html { background: #020307; }
:root {
  --bg: #05070b;
  --panel: rgba(12, 16, 24, 0.88);
  --panel-strong: #0d1420;
  --text: #f3f7fb;
  --muted: #9aa7b6;
  --line: rgba(159, 219, 255, 0.16);
  --accent: #1df0ff;
  --accent-2: #8a5cff;
  --warning: #ffbd4a;
  --radius: 26px;
  --shadow: 0 30px 90px rgba(0,0,0,0.72);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background-color: #020307;
  background-image:
    radial-gradient(circle at 72% 8%, rgba(29,240,255,0.14), transparent 31%),
    radial-gradient(circle at 18% 0%, rgba(81,112,255,0.15), transparent 28%),
    linear-gradient(180deg, #020307 0%, var(--bg) 45%, #020307 100%);
  background-attachment: fixed;
  min-height: 100vh;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: linear-gradient(to bottom, black, transparent 78%);
}
a { color: inherit; text-decoration: none; }
.site-shell { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.nav {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; justify-content: space-between;
  padding: 22px 0;
  background: linear-gradient(180deg, rgba(2,3,7,.88), rgba(2,3,7,.58));
  backdrop-filter: blur(18px);
}
.brand { display: flex; align-items: center; gap: 12px; font-weight: 800; letter-spacing: 0.13em; }
.brand-mark { width: 12px; height: 12px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 28px var(--accent); }
.nav-links { display: flex; align-items: center; gap: 26px; color: var(--muted); font-size: 14px; }
.nav-links a { transition: color .2s ease; }
.nav-links a:hover { color: var(--text); }
.nav-links span { display: block; font-size: 11px; opacity: .58; margin-top: 2px; }
.nav-cta { color: var(--text) !important; border: 1px solid var(--line); border-radius: 999px; padding: 10px 16px; }
.menu-btn { display: none; background: transparent; color: var(--text); border: 1px solid var(--line); border-radius: 12px; padding: 8px 11px; }
.section { padding: 82px 0; position: relative; }
.section-grid { min-height: 720px; display: grid; grid-template-columns: 1.02fr .98fr; gap: 54px; align-items: center; }
.eyebrow { color: var(--accent); text-transform: uppercase; letter-spacing: .18em; font-size: 12px; font-weight: 800; margin: 0 0 18px; }
h1, h2, h3, p { margin-top: 0; }
h1 { font-size: clamp(56px, 8vw, 112px); line-height: .92; letter-spacing: -0.07em; margin-bottom: 26px; }
h1 span { color: transparent; -webkit-text-stroke: 1px rgba(255,255,255,0.72); }
h2 { font-size: clamp(36px, 5vw, 68px); line-height: 1; letter-spacing: -0.05em; margin-bottom: 18px; }
h3 { font-size: 22px; margin-bottom: 14px; }
p { color: var(--muted); line-height: 1.8; }
.lead { font-size: 21px; color: #dce7f2; max-width: 620px; }
.hero-actions, .contact-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 34px; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 22px; border-radius: 999px; font-weight: 800; letter-spacing: .02em; transition: transform .2s ease, border-color .2s ease, background .2s ease; }
.btn:hover { transform: translateY(-2px); }
.btn.primary { background: linear-gradient(135deg, var(--accent), #5f7cff); color: #020307; }
.btn.ghost { border: 1px solid var(--line); color: var(--text); }
.hero-panel { border: 1px solid var(--line); border-radius: var(--radius); background: linear-gradient(180deg, rgba(17,27,42,.94), rgba(7,10,16,.92)); box-shadow: var(--shadow); overflow: hidden; }
.panel-top { display: flex; align-items: center; gap: 8px; padding: 18px 20px; border-bottom: 1px solid var(--line); color: var(--muted); }
.panel-top span { width: 9px; height: 9px; border-radius: 999px; background: rgba(255,255,255,.25); }
.panel-top strong { margin-left: auto; font-size: 12px; letter-spacing: .16em; }
.scan-card { position: relative; min-height: 340px; margin: 24px; border-radius: 22px; background: radial-gradient(circle at center, rgba(29,240,255,.15), transparent 44%), #070b12; border: 1px solid rgba(29,240,255,.2); overflow: hidden; }
.scan-line { position: absolute; inset: 0; background: linear-gradient(180deg, transparent 0%, rgba(29,240,255,.34) 50%, transparent 100%); height: 120px; animation: scan 4s linear infinite; }
@keyframes scan { 0% { transform: translateY(-130px); } 100% { transform: translateY(360px); } }
.chip-grid { position: absolute; inset: 48px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.chip-grid i { border: 1px solid rgba(255,255,255,.14); border-radius: 14px; background: linear-gradient(135deg, rgba(255,255,255,.08), rgba(255,255,255,.02)); }
.status-row { display: flex; justify-content: space-between; padding: 16px 24px; border-top: 1px solid var(--line); color: var(--muted); letter-spacing: .08em; font-size: 13px; }
.status-row b { color: var(--accent); }
.status-row .warn { color: var(--warning); }
.section-heading { max-width: 760px; margin-bottom: 34px; }
.feature-grid, .service-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.feature-card, .service-card, .proof-card, .contact-card, .step { border: 1px solid var(--line); border-radius: var(--radius); background: linear-gradient(180deg, rgba(16,22,33,.92), rgba(7,10,16,.88)); box-shadow: 0 24px 70px rgba(0,0,0,.55); }
.feature-card { padding: 28px; min-height: 260px; }
.card-index { color: var(--accent); font-weight: 900; letter-spacing: .14em; }
.feature-card em, .service-card span { display: block; color: var(--muted); font-size: 13px; font-style: normal; margin-top: 5px; }
.services-section { padding-top: 40px; }
.service-card { padding: 30px; position: relative; overflow: hidden; }
.service-card.featured { background: linear-gradient(180deg, rgba(29,240,255,.16), rgba(8,13,21,.94)); border-color: rgba(29,240,255,.42); }
.icon { width: 52px; height: 52px; border-radius: 16px; display: grid; place-items: center; background: rgba(29,240,255,.12); color: var(--accent); font-weight: 900; margin-bottom: 22px; }
ul { margin: 22px 0 0; padding-left: 20px; color: #cbd6e2; line-height: 1.9; }
.proof-card, .contact-card { padding: clamp(32px, 6vw, 64px); }
.metrics { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 34px; }
.metrics div { border-top: 1px solid var(--line); padding-top: 18px; }
.metrics strong { display: block; font-size: 44px; letter-spacing: -0.04em; color: var(--text); }
.metrics span { color: var(--muted); font-size: 13px; }
.timeline { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.step { padding: 26px; }
.step span { color: var(--accent); font-weight: 900; }
.contact-section { padding-bottom: 110px; }
.contact-card { background: radial-gradient(circle at 78% 20%, rgba(29,240,255,.18), transparent 28%), var(--panel-strong); }
.contact-card small { color: #798697; display: block; margin-top: 22px; }
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }
@media (max-width: 920px) {
  .nav-links { display: none; position: absolute; left: 0; right: 0; top: 74px; padding: 18px; border: 1px solid var(--line); border-radius: 20px; background: rgba(6,7,10,.96); flex-direction: column; align-items: flex-start; }
  .nav-links.open { display: flex; }
  .menu-btn { display: block; }
  .section-grid, .feature-grid, .service-grid, .metrics, .timeline { grid-template-columns: 1fr; }
  .hero { min-height: auto; padding: 90px 0 50px; }
}
@media (max-width: 560px) {
  .site-shell { width: min(100% - 24px, 1180px); }
  h1 { font-size: 58px; }
  .section { padding: 56px 0; }
  .scan-card { min-height: 260px; margin: 16px; }
  .chip-grid { inset: 32px; gap: 10px; }
}

/* Bilingual display refinement */
.zh { color: #e7edf5; }
.en { color: #9aa7b6; font-size: 0.95em; }
.section-heading h2 span,
.proof-card h2 span,
.contact-card h2 span {
  display: block;
  margin-top: 10px;
  color: transparent;
  -webkit-text-stroke: 1px rgba(255,255,255,0.52);
  font-size: 0.62em;
  letter-spacing: -0.03em;
}
.feature-card p.en,
.service-card p.en,
.step p.en {
  margin-top: -4px;
  border-left: 2px solid rgba(29,240,255,.23);
  padding-left: 12px;
}
.service-card ul li { margin-bottom: 10px; }
.service-card ul li strong { display: block; color: #e7edf5; font-weight: 800; }
.service-card ul li span { display: block; color: #91a0b2; font-size: 13px; margin-top: 2px; }
.step h3 em { display: block; margin-top: 6px; color: var(--muted); font-size: 13px; font-style: normal; }
.nav-links strong { font-size: 14px; color: #e7edf5; }
.hero .lead.en { max-width: 680px; margin-top: -8px; }
@media (max-width: 560px) {
  .section-heading h2 span,
  .proof-card h2 span,
  .contact-card h2 span { font-size: 0.72em; }
}

/* Language switch mode: only show selected language */
.i18n { display: none; }
body[data-lang="zh"] .i18n.zh { display: inline; }
body[data-lang="en"] .i18n.en { display: inline; }
p.i18n, body[data-lang="zh"] p.i18n.zh, body[data-lang="en"] p.i18n.en { display: none; }
body[data-lang="zh"] p.i18n.zh, body[data-lang="en"] p.i18n.en { display: block; }
.nav-right { display: flex; align-items: center; gap: 14px; }
.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  padding: 4px;
  border: 1px solid rgba(159, 219, 255, 0.22);
  border-radius: 999px;
  background: rgba(6, 10, 16, 0.86);
  color: var(--text);
  cursor: pointer;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.03), 0 12px 30px rgba(0,0,0,.35);
}
.lang-pill {
  min-width: 42px;
  padding: 7px 10px;
  border-radius: 999px;
  color: #8f9daf;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: .04em;
  text-align: center;
  transition: background .2s ease, color .2s ease, box-shadow .2s ease;
}
.lang-pill.active {
  background: linear-gradient(135deg, var(--accent), #5f7cff);
  color: #020307;
  box-shadow: 0 0 24px rgba(29,240,255,.22);
}
body[data-lang="en"] h1 { letter-spacing: -0.05em; }
body[data-lang="en"] .lead { max-width: 720px; }
.nav-links a { font-weight: 800; }
.service-card ul li .i18n { color: #cbd6e2; font-weight: 700; }
.metrics .i18n { color: var(--muted); font-size: 13px; }
@media (max-width: 920px) {
  .nav-right { gap: 10px; }
  .lang-toggle { order: -1; }
}
@media (max-width: 560px) {
  .brand { letter-spacing: .08em; }
  .lang-pill { min-width: 36px; padding: 6px 8px; }
}

/* V5 practical industrial-service adjustments */
body {
  background-image:
    radial-gradient(circle at 72% 8%, rgba(29,240,255,0.10), transparent 31%),
    radial-gradient(circle at 18% 0%, rgba(81,112,255,0.10), transparent 28%),
    linear-gradient(180deg, #020307 0%, #05070b 45%, #020307 100%);
}
.hero-panel .equipment-card {
  min-height: 340px;
  display: grid;
  place-items: center;
  background:
    linear-gradient(135deg, rgba(255,255,255,.035), transparent 45%),
    radial-gradient(circle at center, rgba(29,240,255,.10), transparent 46%),
    #070b12;
}
.equipment-layout {
  width: min(82%, 360px);
}
.machine-body {
  min-height: 170px;
  border: 1px solid rgba(159,219,255,.26);
  border-radius: 22px;
  background: linear-gradient(180deg, rgba(16,22,33,.95), rgba(4,7,12,.96));
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.04), 0 24px 70px rgba(0,0,0,.45);
  position: relative;
  overflow: hidden;
}
.machine-body::before {
  content: "51T";
  position: absolute;
  left: 24px;
  top: 20px;
  color: rgba(243,247,251,.82);
  font-weight: 900;
  letter-spacing: .16em;
}
.machine-body::after {
  content: "INDUSTRIAL SERVICE";
  position: absolute;
  left: 24px;
  bottom: 20px;
  color: rgba(154,167,182,.8);
  font-size: 12px;
  letter-spacing: .18em;
  font-weight: 800;
}
.machine-body i {
  position: absolute;
  right: 24px;
  width: 58px;
  height: 10px;
  border-radius: 999px;
  background: rgba(29,240,255,.22);
  box-shadow: 0 0 22px rgba(29,240,255,.15);
}
.machine-body i:nth-child(1) { top: 34px; }
.machine-body i:nth-child(2) { top: 62px; width: 86px; background: rgba(255,189,74,.24); }
.machine-body i:nth-child(3) { top: 90px; width: 42px; }
.tool-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-top: 16px;
}
.tool-row b {
  border: 1px solid rgba(159,219,255,.18);
  border-radius: 14px;
  padding: 12px 8px;
  text-align: center;
  color: #cbd6e2;
  font-size: 11px;
  letter-spacing: .12em;
  background: rgba(12,16,24,.78);
}
.four-grid {
  grid-template-columns: repeat(4, 1fr);
}
@media (max-width: 1100px) {
  .four-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 920px) {
  .four-grid { grid-template-columns: 1fr; }
}