:root {
  --blue: #0b4f8a;
  --blue-dark: #073a66;
  --orange: #e8772e;
  --ink: #1d2733;
  --muted: #5b6b7b;
  --bg: #ffffff;
  --soft: #f4f7fa;
  --line: #e2e8ee;
  --radius: 10px;
  --maxw: 1140px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue",
    "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
}
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
.visually-hidden { position: absolute; left: -9999px; }
h1, h2, h3 { line-height: 1.25; color: var(--blue-dark); }

/* Header */
.site-header {
  background: var(--bg);
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 50;
}
.header-inner { display: flex; align-items: center; gap: 18px; height: 68px; }
.brand { display: flex; flex-direction: column; line-height: 1.1; }
.brand-name { font-weight: 800; font-size: 20px; color: var(--blue); }
.brand-sub { font-size: 11px; color: var(--muted); }
.main-nav { display: flex; gap: 18px; margin-left: auto; }
.main-nav a { color: var(--ink); font-weight: 600; font-size: 15px; }
.main-nav a.active, .main-nav a:hover { color: var(--orange); }
.header-tools { display: flex; align-items: center; gap: 10px; }
.lang-switch select {
  border: 1px solid var(--line); border-radius: 8px; padding: 6px 8px;
  background: var(--soft); font-size: 13px; cursor: pointer;
}
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  border-radius: 8px; padding: 8px 14px; font-weight: 700; font-size: 14px;
  border: 1px solid transparent; cursor: pointer;
}
.btn-whatsapp { background: #25d366; color: #fff; }
.btn-whatsapp:hover { background: #1ebe5b; text-decoration: none; }
.btn-chat { background: var(--blue); color: #fff; }
.btn-chat:hover { background: var(--blue-dark); }
.btn-primary { background: var(--orange); color: #fff; }
.btn-primary:hover { background: #d3681f; text-decoration: none; }
.btn-outline { border-color: var(--blue); color: var(--blue); background: #fff; }
.btn-outline:hover { background: var(--soft); }
.link-btn { background: none; border: none; color: var(--orange); cursor: pointer; font: inherit; padding: 0; }
.link-btn:hover { text-decoration: underline; }

/* Hero */
.hero { background: linear-gradient(135deg, var(--blue-dark), var(--blue)); color: #fff; padding: 70px 0; }
.hero h1 { color: #fff; font-size: 40px; margin: 0 0 14px; }
.hero .lead { font-size: 19px; max-width: 720px; opacity: 0.95; }
.hero-cta { margin-top: 26px; display: flex; gap: 14px; flex-wrap: wrap; }
.hero .btn-outline { color: #fff; border-color: rgba(255,255,255,.6); }

/* Sections */
.features { padding: 56px 20px; }
.features h2, .why h2 { text-align: center; font-size: 28px; margin-bottom: 28px; }
.card-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: #fff; transition: box-shadow .2s, transform .2s; }
.card:hover { box-shadow: 0 8px 24px rgba(11,79,138,.12); transform: translateY(-3px); }
.card-img { height: 150px; background: var(--soft) center/cover no-repeat; }
.card h3 { margin: 14px 16px 6px; font-size: 17px; }
.card p { margin: 0 16px 14px; color: var(--muted); font-size: 14px; }
.card-link { display: block; margin: 0 16px 16px; font-weight: 700; font-size: 14px; }

.why { padding: 10px 20px 60px; }
.why-list { list-style: none; padding: 0; max-width: 820px; margin: 0 auto; }
.why-list li { padding: 12px 0 12px 28px; border-bottom: 1px solid var(--line); position: relative; }
.why-list li::before { content: "✓"; color: var(--orange); font-weight: 800; position: absolute; left: 0; }
.cta-line { text-align: center; margin-top: 26px; font-size: 17px; }

/* Generic page */
.page { padding: 48px 20px 64px; max-width: 880px; }
.page h1 { font-size: 32px; margin-bottom: 18px; }

/* Products page */
.product-block { display: grid; grid-template-columns: 220px 1fr; gap: 24px; padding: 26px 0; border-bottom: 1px solid var(--line); scroll-margin-top: 90px; }
.product-block .pb-img { height: 160px; background: var(--soft) center/cover no-repeat; border-radius: var(--radius); }
.product-block h2 { margin: 0 0 8px; font-size: 22px; }
.product-block .specs { list-style: none; padding: 0; margin: 10px 0 0; }
.product-block .specs li { padding: 4px 0; color: var(--muted); font-size: 14px; }
.product-block .pb-cta { margin-top: 14px; }

/* Contact / RFQ */
.rfq { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; margin-top: 10px; }
.rfq form { display: grid; gap: 12px; }
.rfq label { font-weight: 600; font-size: 14px; }
.rfq input, .rfq textarea, .rfq select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; font: inherit;
}
.rfq textarea { min-height: 110px; resize: vertical; }
.rfq .form-msg { font-size: 14px; padding: 10px 12px; border-radius: 8px; }
.rfq .form-msg.ok { background: #e7f6ec; color: #1c7a3e; }
.rfq .form-msg.err { background: #fdeaea; color: #b3261e; }
.contact-info p { margin: 6px 0; }

/* Footer */
.site-footer { background: var(--blue-dark); color: #cfe0ef; margin-top: 40px; padding: 44px 0 18px; }
.site-footer h3 { color: #fff; font-size: 16px; margin: 0 0 12px; }
.footer-inner { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 28px; }
.site-footer a { color: #cfe0ef; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { padding: 3px 0; }
.copyright { border-top: 1px solid rgba(255,255,255,.15); margin-top: 26px; padding-top: 14px; font-size: 13px; color: #9fb6c9; }

/* Floating WhatsApp + chat */
.wa-float {
  position: fixed; right: 18px; bottom: 18px; z-index: 60;
  width: 54px; height: 54px; border-radius: 50%; background: #25d366; color: #fff;
  display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 13px;
  box-shadow: 0 6px 18px rgba(0,0,0,.25);
}
.chat-panel {
  position: fixed; right: 18px; bottom: 82px; z-index: 70; width: 340px; max-width: calc(100vw - 36px);
  background: #fff; border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 12px 40px rgba(0,0,0,.22);
  display: flex; flex-direction: column; overflow: hidden;
}
.chat-head { background: var(--blue); color: #fff; padding: 12px 14px; display: flex; justify-content: space-between; align-items: center; font-weight: 700; }
.chat-close { background: none; border: none; color: #fff; font-size: 22px; line-height: 1; cursor: pointer; }
.chat-log { height: 280px; overflow-y: auto; padding: 12px; display: flex; flex-direction: column; gap: 8px; background: var(--soft); }
.chat-msg { max-width: 85%; padding: 8px 11px; border-radius: 10px; font-size: 14px; }
.chat-msg.bot { background: #fff; border: 1px solid var(--line); align-self: flex-start; }
.chat-msg.user { background: var(--blue); color: #fff; align-self: flex-end; }
.chat-form { display: flex; gap: 8px; padding: 10px; border-top: 1px solid var(--line); }
.chat-form input { flex: 1; padding: 9px 11px; border: 1px solid var(--line); border-radius: 8px; font: inherit; }
.chat-form button { background: var(--blue); color: #fff; border: none; border-radius: 8px; padding: 0 16px; font-weight: 700; cursor: pointer; }

/* Responsive */
@media (max-width: 860px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr; }
  .rfq { grid-template-columns: 1fr; }
  .product-block { grid-template-columns: 1fr; }
  .main-nav { display: none; }
  .hero h1 { font-size: 30px; }
}
@media (max-width: 520px) {
  .card-grid { grid-template-columns: 1fr; }
}