/* =========================================================
   LIDA TECH — Global Stylesheet
   Modern, professional, responsive B2B manufacturing site
   ========================================================= */

/* ---------- Design tokens ---------- */
:root {
  --c-primary: #1c1917;        /* deep charcoal */
  --c-primary-dark: #0c0a09;
  --c-accent: #ea580c;         /* orange accent */
  --c-accent-light: #fb923c;   /* light orange */
  --c-ink: #1c1917;            /* headings */
  --c-text: #57534e;           /* body text */
  --c-muted: #a8a29e;
  --c-bg: #fafaf9;
  --c-surface: #ffffff;
  --c-line: #e7e5e4;

  --radius: 14px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 3px rgba(28, 25, 23, .08);
  --shadow-md: 0 12px 32px rgba(28, 25, 23, .10);
  --shadow-lg: 0 24px 60px rgba(28, 25, 23, .14);

  --container: 1180px;
  --font-sans: "Segoe UI", "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--c-text);
  background: var(--c-bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
}

img { max-width: 100%; display: block; }
a { color: var(--c-accent); text-decoration: none; }
ul, ol { list-style: none; }

h1, h2, h3, h4 {
  color: var(--c-ink);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -.01em;
}

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

.section { padding: 88px 0; }
.section:nth-child(even) { background: var(--c-surface); }

.section-head {
  max-width: 680px;
  margin: 0 auto 52px;
  text-align: center;
}
.section-head h2 { font-size: clamp(1.8rem, 3.5vw, 2.5rem); margin: 8px 0 14px; }
.section-sub { color: var(--c-text); font-size: 1.05rem; }

.eyebrow {
  display: inline-block;
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--c-accent);
}

.note { text-align: center; margin-top: 36px; color: var(--c-text); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: 10px;
  font-weight: 600;
  font-size: .98rem;
  cursor: pointer;
  border: 1.5px solid transparent;
  transition: transform .15s ease, background .2s ease, box-shadow .2s ease, color .2s ease;
  white-space: nowrap;
}
.btn-primary { background: var(--c-accent); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: #c2410c; transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.4); }
.btn-ghost:hover { background: rgba(255,255,255,.12); transform: translateY(-2px); }
.btn-lg { padding: 15px 32px; font-size: 1.02rem; }
.btn-block { width: 100%; }

.text-link { font-weight: 600; font-size: .92rem; }
.text-link:hover { text-decoration: underline; }

/* =========================================================
   Header / Navigation
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--c-line);
  transition: box-shadow .2s ease;
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand-logo { height: 42px; width: auto; display: block; border-radius: 6px; }
.brand-mark {
  width: 34px; height: 34px; border-radius: 8px;
  background: linear-gradient(135deg, #ea580c, #f97316);
  display: grid; place-items: center;
  color: #fff; font-weight: 800; font-size: 17px;
  flex-shrink: 0;
}
.brand-name { font-size: 1.15rem; font-weight: 800; color: var(--c-ink); line-height: 1; }
.brand-sub { display: block; font-size: .62rem; font-weight: 600; letter-spacing: .18em; text-transform: uppercase; color: var(--c-muted); margin-top: 3px; }

.main-nav { display: flex; align-items: center; gap: 28px; }
.main-nav ul { display: flex; align-items: center; gap: 26px; }
.nav-link {
  color: var(--c-text);
  font-weight: 500;
  font-size: .95rem;
  padding: 6px 0;
  position: relative;
}
.nav-link::after {
  content: ""; position: absolute; left: 0; bottom: 0;
  width: 0; height: 2px; background: var(--c-accent);
  transition: width .2s ease;
}
.nav-link:hover, .nav-link.active { color: var(--c-ink); }
.nav-link:hover::after, .nav-link.active::after { width: 100%; }

.nav-cta { padding: 10px 20px; font-size: .9rem; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none; border: 0; cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 24px; height: 2px; background: var(--c-ink);
  border-radius: 2px; transition: transform .2s ease, opacity .2s ease;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* =========================================================
   Hero
   ========================================================= */
.hero {
  background: linear-gradient(160deg, #171717 0%, #1f1a16 55%, #7c2d12 135%);
  color: #fff;
  padding: 96px 0 110px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 85% 20%, rgba(251,146,60,.22), transparent 42%),
    radial-gradient(circle at 8% 92%, rgba(234,88,12,.28), transparent 46%);
  pointer-events: none;
}

.hero-wrap {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 56px;
  align-items: center;
  position: relative;
}

.hero-logo { height: 56px; width: auto; border-radius: 8px; margin-bottom: 18px; box-shadow: 0 8px 24px rgba(0,0,0,.25); }
.hero-slogan {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--c-accent-light);
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: .04em;
  margin-bottom: 10px;
}
.hero-slogan::before {
  content: "";
  width: 30px; height: 3px;
  background: var(--c-accent-light);
  border-radius: 2px;
}
.hero .eyebrow { color: var(--c-accent-light); }
.hero h1 { color: #fff; font-size: clamp(2.2rem, 5vw, 3.5rem); margin: 16px 0 20px; }
.hero h1 .accent { color: var(--c-accent-light); }
.hero-sub { color: rgba(255,255,255,.85); font-size: 1.12rem; max-width: 540px; }

.hero-actions { display: flex; gap: 14px; margin: 32px 0 36px; flex-wrap: wrap; }

.hero-points {
  display: flex; flex-wrap: wrap; gap: 12px 28px;
  color: rgba(255,255,255,.82); font-size: .92rem;
}
.hero-points li { display: flex; align-items: center; gap: 8px; }
.hero-points li::before {
  content: ""; width: 8px; height: 8px; border-radius: 50%;
  background: var(--c-accent-light);
}

.hero-visual { position: relative; }
.hero-card {
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius-lg);
  padding: 30px;
  backdrop-filter: blur(4px);
}
.hero-card-title { font-size: .8rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: rgba(255,255,255,.7); margin-bottom: 22px; }
.hero-flow { display: flex; flex-direction: column; gap: 16px; }
.flow-step {
  display: flex; align-items: center; gap: 12px;
  background: rgba(255,255,255,.08);
  padding: 12px 16px; border-radius: 10px;
  font-weight: 600; font-size: .95rem;
}
.flow-dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--c-accent-light);
  flex-shrink: 0;
}

/* =========================================================
   Products
   ========================================================= */
.grid { display: grid; gap: 26px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.product-card {
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform .2s ease, box-shadow .2s ease;
  display: flex; flex-direction: column;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.product-card img { width: 100%; aspect-ratio: 4/3; object-fit: cover; background: var(--c-bg); }
.product-info { padding: 22px 24px 26px; display: flex; flex-direction: column; gap: 10px; flex: 1; }
.product-info h3 { font-size: 1.18rem; }
.product-info p { color: var(--c-text); font-size: .95rem; flex: 1; }

/* =========================================================
   Services
   ========================================================= */
.service-card {
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: transform .2s ease, box-shadow .2s ease;
}
.service-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.service-icon {
  width: 54px; height: 54px; border-radius: 12px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, #fff7ed, #ffedd5);
  color: var(--c-accent);
  margin-bottom: 18px;
}
.service-icon svg { width: 26px; height: 26px; }
.service-card h3 { font-size: 1.15rem; margin-bottom: 10px; }
.service-card p { font-size: .95rem; }

/* =========================================================
   Process
   ========================================================= */
.process-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 22px;
  counter-reset: step;
}
.process-step {
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 30px 22px;
  position: relative;
}
.step-num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--c-accent); color: #fff;
  font-weight: 800; font-size: .9rem;
  margin-bottom: 18px;
}
.process-step h3 { font-size: 1.05rem; margin-bottom: 8px; }
.process-step p { font-size: .9rem; }

/* =========================================================
   About / Advantages
   ========================================================= */
.advantage-card {
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-left: 4px solid var(--c-accent);
  border-radius: var(--radius);
  padding: 28px;
  transition: transform .2s ease, box-shadow .2s ease;
}
.advantage-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-sm); }
.advantage-card h3 { font-size: 1.15rem; margin-bottom: 10px; }
.advantage-card p { font-size: .95rem; }

.factory-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 44px;
}
.factory-item { text-align: center; }
.factory-item img {
  width: 100%;
  aspect-ratio: 4/3;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--c-line);
  transition: transform .2s ease, box-shadow .2s ease;
}
.factory-item:hover img { transform: translateY(-4px); box-shadow: var(--shadow-sm); }
.factory-item span {
  display: block;
  margin-top: 10px;
  font-weight: 600;
  color: var(--c-ink);
  font-size: .92rem;
}

.about-note {
  margin-top: 40px;
  background: #fffbeb;
  border: 1px solid #fde68a;
  border-radius: var(--radius);
  padding: 18px 22px;
  color: #92400e;
  font-size: .92rem;
}

/* =========================================================
   Contact / Inquiry
   ========================================================= */
.contact-wrap {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 56px;
  align-items: start;
}

.contact-intro h2 { font-size: clamp(1.7rem, 3vw, 2.3rem); margin: 8px 0 14px; }

.contact-list { margin-top: 30px; display: flex; flex-direction: column; gap: 20px; }
.contact-list li { display: flex; gap: 14px; align-items: flex-start; }
.contact-icon {
  width: 44px; height: 44px; border-radius: 10px; flex-shrink: 0;
  display: grid; place-items: center;
  background: var(--c-bg); color: var(--c-accent);
}
.contact-icon svg { width: 22px; height: 22px; }
.contact-list strong { display: block; color: var(--c-ink); font-size: .95rem; }
.contact-list span { color: var(--c-text); font-size: .93rem; }
.contact-list em, .footer-col em, .form-note { font-style: normal; color: var(--c-muted); font-size: .82rem; }

.inquiry-form {
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-md);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.form-field { margin-bottom: 18px; }
.form-field label { display: block; font-weight: 600; color: var(--c-ink); font-size: .9rem; margin-bottom: 7px; }
.form-field input, .form-field select, .form-field textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--c-line);
  border-radius: 9px;
  font-family: inherit; font-size: .95rem; color: var(--c-ink);
  background: var(--c-bg);
  transition: border-color .15s ease, box-shadow .15s ease;
}
.form-field input:focus, .form-field select:focus, .form-field textarea:focus {
  outline: none; border-color: var(--c-accent);
  background: #fff; box-shadow: 0 0 0 3px rgba(234,88,12,.14);
}
.form-field textarea { resize: vertical; }
.form-note { margin-top: 14px; text-align: center; }

/* =========================================================
   Footer
   ========================================================= */
.site-footer { background: #171717; color: #d6d3d1; }
.footer-wrap {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding: 64px 24px 48px;
}
.footer-logo { height: 46px; width: auto; display: block; border-radius: 6px; }
.footer-slogan {
  margin-top: 14px;
  color: var(--c-accent-light);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: .02em;
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.footer-slogan::before {
  content: "";
  width: 22px; height: 2px;
  background: var(--c-accent-light);
  border-radius: 2px;
}
.brand-light .brand-name { color: #fff; }
.footer-brand p { font-size: .93rem; margin-top: 16px; max-width: 320px; color: #a8a29e; }
.footer-col h4 { color: #fff; font-size: .95rem; margin-bottom: 18px; }
.footer-col ul { display: flex; flex-direction: column; gap: 11px; }
.footer-col a, .footer-col li { color: #a8a29e; font-size: .92rem; }
.footer-col a:hover { color: #fff; }

.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); }
.footer-bottom-wrap { padding: 20px 24px; }
.footer-bottom p { font-size: .85rem; color: #a8a29e; }

/* =========================================================
   Reveal animation
   ========================================================= */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .6s ease, transform .6s ease;
}
.reveal.visible { opacity: 1; transform: none; }

/* =========================================================
   Responsive — tablet
   ========================================================= */
@media (max-width: 1024px) {
  .hero-wrap { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { max-width: 520px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .process-steps { grid-template-columns: repeat(3, 1fr); }
  .contact-wrap { grid-template-columns: 1fr; gap: 40px; }
  .footer-wrap { grid-template-columns: repeat(2, 1fr); }
  .factory-strip { grid-template-columns: repeat(2, 1fr); }
}

/* =========================================================
   Responsive — mobile
   ========================================================= */
@media (max-width: 768px) {
  .section { padding: 60px 0; }

  .nav-toggle { display: flex; }
  .main-nav {
    position: absolute;
    top: 72px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--c-line);
    box-shadow: var(--shadow-md);
    padding: 12px 24px 24px;
    display: none;
  }
  .main-nav.open { display: flex; }
  .main-nav ul { flex-direction: column; align-items: stretch; gap: 4px; }
  .nav-link { display: block; padding: 12px 4px; font-size: 1rem; border-bottom: 1px solid var(--c-bg); }
  .nav-link::after { display: none; }
  .nav-cta { margin-top: 14px; }

  .hero { padding: 64px 0 80px; }
  .hero-actions .btn { flex: 1 1 100%; }

  .grid-3, .grid-2 { grid-template-columns: 1fr; }
  .process-steps { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .inquiry-form { padding: 24px; }
  .footer-wrap { grid-template-columns: 1fr; gap: 32px; padding: 48px 24px 32px; }
  .factory-strip { grid-template-columns: 1fr; }
}