/* GreenEng Guide — static site theme
   Palette: primary green #2d6a4f, dark #1a1a2e, paper #f8f9fa */

:root {
  --green: #2d6a4f;
  --green-dark: #1b4332;
  --dark: #1a1a2e;
  --paper: #f8f9fa;
  --ink: #2b2b2b;
  --muted: #666677;
  --border: #e3e6e8;
  --radius: 10px;
  --maxw: 1152px;
  --contentw: 46rem;
  --cat-env: #2d6a4f;
  --cat-battery: #d97706;
  --cat-plant: #2563eb;
  --cat-comp: #7c3aed;
  --cat-ai: #0891b2;
  --cat-insights: #be185d;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC",
    "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.7;
  font-size: 16px;
}

a { color: var(--green); text-decoration: none; }
a:hover { color: var(--green-dark); text-decoration: underline; }

/* ---------- Header ---------- */
.site-header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
  height: 60px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.logo {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--dark);
  white-space: nowrap;
}
.logo .leaf { color: var(--green); }
.logo:hover { text-decoration: none; }

.main-nav {
  display: flex;
  gap: 4px;
  flex: 1;
  flex-wrap: wrap;
  align-items: center;
}
.main-nav a {
  color: #444;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 6px 10px;
  border-radius: 6px;
  white-space: nowrap;
}
.main-nav a:hover { background: #eef4f0; color: var(--green-dark); text-decoration: none; }
.main-nav a.active { background: var(--green); color: #fff; }

.search-box {
  position: relative;
  margin-left: auto;
}
.search-box input {
  width: 170px;
  padding: 8px 12px 8px 32px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 0.9rem;
  background: #f5f6f7 url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%23666' stroke-width='2'%3E%3Ccircle cx='11' cy='11' r='7'/%3E%3Cpath d='m21 21-4-4'/%3E%3C/svg%3E") no-repeat 12px center;
  transition: width 0.2s;
}
.search-box input:focus { outline: none; width: 220px; border-color: var(--green); background-color: #fff; }

/* ---------- Layout ---------- */
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
.content-column { max-width: var(--contentw); margin: 0 auto; padding: 0 20px; }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(160deg, #1b4332 0%, #2d6a4f 60%, #3f8a68 100%);
  color: #fff;
  padding: 64px 0 56px;
}
.hero h1 { margin: 0 0 12px; font-size: 2.1rem; line-height: 1.25; }
.hero p { margin: 0 0 24px; font-size: 1.05rem; color: #d9e8df; max-width: 620px; }
.hero-stats { display: flex; gap: 28px; flex-wrap: wrap; }
.hero-stats .stat { display: flex; flex-direction: column; }
.hero-stats .num { font-size: 1.5rem; font-weight: 800; }
.hero-stats .lbl { font-size: 0.82rem; color: #b9d4c4; }

/* ---------- Category chips ---------- */
.chip {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  background: #eef4f0;
  color: var(--green-dark);
}
.chip:hover { text-decoration: none; filter: brightness(0.95); }
.cat-environmental-engineering { background: rgba(45,106,79,.12); color: var(--cat-env); }
.cat-lithium-battery { background: rgba(217,119,6,.12); color: var(--cat-battery); }
.cat-plant-design-cad { background: rgba(37,99,235,.10); color: var(--cat-plant); }
.cat-environmental-compliance { background: rgba(124,58,237,.10); color: var(--cat-comp); }
.cat-ai-digital { background: rgba(8,145,178,.12); color: var(--cat-ai); }
.cat-industry-insights { background: rgba(190,24,93,.12); color: var(--cat-insights); }

/* ---------- Cards grid ---------- */
.section-title {
  font-size: 1.35rem;
  margin: 44px 0 16px;
  color: var(--dark);
}
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 18px;
}
.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: box-shadow 0.15s, transform 0.15s;
}
.card:hover { box-shadow: 0 6px 18px rgba(27,67,50,.10); transform: translateY(-2px); }
.card h3 { margin: 0; font-size: 1.05rem; line-height: 1.4; }
.card h3 a { color: var(--dark); }
.card h3 a:hover { color: var(--green); text-decoration: none; }
.card .excerpt {
  margin: 0;
  font-size: 0.88rem;
  color: var(--muted);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card .meta { font-size: 0.8rem; color: #999; }

/* ---------- Post page ---------- */
.post-header { padding: 40px 0 8px; }
.post-header .breadcrumbs { font-size: 0.85rem; color: var(--muted); margin-bottom: 14px; }
.post-header h1 { font-size: 1.9rem; line-height: 1.3; margin: 0 0 14px; color: var(--dark); }
.post-meta { display: flex; gap: 14px; align-items: center; flex-wrap: wrap; font-size: 0.88rem; color: #888; }
.post-body {
  font-size: 1.02rem;
  line-height: 1.8;
  padding-bottom: 56px;
}
.post-body h2 { font-size: 1.35rem; margin: 2.2em 0 0.6em; color: var(--dark); }
.post-body h3 { font-size: 1.12rem; margin: 1.8em 0 0.5em; }
.post-body p { margin: 1em 0; }
.post-body ul, .post-body ol { padding-left: 1.4em; }
.post-body li { margin: 0.35em 0; }
.post-body img { max-width: 100%; border-radius: 8px; }
.post-body table { border-collapse: collapse; width: 100%; margin: 1.2em 0; font-size: 0.92rem; }
.post-body th, .post-body td { border: 1px solid var(--border); padding: 8px 12px; text-align: left; }
.post-body th { background: #eef4f0; }
.post-body blockquote {
  margin: 1.2em 0;
  padding: 4px 18px;
  border-left: 4px solid var(--green);
  background: #eef4f0;
  border-radius: 0 8px 8px 0;
  color: #3d5148;
}
.post-body code {
  background: #eef1f3;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: ui-monospace, Consolas, "Courier New", monospace;
}
.post-body pre {
  background: var(--dark);
  color: #d8e0e8;
  padding: 16px 18px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.6;
}
.post-body pre code { background: none; padding: 0; color: inherit; }

.ad-unit {
  margin: 2.2rem 0;
  text-align: center;
  min-height: 90px;
  background: #fdfdfd;
  border: 1px dashed var(--border);
  border-radius: 8px;
  padding: 8px;
}
.ad-unit-label { font-size: 0.7rem; color: #bbb; letter-spacing: 0.08em; text-transform: uppercase; }

.post-footer {
  border-top: 1px solid var(--border);
  margin-top: 40px;
  padding-top: 20px;
  font-size: 0.9rem;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: space-between;
}

/* ---------- Pagination ---------- */
.pagination { display: flex; gap: 8px; justify-content: center; margin: 36px 0 56px; }
.pagination a, .pagination span {
  padding: 8px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  color: #555;
  font-size: 0.9rem;
}
.pagination a:hover { border-color: var(--green); color: var(--green); text-decoration: none; }
.pagination .current { background: var(--green); border-color: var(--green); color: #fff; }

/* ---------- Special pages ---------- */
.page-body { max-width: var(--contentw); margin: 0 auto; padding: 40px 20px 64px; }
.page-body h1 { color: var(--dark); }
.prod-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px,1fr)); gap: 18px; margin: 24px 0; }
.prod-card { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.prod-card h3 { margin: 0 0 6px; }
.prod-price { font-size: 1.5rem; font-weight: 800; color: var(--green); }
.btn {
  display: inline-block;
  background: var(--green);
  color: #fff;
  padding: 12px 26px;
  border-radius: 8px;
  font-weight: 600;
  border: none;
  cursor: pointer;
}
.btn:hover { background: var(--green-dark); color: #fff; text-decoration: none; }
.btn-outline { background: #fff; color: var(--green); border: 2px solid var(--green); }
.btn-outline:hover { background: #eef4f0; color: var(--green-dark); }

/* ---------- Footer ---------- */
.site-footer { background: var(--dark); color: #b9c2c9; margin-top: 56px; }
.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 40px 20px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 32px;
  font-size: 0.88rem;
}
.site-footer h4 { color: #fff; margin: 0 0 12px; font-size: 0.95rem; }
.site-footer a { color: #b9c2c9; display: block; padding: 3px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #2c2c44;
  padding: 16px 20px;
  text-align: center;
  font-size: 0.8rem;
  color: #7b8490;
}

/* ---------- Search page ---------- */
.search-results .card { margin-bottom: 14px; }

/* ---------- Responsive ---------- */
@media (max-width: 820px) {
  .header-inner { flex-wrap: wrap; height: auto; padding: 10px 16px; gap: 10px; }
  .main-nav { order: 3; width: 100%; overflow-x: auto; flex-wrap: nowrap; padding-bottom: 4px; }
  .hero { padding: 44px 0 40px; }
  .hero h1 { font-size: 1.6rem; }
  .footer-inner { grid-template-columns: 1fr; gap: 24px; }
  .post-header h1 { font-size: 1.5rem; }
}