/* ============================================================
   Lanheng Power — corporate site styles
   ============================================================ */
:root {
  --navy: #08182b;
  --navy-2: #0d2440;
  --blue: #1f6bff;
  --blue-dark: #1554d0;
  --green: #17c08a;
  --ink: #0f1b2d;
  --muted: #5a6b82;
  --line: #e4eaf3;
  --bg: #f5f8fc;
  --white: #ffffff;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 18px 40px -22px rgba(9, 30, 66, .25);
  --shadow-sm: 0 6px 18px -10px rgba(9, 30, 66, .25);
  --max: 1200px;
  --header-h: 76px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; }

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

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 26px;
  border-radius: 999px;
  font-weight: 650;
  font-size: 15px;
  letter-spacing: .2px;
  border: 1px solid transparent;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 14px 26px -14px rgba(31, 107, 255, .8);
}
.btn-primary:hover { background: var(--blue-dark); }
.btn-ghost {
  border-color: rgba(255, 255, 255, .35);
  color: #fff;
  background: rgba(255, 255, 255, .06);
  backdrop-filter: blur(6px);
}
.btn-ghost:hover { background: rgba(255, 255, 255, .14); }
.btn-dark { background: var(--navy); color: #fff; }
.btn-dark:hover { background: var(--navy-2); }
.btn-sm { padding: 10px 18px; font-size: 14px; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 40px; height: 40px; border-radius: 12px;
  background: linear-gradient(135deg, var(--blue), #4f9bff 55%, var(--green));
  display: grid; place-items: center;
  box-shadow: 0 10px 20px -12px rgba(31, 107, 255, .9);
}
.brand-mark svg { width: 22px; height: 22px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text b { font-size: 18px; letter-spacing: .4px; }
.brand-text span { font-size: 11px; color: var(--muted); letter-spacing: 2.4px; text-transform: uppercase; }

.main-nav { display: flex; align-items: center; gap: 6px; }
.nav-link {
  padding: 10px 14px;
  border-radius: 10px;
  font-size: 15px;
  color: #2b3a50;
  font-weight: 550;
}
.nav-link:hover { background: var(--bg); color: var(--blue); }
.nav-link.active { color: var(--blue); }

.header-right { display: flex; align-items: center; gap: 12px; }

/* language */
.lang { position: relative; }
.lang-btn {
  display: flex; align-items: center; gap: 7px;
  background: transparent; border: 1px solid var(--line);
  padding: 9px 12px; border-radius: 999px; color: #2b3a50;
  font-size: 14px;
}
.lang-btn:hover { border-color: #c9d6e8; }
.lang-btn svg { width: 16px; height: 16px; opacity: .75; }
.lang-menu {
  position: absolute; right: 0; top: calc(100% + 8px);
  background: #fff; border: 1px solid var(--line);
  border-radius: 12px; box-shadow: var(--shadow);
  padding: 6px; min-width: 150px; display: none;
}
.lang.open .lang-menu { display: block; }
.lang-menu button {
  display: flex; width: 100%; align-items: center; gap: 10px;
  padding: 9px 12px; border: 0; background: transparent;
  border-radius: 8px; font-size: 14px; color: #2b3a50; text-align: left;
}
.lang-menu button:hover { background: var(--bg); }
.lang-menu button.active { color: var(--blue); font-weight: 650; }

.menu-toggle {
  display: none; border: 1px solid var(--line); background: #fff;
  width: 42px; height: 42px; border-radius: 12px;
}
.menu-toggle span { display: block; width: 18px; height: 2px; background: var(--ink); margin: 4px auto; }

/* ---------- hero ---------- */
.hero {
  position: relative;
  min-height: 640px;
  display: flex;
  align-items: center;
  color: #fff;
  background: var(--navy);
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background-image: url("../img/pv-carport.jpg");
  background-size: cover;
  background-position: center 60%;
  transform: scale(1.03);
  filter: saturate(.9);
}
.hero::after {
  content: "";
  position: absolute; inset: 0;
  background:
    linear-gradient(100deg, rgba(6, 18, 34, .96) 0%, rgba(6, 18, 34, .82) 45%, rgba(6, 18, 34, .35) 100%),
    linear-gradient(180deg, rgba(6, 18, 34, .55), rgba(6, 18, 34, .2));
}
.hero .container { position: relative; z-index: 2; padding-top: 90px; padding-bottom: 90px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  border: 1px solid rgba(255, 255, 255, .22);
  background: rgba(255, 255, 255, .08);
  padding: 7px 14px; border-radius: 999px;
  font-size: 13px; letter-spacing: .6px; color: #cfe0f7;
}
.hero-badge i { width: 7px; height: 7px; border-radius: 50%; background: var(--green); display: inline-block; }
.hero h1 {
  font-size: clamp(36px, 5.2vw, 62px);
  line-height: 1.08;
  margin: 22px 0 18px;
  letter-spacing: -1.2px;
  max-width: 760px;
  font-weight: 750;
}
.hero h1 em { font-style: normal; color: #7fe3c0; }
.hero p.lead {
  font-size: clamp(16px, 1.6vw, 19px);
  color: #c3d3e8;
  max-width: 620px;
  margin: 0 0 32px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* stats strip */
.stats {
  position: relative; z-index: 3;
  margin-top: -46px;
}
.stats-inner {
  display: grid; grid-template-columns: repeat(4, 1fr);
  background: #fff; border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden;
  border: 1px solid var(--line);
}
.stat { padding: 26px 28px; border-right: 1px solid var(--line); }
.stat:last-child { border-right: 0; }
.stat b { display: block; font-size: 30px; letter-spacing: -.5px; color: var(--navy); }
.stat b span { color: var(--blue); }
.stat small { color: var(--muted); font-size: 13.5px; letter-spacing: .2px; }

/* ---------- sections ---------- */
.section { padding: 92px 0; }
.section.tight { padding: 64px 0; }
.section.alt { background: var(--bg); }
.section-head { max-width: 700px; margin-bottom: 48px; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 12.5px; font-weight: 700; letter-spacing: 2.2px;
  text-transform: uppercase; color: var(--blue); margin-bottom: 14px;
}
.eyebrow::before { content: ""; width: 22px; height: 2px; background: var(--green); border-radius: 2px; }
.section h2 {
  font-size: clamp(28px, 3.2vw, 40px);
  line-height: 1.18; margin: 0 0 14px; letter-spacing: -.6px;
}
.section-head p { color: var(--muted); font-size: 16.5px; margin: 0; }

/* ---------- product cards ---------- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 24px;
}
.product-card { grid-column: span 3; }
.product-card:nth-child(n+3) { grid-column: span 2; }
.product-card {
  background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
  display: flex; flex-direction: column;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: #d3e0f2; }
.product-media { position: relative; aspect-ratio: 4 / 3; overflow: hidden; background: #eef3f9; }
.product-media img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s ease; }
.product-card:hover .product-media img { transform: scale(1.05); }
.product-num {
  position: absolute; left: 14px; top: 14px;
  background: rgba(8, 24, 43, .78); color: #fff;
  font-size: 12px; letter-spacing: 1.5px; padding: 6px 10px; border-radius: 999px;
  backdrop-filter: blur(4px);
}
.product-body { padding: 24px 24px 26px; display: flex; flex-direction: column; gap: 10px; flex: 1; }
.product-body h3 { margin: 0; font-size: 20px; letter-spacing: -.2px; }
.product-body p { margin: 0; color: var(--muted); font-size: 14.8px; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: auto; padding-top: 8px; }
.tag {
  font-size: 12px; color: #23508f; background: #eaf1fd;
  border-radius: 999px; padding: 5px 10px; letter-spacing: .2px;
}
.product-link { margin-top: 14px; font-weight: 650; color: var(--blue); font-size: 14.5px; }
.product-link::after { content: " →"; }

/* ---------- features ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.feature {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 26px 24px;
}
.feature .ico {
  width: 44px; height: 44px; border-radius: 12px;
  background: #eef4ff; color: var(--blue);
  display: grid; place-items: center; margin-bottom: 16px;
}
.feature .ico svg { width: 22px; height: 22px; }
.feature h3 { margin: 0 0 8px; font-size: 16.5px; }
.feature p { margin: 0; color: var(--muted); font-size: 14.2px; }

/* ---------- split ---------- */
.split { display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }
.split-media { position: relative; }
.split-media img { border-radius: var(--radius); box-shadow: var(--shadow); }
.split-media::before {
  content: ""; position: absolute; inset: -18px -18px auto auto;
  width: 140px; height: 140px; border-radius: 24px;
  background: linear-gradient(135deg, rgba(31, 107, 255, .16), rgba(23, 192, 138, .16));
  z-index: -1;
}
.split h2 { font-size: clamp(26px, 3vw, 36px); margin: 0 0 16px; letter-spacing: -.5px; }
.split p { color: var(--muted); margin: 0 0 16px; }
.check-list { list-style: none; padding: 0; margin: 22px 0 30px; display: grid; gap: 12px; }
.check-list li { display: flex; gap: 10px; align-items: flex-start; font-size: 15px; }
.check-list svg { flex: 0 0 20px; width: 20px; height: 20px; color: var(--green); margin-top: 3px; }

/* ---------- markets ---------- */
.market-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 14px; }
.market {
  background: #fff; border: 1px solid var(--line); border-radius: 12px;
  padding: 16px 14px; text-align: center; font-size: 14.5px; color: #2b3a50;
  transition: .2s;
}
.market:hover { border-color: #bcd2f5; color: var(--blue); transform: translateY(-3px); }
.market b { display: block; font-size: 11px; letter-spacing: 1.2px; color: var(--muted); text-transform: uppercase; margin-bottom: 4px; font-weight: 600; }

/* ---------- CTA band ---------- */
.cta-band {
  position: relative; overflow: hidden;
  background: linear-gradient(120deg, var(--navy) 0%, #12325c 55%, #1b4d8f 100%);
  color: #fff; border-radius: 24px;
  padding: 54px 56px;
  display: flex; align-items: center; justify-content: space-between; gap: 30px;
}
.cta-band::before {
  content: ""; position: absolute; right: -60px; top: -60px;
  width: 320px; height: 320px; border-radius: 50%;
  background: radial-gradient(circle, rgba(23, 192, 138, .35), transparent 65%);
}
.cta-band h2 { margin: 0 0 8px; font-size: clamp(24px, 2.6vw, 32px); letter-spacing: -.4px; }
.cta-band p { margin: 0; color: #bfd2ec; }
.cta-band .btn { position: relative; z-index: 2; }

/* ---------- page hero ---------- */
.page-hero {
  background: radial-gradient(1200px 400px at 15% -10%, #173a66 0%, transparent 60%), var(--navy);
  color: #fff; padding: 84px 0 72px;
}
.page-hero .eyebrow { color: #8fd8c0; }
.page-hero h1 { font-size: clamp(32px, 4vw, 48px); margin: 0 0 14px; letter-spacing: -.8px; }
.page-hero p { max-width: 720px; color: #c3d3e8; font-size: 17px; margin: 0; }

/* ---------- products page ---------- */
.product-block {
  display: grid; grid-template-columns: 1fr 1fr; gap: 50px;
  align-items: center; padding: 70px 0;
  border-bottom: 1px solid var(--line);
}
.product-block:last-child { border-bottom: 0; }
.product-block.rev .pb-media { order: 2; }
.pb-media img { border-radius: var(--radius); box-shadow: var(--shadow); width: 100%; }
.pb-media { position: relative; }
.pb-num {
  position: absolute; left: -10px; top: -14px;
  background: var(--blue); color: #fff; font-weight: 700;
  width: 46px; height: 46px; border-radius: 14px;
  display: grid; place-items: center; box-shadow: 0 12px 22px -12px rgba(31, 107, 255, .9);
}
.pb-body h2 { font-size: clamp(24px, 2.6vw, 32px); margin: 0 0 12px; letter-spacing: -.4px; }
.pb-body > p { color: var(--muted); margin: 0 0 18px; }
.spec-table { width: 100%; border-collapse: collapse; margin: 18px 0 24px; font-size: 14.2px; }
.spec-table th, .spec-table td { padding: 10px 12px; border-bottom: 1px solid var(--line); text-align: left; }
.spec-table th { color: var(--muted); font-weight: 600; width: 38%; }
.spec-table td { color: #22324a; font-weight: 550; }
.spec-table tr:last-child th, .spec-table tr:last-child td { border-bottom: 0; }

/* ---------- about ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: start; }
.about-text p { color: var(--muted); margin: 0 0 16px; }
.about-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.about-stat {
  background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 22px;
}
.about-stat b { display: block; font-size: 26px; color: var(--navy); letter-spacing: -.5px; }
.about-stat span { color: var(--muted); font-size: 13.5px; }
.about-gallery { display: grid; grid-template-columns: 1.2fr .8fr; gap: 16px; margin-top: 20px; }
.about-gallery img { border-radius: 14px; width: 100%; height: 100%; object-fit: cover; }
.about-gallery .tall { grid-row: span 2; }

/* ---------- contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 50px; }
.contact-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 13.5px; color: #33445c; margin-bottom: 7px; font-weight: 600; }
.field input, .field select, .field textarea {
  width: 100%; border: 1px solid #d8e2f0; border-radius: 10px;
  padding: 12px 14px; font: inherit; font-size: 14.5px; color: var(--ink);
  background: #fbfdff; transition: .2s;
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--blue); box-shadow: 0 0 0 3px rgba(31, 107, 255, .12);
}
.field textarea { min-height: 120px; resize: vertical; }
.contact-info { display: grid; gap: 18px; }
.info-item { display: flex; gap: 14px; align-items: flex-start; }
.info-item .ico {
  flex: 0 0 42px; width: 42px; height: 42px; border-radius: 12px;
  background: #eef4ff; color: var(--blue); display: grid; place-items: center;
}
.info-item .ico svg { width: 20px; height: 20px; }
.info-item b { display: block; font-size: 14.5px; }
.info-item span, .info-item a { color: var(--muted); font-size: 14.2px; }
.info-item a:hover { color: var(--blue); }
.note { font-size: 12.5px; color: var(--muted); margin-top: 14px; }

/* ---------- footer ---------- */
.site-footer { background: var(--navy); color: #c3d3e8; padding: 64px 0 26px; margin-top: 0; }
.footer-grid { display: grid; grid-template-columns: 1.4fr .8fr .8fr 1.2fr; gap: 40px; }
.footer-brand .brand-text b { color: #fff; }
.footer-brand p { color: #93a8c4; font-size: 14px; margin: 16px 0 0; max-width: 320px; }
.footer-col h4 { color: #fff; font-size: 14px; letter-spacing: .6px; margin: 0 0 14px; }
.footer-col a, .footer-col span { display: block; color: #93a8c4; font-size: 14px; padding: 5px 0; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  margin-top: 48px; padding-top: 22px; border-top: 1px solid rgba(255, 255, 255, .1);
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  color: #7f93ad; font-size: 13px;
}

/* ---------- reveal ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
@media (max-width: 1024px) {
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .product-card, .product-card:nth-child(n+3) { grid-column: auto; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .market-grid { grid-template-columns: repeat(4, 1fr); }
  .split, .about-grid, .contact-grid, .product-block { grid-template-columns: 1fr; gap: 34px; }
  .product-block.rev .pb-media { order: 0; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .stats-inner { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(2) { border-right: 0; }
  .stat:nth-child(1), .stat:nth-child(2) { border-bottom: 1px solid var(--line); }
}
@media (max-width: 860px) {
  .main-nav { display: none; }
  .menu-toggle { display: block; }
  .header-right .btn { display: none; }
  .main-nav.open {
    display: flex; position: absolute; top: var(--header-h); left: 0; right: 0;
    background: #fff; flex-direction: column; align-items: stretch;
    padding: 12px 24px 20px; border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-sm);
  }
  .main-nav.open .nav-link { padding: 13px 10px; }
  .cta-band { flex-direction: column; align-items: flex-start; padding: 40px 30px; }
}
@media (max-width: 640px) {
  .hero { min-height: 560px; }
  .hero .container { padding-top: 64px; padding-bottom: 80px; }
  .product-grid, .feature-grid, .market-grid { grid-template-columns: 1fr; }
  .market-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-inner { grid-template-columns: 1fr; }
  .stat { border-right: 0; border-bottom: 1px solid var(--line); }
  .stat:last-child { border-bottom: 0; }
  .section { padding: 64px 0; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .form-row { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: 1fr; }
  .about-gallery { grid-template-columns: 1fr; }
}

/* misc additions */
.stat b small { font-size: 15px; color: var(--muted); font-weight: 600; letter-spacing: 0; }
.form-ok {
  display: none;
  background: #e9f9f2;
  border: 1px solid #bfe9d8;
  color: #106b4c;
  padding: 13px 16px;
  border-radius: 10px;
  margin-bottom: 18px;
  font-size: 14px;
}
.about-gallery img.tall { height: 100%; }

/* product detail / certificates / cases */
.cert-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.cert-card { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 24px; }
.cert-ico { width: 42px; height: 42px; border-radius: 12px; background: #eef4ff; color: var(--blue);
  display: grid; place-items: center; font-weight: 700; font-size: 14px; margin-bottom: 14px; }
.cert-card h3 { margin: 0 0 8px; font-size: 16px; }
.cert-card p { margin: 0; color: var(--muted); font-size: 14px; }
.case-list { display: grid; gap: 12px; }
.case-item { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.case-item b { font-size: 15px; }
.app-title { margin: 0 0 14px; font-size: 18px; }
.case-label { font-size: 11.5px; letter-spacing: 1.6px; text-transform: uppercase; color: var(--blue);
  font-weight: 700; margin: 16px 0 2px; }
.product-block .pb-body > p { margin: 0 0 4px; }
@media (max-width: 1024px) { .cert-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .cert-grid { grid-template-columns: 1fr; } }