:root {
  --green: #0e7a4f;
  --green-dark: #0a5c3b;
  --ink: #1d2b26;
  --muted: #5b6b64;
  --bg: #ffffff;
  --bg-alt: #f3f7f5;
  --line: #e2e9e6;
  --radius: 12px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Segoe UI", "Helvetica Neue", Arial, "PingFang SC", sans-serif;
  color: var(--ink); background: var(--bg); line-height: 1.65; font-size: 16px;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--green); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 20px; }
h1 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); line-height: 1.25; margin: 18px 0 14px; }
h2 { font-size: clamp(1.3rem, 2.5vw, 1.7rem); margin: 26px 0 14px; }
h3 { font-size: 1.1rem; margin: 14px 0 8px; }
main { padding: 30px 0 50px; }

/* header */
.site-header {
  position: sticky; top: 0; z-index: 50; background: #fff;
  border-bottom: 1px solid var(--line);
  box-shadow: 0 1px 8px rgba(0,0,0,.05);
}
.header-in { display: flex; align-items: center; justify-content: space-between; min-height: 64px; gap: 16px; }
.logo img { height: 40px; width: auto; }
.nav-btn { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-btn span { display: block; width: 22px; height: 2px; background: var(--ink); margin: 5px 0; transition: .2s; }
.main-nav ul { list-style: none; display: flex; gap: 4px; }
.main-nav > ul > li { position: relative; }
.main-nav > ul > li > a {
  display: block; padding: 20px 14px; color: var(--ink); font-weight: 600; font-size: .95rem;
}
.main-nav > ul > li > a:hover { color: var(--green); text-decoration: none; }
.main-nav .sub {
  display: none; position: absolute; top: 100%; left: 0; min-width: 220px; background: #fff;
  border: 1px solid var(--line); border-radius: 0 0 var(--radius) var(--radius);
  box-shadow: 0 8px 20px rgba(0,0,0,.08); padding: 6px 0; flex-direction: column;
}
.main-nav > ul > li:hover .sub { display: flex; }
.main-nav .sub a { display: block; padding: 9px 18px; color: var(--ink); font-size: .92rem; }
.main-nav .sub a:hover { background: var(--bg-alt); color: var(--green); text-decoration: none; }

/* hero */
.hero {
  background: linear-gradient(120deg, var(--green-dark), var(--green) 65%, #14976a);
  color: #fff; padding: 76px 0; text-align: center;
}
.hero h1 { color: #fff; max-width: 820px; margin: 0 auto 14px; }
.hero p { max-width: 720px; margin: 0 auto; opacity: .95; }
.hero-cta { margin-top: 26px; }
.btn {
  display: inline-block; background: var(--green); color: #fff; font-weight: 600;
  padding: 12px 26px; border-radius: 8px; transition: .15s;
}
.btn:hover { background: var(--green-dark); color: #fff; text-decoration: none; }
.btn.ghost { background: transparent; border: 2px solid currentColor; color: inherit; }
.hero .btn { background: #fff; color: var(--green-dark); }
.hero .btn:hover { background: #e8f3ee; }
.hero .btn.ghost { background: transparent; border-color: #fff; color: #fff; }
.btn.ghost:hover { opacity: .8; }

/* sections & grids */
.section { padding: 44px 0; }
.section.alt { background: var(--bg-alt); }
main > .section:first-child { padding-top: 10px; }
.grid4, .grid3 { list-style: none; display: grid; gap: 20px; margin: 18px 0; }
.grid4 { grid-template-columns: repeat(4, 1fr); }
.grid3 { grid-template-columns: repeat(3, 1fr); }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; transition: .18s;
}
.card a { display: block; color: inherit; }
.card:hover { transform: translateY(-3px); box-shadow: 0 10px 24px rgba(0,0,0,.09); text-decoration: none; }
.card img { width: 100%; aspect-ratio: 4/3; object-fit: cover; }
.card-t { display: block; padding: 12px 14px; font-weight: 600; font-size: .95rem; }
.news-card time { display: block; padding: 0 14px 12px; color: var(--muted); font-size: .85rem; }
.adv { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }

/* breadcrumbs */
.crumbs { padding: 14px 0 4px; font-size: .85rem; color: var(--muted); }
.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
.crumbs li + li::before { content: "›"; margin-right: 6px; color: #b7c4be; }

/* product detail */
.product-in { display: grid; grid-template-columns: minmax(0, 460px) 1fr; gap: 30px; margin: 20px 0; }
.product-img { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.product-img img { width: 100%; }
.spec-table { width: 100%; border-collapse: collapse; margin: 10px 0; font-size: .95rem; }
.spec-table th, .spec-table td { border: 1px solid var(--line); padding: 9px 12px; text-align: left; vertical-align: top; }
.spec-table th { background: var(--bg-alt); width: 140px; font-weight: 600; }
.cta-row { margin: 16px 0; display: flex; gap: 12px; flex-wrap: wrap; }
.product-content, .prose { max-width: 860px; }
.product-content img, .prose img { border-radius: 8px; margin: 14px auto; }
.product-content h2, .prose h2 { margin-top: 30px; }

/* news */
.news-meta { color: var(--muted); font-size: .9rem; margin-bottom: 16px; }
.news-hero { border-radius: var(--radius); margin: 16px 0; }

/* contact */
.contact-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 26px; margin-top: 18px; }
.contact-card { background: var(--bg-alt); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; }
.contact-card img { margin: 0 auto; }

/* footer */
.site-footer { background: #122019; color: #c9d6cf; padding: 46px 0 0; font-size: .92rem; }
.foot-in { display: grid; grid-template-columns: 2fr 1fr 1fr 1.6fr; gap: 30px; }
.site-footer h3 { color: #fff; font-size: 1rem; margin: 0 0 12px; }
.site-footer ul { list-style: none; }
.site-footer li { margin: 6px 0; }
.site-footer a { color: #9fd4b8; }
.copyright { border-top: 1px solid #24382e; margin-top: 34px; padding: 18px 20px; text-align: center; color: #7d9187; }

/* responsive */
@media (max-width: 900px) {
  .grid4 { grid-template-columns: repeat(2, 1fr); }
  .grid3 { grid-template-columns: repeat(2, 1fr); }
  .product-in, .contact-grid { grid-template-columns: 1fr; }
  .foot-in { grid-template-columns: 1fr 1fr; }
  .nav-btn { display: block; }
  .main-nav { display: none; width: 100%; }
  body.nav-open .main-nav { display: block; }
  .header-in { flex-wrap: wrap; }
  .main-nav ul { flex-direction: column; width: 100%; padding-bottom: 10px; }
  .main-nav > ul > li > a { padding: 12px 4px; border-bottom: 1px solid var(--line); }
  .main-nav .sub { position: static; display: flex; box-shadow: none; border: 0; padding-left: 16px; }
}
@media (max-width: 560px) {
  .grid4, .grid3, .foot-in { grid-template-columns: 1fr; }
}