/* Chengbang Energy — site styles (v1, local review) */
* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --brand: #0a4d8c;
  --brand-dark: #062f56;
  --accent: #f5a623;
  --text: #1d2733;
  --muted: #5a6a7a;
  --bg: #ffffff;
  --bg-alt: #f2f6fa;
  --border: #dde5ec;
}
body { font-family: "Helvetica Neue", Arial, "PingFang SC", sans-serif; color: var(--text); background: var(--bg); line-height: 1.65; }
img { max-width: 100%; display: block; }
a { color: var(--brand); text-decoration: none; }
.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

/* Header / nav */
.site-header { background: var(--brand-dark); color: #fff; position: sticky; top: 0; z-index: 10; }
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { color: #fff; font-weight: 700; font-size: 20px; letter-spacing: .5px; }
.logo span { color: var(--accent); }
.main-nav a { color: #dbe7f2; margin-left: 16px; font-size: 14.5px; padding: 6px 2px; border-bottom: 2px solid transparent; white-space: nowrap; }
.main-nav a:hover, .main-nav a.active { color: #fff; border-bottom-color: var(--accent); }

/* Hero */
.hero { background: linear-gradient(135deg, var(--brand-dark) 0%, var(--brand) 70%); color: #fff; padding: 88px 0 76px; }
.hero h1 { font-size: 42px; line-height: 1.2; max-width: 760px; }
.hero p { margin: 20px 0 32px; font-size: 19px; color: #cfe0ef; max-width: 680px; }
.btn { display: inline-block; padding: 13px 30px; border-radius: 4px; font-weight: 600; font-size: 16px; margin-right: 12px; }
.btn-primary { background: var(--accent); color: #1d2733; }
.btn-outline { border: 2px solid #9db8cf; color: #fff; }
.btn:hover { opacity: .9; }

/* Trust bar */
.trust { background: var(--bg-alt); border-bottom: 1px solid var(--border); padding: 22px 0; }
.trust .container { display: flex; flex-wrap: wrap; gap: 18px 44px; justify-content: center; }
.trust-item { text-align: center; }
.trust-item b { display: block; font-size: 24px; color: var(--brand); }
.trust-item span { font-size: 13px; color: var(--muted); }

/* Sections */
section { padding: 64px 0; }
section.alt { background: var(--bg-alt); }
.section-title { font-size: 30px; margin-bottom: 8px; }
.section-sub { color: var(--muted); margin-bottom: 36px; max-width: 720px; }

/* Cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; }
.card { background: #fff; border: 1px solid var(--border); border-radius: 10px; overflow: hidden; transition: box-shadow .2s; }
.card:hover { box-shadow: 0 6px 20px rgba(10,77,140,.12); }
.card img { height: 190px; width: 100%; object-fit: cover; }
.card-body { padding: 20px; }
.card-body h3 { font-size: 18px; margin-bottom: 8px; }
.card-body p { font-size: 14.5px; color: var(--muted); }
.card-body a { display: inline-block; margin-top: 12px; font-weight: 600; font-size: 14px; }

/* Feature list */
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 28px; }
.feature h3 { font-size: 17px; margin: 10px 0 6px; }
.feature p { color: var(--muted); font-size: 14.5px; }
.feature .num { width: 40px; height: 40px; border-radius: 50%; background: var(--brand); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: 700; }

/* Split layout */
section h3 { font-size: 19px; margin-bottom: 10px; }
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; }
.split img { border-radius: 10px; box-shadow: 0 4px 16px rgba(0,0,0,.10); }
@media (max-width: 800px) { .split { grid-template-columns: 1fr; } .hero h1 { font-size: 30px; } }

/* Tables */
table.spec { width: 100%; border-collapse: collapse; margin: 20px 0; font-size: 14.5px; }
table.spec th, table.spec td { border: 1px solid var(--border); padding: 10px 14px; text-align: left; }
table.spec th { background: var(--bg-alt); color: var(--brand-dark); }
table.spec td:first-child { font-weight: 600; width: 30%; }

/* CTA band */
.cta-band { background: var(--brand); color: #fff; text-align: center; padding: 56px 0; }
.cta-band h2 { margin-bottom: 10px; }
.cta-band p { color: #cfe0ef; margin-bottom: 24px; }

/* Footer */
.site-footer { background: var(--brand-dark); color: #9fb4c8; padding: 44px 0 28px; font-size: 14px; }
.site-footer .cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 28px; margin-bottom: 28px; }
.site-footer h4 { color: #fff; margin-bottom: 10px; font-size: 15px; }
.site-footer a { color: #cfe0ef; }
.copyright { border-top: 1px solid #1c4a77; padding-top: 18px; text-align: center; font-size: 13px; color: #7a93ab; }

/* Page hero (inner pages) */
.page-hero { background: linear-gradient(135deg, var(--brand-dark), var(--brand)); color: #fff; padding: 56px 0; }
.page-hero h1 { font-size: 34px; }
.page-hero p { color: #cfe0ef; margin-top: 10px; max-width: 720px; }

.badge { display: inline-block; background: #eaf2fa; color: var(--brand); border-radius: 20px; padding: 4px 14px; font-size: 13px; margin: 0 8px 8px 0; }
.note-tbc { color: #b06a00; font-size: 13px; }

/* Product card placeholder image (used only when no compliant photo is available; kept in production) */
.card-ph { height: 190px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px;
  background: linear-gradient(135deg, var(--brand-dark), var(--brand)); color: #cfe0ef; }
.card-ph b { color: #fff; font-size: 15px; letter-spacing: .5px; }
.card-ph span { font-size: 12px; opacity: .8; }

/* Article / news pages */
.article-wrap { max-width: 760px; margin: 0 auto; padding: 0 24px; }
.article-meta { color: var(--muted); font-size: 13.5px; margin: 10px 0 28px; }
.article-body h2 { font-size: 23px; margin: 36px 0 12px; }
.article-body h3 { font-size: 18px; margin: 26px 0 8px; }
.article-body p { margin: 0 0 16px; font-size: 16px; }
.article-body ul, .article-body ol { margin: 0 0 18px 22px; }
.article-body li { margin-bottom: 8px; font-size: 16px; }
.article-body table.spec { font-size: 15px; }
.article-cta { background: var(--bg-alt); border: 1px solid var(--border); border-left: 4px solid var(--accent);
  border-radius: 8px; padding: 20px 22px; margin: 32px 0; }
.article-cta h3 { margin-top: 0; }
.card-tag { display: inline-block; background: #eaf2fa; color: var(--brand); border-radius: 4px;
  padding: 2px 8px; font-size: 12px; margin-bottom: 8px; }

/* Article table of contents */
html { scroll-behavior: smooth; }
.article-body h2 { scroll-margin-top: 84px; }
.toc { background: var(--bg-alt); border: 1px solid var(--border); border-radius: 8px;
  padding: 16px 22px 12px; margin: 0 0 30px; }
.toc-title { font-size: 13px; letter-spacing: .8px; text-transform: uppercase; color: var(--muted);
  margin: 0 0 8px; font-weight: 700; }
.toc ol { margin: 0 0 0 20px; }
.toc li { margin-bottom: 6px; font-size: 15px; }
.toc a { color: var(--brand); }

/* Previous / next article */
.prevnext { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin: 40px 0 0; }
.prevnext a { display: block; border: 1px solid var(--border); border-radius: 8px; padding: 14px 16px;
  background: #fff; transition: border-color .15s; }
.prevnext a:hover { border-color: var(--brand); }
.prevnext .pn-label { display: block; font-size: 12px; color: var(--muted); text-transform: uppercase;
  letter-spacing: .5px; margin-bottom: 5px; }
.prevnext .pn-ttl { font-size: 15px; color: var(--brand); font-weight: 600; }
.prevnext a.next { text-align: right; }
@media (max-width: 640px) { .prevnext { grid-template-columns: 1fr; } .prevnext a.next { text-align: left; } }

/* Product index */
.prodcat { margin: 44px 0 0; border-top: 1px solid var(--border); padding-top: 26px; }
.prodcat h2 { font-size: 20px; margin: 0 0 6px; }
.prodcat > p { font-size: 14px; color: var(--muted); margin: 0 0 16px; }
.prodcat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(238px, 1fr)); gap: 14px; }
a.prodcat-item { display: flex; gap: 12px; align-items: center; border: 1px solid var(--border);
  border-radius: 8px; padding: 9px 11px; background: #fff; transition: border-color .15s; }
a.prodcat-item:hover { border-color: var(--brand); }
a.prodcat-item img { width: 62px; height: 46px; object-fit: cover; border-radius: 5px; flex: 0 0 auto; }
a.prodcat-item b { display: block; font-size: 14.5px; color: var(--brand); }
a.prodcat-item i { display: block; font-style: normal; font-size: 12.5px; color: var(--muted); }

/* ── WhatsApp entry (header) ── */
.wa-btn { display: inline-flex; align-items: center; gap: 7px; background: #25d366; color: #fff !important;
  padding: 8px 15px; border-radius: 4px; font-size: 14px; font-weight: 600; white-space: nowrap; }
.wa-btn:hover { opacity: .9; }
.wa-btn svg { width: 17px; height: 17px; fill: currentColor; flex: 0 0 auto; }

/* ── WhatsApp large button (contact section) ── */
.wa-btn-lg { display: inline-flex; align-items: center; gap: 9px; background: #25d366; color: #fff !important;
  padding: 13px 26px; border-radius: 4px; font-size: 16px; font-weight: 600; margin-top: 16px; }
.wa-btn-lg:hover { opacity: .9; }
.wa-btn-lg svg { width: 20px; height: 20px; fill: currentColor; }

/* ── Inquiry form ── */
.inquiry-form label { display: block; margin-bottom: 13px; font-size: 14px; font-weight: 600; color: var(--brand-dark); }
.inquiry-form input, .inquiry-form select, .inquiry-form textarea {
  width: 100%; margin-top: 5px; padding: 10px 12px; border: 1px solid var(--border); border-radius: 5px;
  font-size: 15px; font-family: inherit; color: var(--text); background: #fff; font-weight: 400; }
.inquiry-form input:focus, .inquiry-form select:focus, .inquiry-form textarea:focus {
  outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px rgba(10,77,140,.10); }
.inquiry-form textarea { resize: vertical; min-height: 92px; }
.inquiry-form .req { color: #c0392b; }
.form-note { font-size: 13px; color: var(--muted); margin-top: 10px; line-height: 1.55; }
.form-fallback { display: none; margin-top: 14px; padding: 14px 16px; border: 1px solid #f0d9a8;
  background: #fdf7e8; border-radius: 6px; font-size: 13.5px; line-height: 1.6; }
.form-fallback b { color: #8a5a00; }
.form-fallback .copy-btn { margin-top: 9px; padding: 7px 15px; border: 1px solid var(--brand);
  background: #fff; color: var(--brand); border-radius: 4px; font-size: 13px; font-weight: 600; cursor: pointer; }
.form-fallback .copy-btn:hover { background: var(--brand); color: #fff; }

/* ── Mobile layout (horizontal nav scroll + header wrap) ── */
@media (max-width: 800px) {
  .site-header .container { flex-wrap: wrap; height: auto; padding: 11px 20px 0; row-gap: 10px; }
  .logo { font-size: 17px; order: 1; }
  .wa-btn { order: 2; margin-left: auto; padding: 6px 12px; font-size: 13px; }
  .main-nav { order: 3; width: 100%; overflow-x: auto; white-space: nowrap;
    -webkit-overflow-scrolling: touch; padding-bottom: 9px; scrollbar-width: none; }
  .main-nav::-webkit-scrollbar { display: none; }
  .main-nav a { margin-left: 0; margin-right: 20px; font-size: 14.5px; }
  section { padding: 46px 0; }
  .section-title { font-size: 25px; }
  .page-hero h1 { font-size: 27px; }
  .trust .container { gap: 14px 26px; }
  .hero { padding: 60px 0 52px; }
  .card img { height: 165px; }
}
@media (max-width: 640px) {
  .article-wrap { padding: 0 18px; }
  .article-body h2 { font-size: 20px; }
  .article-body p, .article-body li { font-size: 15.5px; }
  table.spec { font-size: 13.5px; }
  table.spec th, table.spec td { padding: 8px 10px; }
}

/* ── Certification documents ── */
.cert-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 16px; margin-top: 20px; }
.cert-item { margin: 0; border: 1px solid var(--border); border-radius: 8px; background: #fff; overflow: hidden; }
.cert-item img { width: 100%; aspect-ratio: 3 / 4; object-fit: cover; object-position: top; display: block; }
.cert-item figcaption { padding: 10px 12px 12px; font-size: 13px; color: var(--muted); border-top: 1px solid var(--border); }
.cert-item b { display: block; font-size: 15px; color: var(--brand); margin-bottom: 2px; }

/* ── WhatsApp floating button (all pages) ── */
.wa-float{position:fixed;right:18px;bottom:18px;z-index:9000;width:56px;height:56px;border-radius:50%;
  background:#25d366;display:flex;align-items:center;justify-content:center;
  box-shadow:0 6px 18px rgba(0,0,0,.28);transition:transform .15s}
.wa-float:hover{transform:scale(1.07)}
.wa-float svg{width:31px;height:31px;fill:#fff}
@media (max-width:640px){.wa-float{width:52px;height:52px;right:14px;bottom:14px}}

/* ── Inline inquiry form inside CTA blocks ── */
.cta-band .cta-form{background:#fff;border-radius:10px;padding:22px 24px;max-width:620px;
  margin:22px auto 0;text-align:left}
.article-cta .cta-form{background:transparent;padding:0;margin:14px 0 0;max-width:none}
.cta-form h3{margin:0 0 12px;font-size:17px;color:#0a4d8c}