16), transparent 60%),
    radial-gradient(760px 420px at -10% 30%, rgba(45, 212, 191, 0.10), transparent 60%),
    radial-gradient(800px 500px at 50% 110%, rgba(34, 211, 238, 0.08), transparent 60%),
    var(--bg);
}
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(148, 168, 190, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 168, 190, 0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 30%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 30%, transparent 100%);
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.wrap { width: min(1180px, 92vw); margin: 0 auto; }

/* ---------------- Navigation ---------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(7, 13, 24, 0.78);
  border-bottom: 1px solid var(--line);
}
.nav .wrap {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 28px;
}
.logo {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.14em;
  color: var(--txt);
  display: inline-flex;
  align-items: baseline;
  gap: 1px;
  white-space: nowrap;
}
.logo .x {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 900;
  text-shadow: 0 0 18px rgba(34, 211, 238, 0.45);
}
.logo-img {
  height: 38px;
  width: auto;
  display: block;
  filter: drop-shadow(0 0 14px rgba(34, 211, 238, 0.35)) drop-shadow(0 2px 10px rgba(0, 0, 0, 0.55));
  transition: filter .25s;
}
a.logo:hover .logo-img {
  filter: drop-shadow(0 0 20px rgba(34, 211, 238, 0.55)) drop-shadow(0 2px 10px rgba(0, 0, 0, 0.55));
}
footer .logo-img { height: 30px; }
.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  padding: 8px 14px;
  border-radius: 10px;
  font-size: 14.5px;
  font-weight: 500;
  color: var(--mut);
  transition: color .2s, background .2s;
  white-space: nowrap;
}
.nav-links a:hover { color: var(--txt); background: rgba(34, 211, 238, 0.08); }
.nav-links a.active { color: var(--cy); background: rgba(34, 211, 238, 0.10); }
.nav-cta {
  padding: 9px 18px !important;
  border-radius: 10px !important;
  background: var(--grad);
  color: #04121c !important;
  font-weight: 700 !important;
  box-shadow: var(--glow);
}
.nav-cta:hover { filter: brightness(1.1); background: var(--grad) !important; }

/* Language switcher */
.lang { position: relative; margin-left: 6px; }
.lang-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 13px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(18, 35, 58, 0.6);
  color: var(--txt);
  font-family: var(--font);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color .2s;
}
.lang-btn:hover { border-color: var(--line-strong); }
.lang-btn .caret { font-size: 9px; color: var(--cy); }
.lang-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 8px);
  min-width: 168px;
  background: var(--panel-solid);
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 6px;
  display: none;
  z-index: 120;
}
.lang.open .lang-menu { display: block; }
.lang-menu button {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 9px 12px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--mut);
  font-family: var(--font);
  font-size: 13.5px;
  cursor: pointer;
  text-align: left;
}
.lang-menu button:hover { background: rgba(34, 211, 238, 0.08); color: var(--txt); }
.lang-menu button.sel { color: var(--cy); font-weight: 700; }
.lang-menu button .code { font-size: 11px; color: var(--mut-2); letter-spacing: .08em; }

/* Hamburger */
.burger {
  display: none;
  margin-left: auto;
  width: 42px;
  height: 42px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  position: relative;
}
.burger span, .burger span::before, .burger span::after {
  content: "";
  position: absolute;
  left: 11px;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: var(--cy);
  transition: transform .25s, opacity .2s, top .25s;
}
.burger span { top: 20px; }
.burger span::before { left: 0; top: -6px; }
.burger span::after { left: 0; top: 6px; }
.nav.open .burger span { background: transparent; }
.nav.open .burger span::before { top: 0; transform: rotate(45deg); }
.nav.open .burger span::after { top: 0; transform: rotate(-45deg); }

/* ---------------- Typography & sections ---------------- */
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cy);
}
.kicker::before {
  content: "";
  width: 26px;
  height: 2px;
  background: var(--grad);
  border-radius: 2px;
  box-shadow: var(--glow);
}
h1, h2, h3 { line-height: 1.18; font-weight: 800; letter-spacing: -0.01em; }
h1 { font-size: clamp(34px, 5vw, 58px); }
h2 { font-size: clamp(26px, 3.4vw, 40px); }
h3 { font-size: 19px; font-weight: 700; }
.grad-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.lead { color: var(--mut); font-size: clamp(15px, 1.4vw, 17.5px); max-width: 68ch; }

section { padding: 88px 0; }
.sec-head { margin-bottom: 44px; display: flex; flex-direction: column; gap: 14px; }
.sec-head .lead { margin-top: 2px; }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 28px;
  border-radius: 12px;
  border: 1px solid transparent;
  font-family: var(--font);
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  transition: transform .2s, box-shadow .2s, border-color .2s, background .2s;
}
.btn-primary { background: var(--grad); color: #04121c; box-shadow: var(--glow); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 0 34px rgba(34, 211, 238, 0.4); }
.btn-ghost { border-color: var(--line-strong); color: var(--cy); background: rgba(34, 211, 238, 0.06); }
.btn-ghost:hover { background: rgba(34, 211, 238, 0.12); transform: translateY(-2px); }
.btn-sm { padding: 9px 18px; font-size: 13.5px; border-radius: 10px; }

/* ---------------- Cards / grids ---------------- */
.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: transform .25s, border-color .25s, box-shadow .25s;
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: var(--grad);
  opacity: 0;
  transition: opacity .25s;
}
.card:hover { transform: translateY(-5px); border-color: var(--line-strong); box-shadow: var(--shadow); }
.card:hover::before { opacity: 1; }

.icon-box {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--grad-soft);
  border: 1px solid var(--line);
  margin-bottom: 18px;
  color: var(--cy);
}
.icon-box svg { width: 24px; height: 24px; }

.card h3 { margin-bottom: 10px; }
.card p { color: var(--mut); font-size: 14.5px; }

.feat { margin-top: 14px; display: flex; flex-direction: column; gap: 9px; }
.feat li {
  position: relative;
  padding-left: 22px;
  color: var(--mut);
  font-size: 14px;
  line-height: 1.5;
}
.feat li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 8px;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--grad);
  box-shadow: 0 0 8px rgba(34, 211, 238, 0.55);
  transform: rotate(45deg);
}

.tag {
  display: inline-block;
  padding: 4px 11px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(34, 211, 238, 0.07);
  color: var(--cy);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

/* ---------------- Hero ---------------- */
.hero { padding: 96px 0 72px; position: relative; }
.hero .wrap { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.hero h1 { margin: 18px 0 20px; }
.hero .lead { margin-bottom: 32px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-visual { position: relative; }
.hero-visual img {
  border-radius: 22px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow), 0 0 60px rgba(34, 211, 238, 0.12);
}
.hero-visual::after {
  content: "";
  position: absolute;
  inset: -18px;
  border-radius: 30px;
  border: 1px dashed rgba(34, 211, 238, 0.22);
  pointer-events: none;
}

/* Page hero (sub pages) */
.page-hero { padding: 84px 0 40px; }
.page-hero h1 { margin: 16px 0 18px; max-width: 22ch; }
.page-hero .visual { margin-top: 40px; }
.page-hero .visual img {
  border-radius: 22px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

/* ---------------- Stats ---------------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
  padding: 34px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.stat .v {
  font-size: clamp(30px, 3.6vw, 44px);
  font-weight: 900;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.02em;
}
.stat .l { color: var(--mut); font-size: 13.5px; margin-top: 4px; }

/* ---------------- Flow steps ---------------- */
.flow { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: step; }
.flow-3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 900px) { .flow-3 { grid-template-columns: 1fr; } }
.step { position: relative; padding: 26px 24px 24px; }
.step .num {
  position: absolute;
  top: -16px;
  left: 24px;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--grad);
  color: #04121c;
  font-weight: 900;
  font-size: 15px;
  box-shadow: var(--glow);
}
.step h3 { margin: 8px 0 8px; }
.step p { color: var(--mut); font-size: 14px; }

/* ---------------- Diagram (SVG) ---------------- */
.diagram-box {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px;
  overflow-x: auto;
}
.diagram-box svg { width: 100%; min-width: 760px; height: auto; display: block; }
.dg-node { fill: #12233a; stroke: rgba(34, 211, 238, 0.45); stroke-width: 1.4; }
.dg-node-cloud { fill: rgba(34, 211, 238, 0.14); stroke: #22d3ee; stroke-width: 1.8; }
.dg-node-boh { fill: #12233a; stroke: rgba(45, 212, 191, 0.5); stroke-width: 1.4; }
.dg-label { fill: #e8f1fa; font-size: 14px; font-weight: 700; font-family: var(--font); }
.dg-label-sm { fill: #94a8be; font-size: 12px; font-family: var(--font); }
.dg-line { stroke: rgba(34, 211, 238, 0.5); stroke-width: 1.6; stroke-dasharray: 6 6; fill: none; }
.dg-line-solid { stroke: rgba(45, 212, 191, 0.55); stroke-width: 1.6; fill: none; }

/* ---------------- Logo wall ---------------- */
.logo-wall { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; margin-top: 34px; }
.logo-ph {
  height: 74px;
  border-radius: 12px;
  border: 1px dashed rgba(148, 168, 190, 0.28);
  background: rgba(148, 168, 190, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--mut-2);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.24em;
}
.wall-note { color: var(--mut-2); font-size: 13px; margin-top: 14px; }

/* ---------------- Chips ---------------- */
.chips { display: flex; flex-wrap: wrap; gap: 12px; }
.chip {
  padding: 10px 18px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(18, 35, 58, 0.55);
  color: var(--mut);
  font-size: 13.5px;
  font-weight: 600;
}
.chip b { color: var(--cy); font-weight: 700; }

/* ---------------- CTA band ---------------- */
.cta-band {
  position: relative;
  border-radius: 24px;
  border: 1px solid var(--line-strong);
  background:
    radial-gradient(600px 240px at 20% 0%, rgba(34, 211, 238, 0.16), transparent 60%),
    radial-gradient(600px 240px at 90% 100%, rgba(45, 212, 191, 0.12), transparent 60%),
    var(--panel-solid);
  padding: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
  overflow: hidden;
}
.cta-band h2 { max-width: 26ch; }
.cta-band p { color: var(--mut); margin-top: 10px; max-width: 52ch; }

/* ---------------- Forms ---------------- */
.form-card { max-width: 760px; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { display: flex; flex-direction: column; gap: 8px; }
.field.full { grid-column: 1 / -1; }
.field label { font-size: 13px; font-weight: 700; color: var(--mut); letter-spacing: 0.04em; }
.field input, .field select, .field textarea {
  background: rgba(7, 13, 24, 0.65);
  border: 1px solid var(--line);
  border-radius: 11px;
  padding: 13px 15px;
  color: var(--txt);
  font-family: var(--font);
  font-size: 14.5px;
  outline: none;
  transition: border-color .2s, box-shadow .2s;
}
.field textarea { min-height: 120px; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus {
  border-color: var(--line-strong);
  box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.12);
}
.field select option { background: var(--panel-solid); }
.checks { display: flex; flex-wrap: wrap; gap: 10px; }
.checks label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 15px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(18, 35, 58, 0.55);
  color: var(--mut);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color .2s, color .2s;
}
.checks label:hover { border-color: var(--line-strong); }
.checks input { accent-color: var(--cy); width: 15px; height: 15px; }
.checks input:checked + span { color: var(--cy); }
.form-note { color: var(--mut-2); font-size: 12.5px; margin-top: 16px; }
.form-success {
  display: none;
  margin-top: 20px;
  padding: 16px 20px;
  border-radius: 12px;
  border: 1px solid rgba(45, 212, 191, 0.45);
  background: rgba(45, 212, 191, 0.10);
  color: var(--teal);
  font-weight: 600;
  font-size: 14.5px;
}
.form-success.show { display: block; }

/* ---------------- FAQ ---------------- */
.faq { display: flex; flex-direction: column; gap: 14px; max-width: 860px; }
.faq details {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px 24px;
  transition: border-color .2s;
}
.faq details[open] { border-color: var(--line-strong); }
.faq summary {
  cursor: pointer;
  font-weight: 700;
  font-size: 15.5px;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--cy); font-size: 20px; font-weight: 400; transition: transform .2s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { color: var(--mut); font-size: 14.5px; margin-top: 12px; }

/* ---------------- Footer ---------------- */
footer { border-top: 1px solid var(--line); margin-top: 40px; background: rgba(7, 13, 24, 0.6); }
.foot-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 36px;
  padding: 56px 0 40px;
}
.foot-grid p { color: var(--mut); font-size: 14px; margin-top: 14px; max-width: 34ch; }
.foot-grid h4 {
  font-size: 12.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mut-2);
  margin-bottom: 16px;
}
.foot-grid ul { display: flex; flex-direction: column; gap: 10px; }
.foot-grid ul a { color: var(--mut); font-size: 14px; transition: color .2s; }
.foot-grid ul a:hover { color: var(--cy); }
.foot-x { color: var(--cy); font-size: 13.5px; font-weight: 600; margin-top: 18px; }
.foot-bar {
  border-top: 1px solid var(--line);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  color: var(--mut-2);
  font-size: 13px;
}

/* ---------------- Extras ---------------- */
.card.wide .feat { display: grid; grid-template-columns: 1fr 1fr; gap: 9px 26px; }
.contact-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: 22px; align-items: start; }
.prose { max-width: 900px; display: flex; flex-direction: column; gap: 16px; }
.prose p { color: var(--mut); font-size: 15.5px; }
.mut-small { color: var(--mut); font-size: 13.5px; font-weight: 600; letter-spacing: 0.04em; }
.direct-mail { color: var(--cy); font-weight: 700; font-size: 17px; display: inline-block; margin: 6px 0 16px; }
.direct-mail:hover { text-shadow: 0 0 14px rgba(34, 211, 238, 0.5); }
.direct-wa { display: inline-flex; align-items: center; gap: 8px; }
.direct-wa:hover { text-shadow: 0 0 14px rgba(34, 211, 238, 0.5); }
.wa-ico { width: 20px; height: 20px; flex: none; color: #25D366; }
@media (max-width: 900px) {
  .contact-grid { grid-template-columns: 1fr; }
  .card.wide .feat { grid-template-columns: 1fr; }
}

/* ---------------- Reveal animation ---------------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------------- Responsive ---------------- */
@media (max-width: 1020px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .flow { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .logo-wall { grid-template-columns: repeat(3, 1fr); }
  .hero .wrap { grid-template-columns: 1fr; gap: 40px; }
  .foot-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .burger { display: block; }
  .logo-img { height: 28px; }
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
    padding: 18px 4vw 26px;
    background: rgba(7, 13, 24, 0.97);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(16px);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: opacity .25s, transform .25s;
  }
  .nav.open .nav-links { transform: none; opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 13px 16px; font-size: 15.5px; }
  .lang { margin-left: 0; margin-right: 8px; order: 2; }
  .nav .wrap { gap: 12px; }
}
@media (max-width: 620px) {
  section { padding: 64px 0; }
  .grid-2, .grid-3, .grid-4, .flow { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; gap: 18px; }
  .logo-wall { grid-template-columns: repeat(2, 1fr); }
  .form-grid { grid-template-columns: 1fr; }
  .cta-band { padding: 36px 26px; }
  .foot-grid { grid-template-columns: 1fr; gap: 28px; }
}