/* ============================================================
   SWD — Foshan Shengweida New Materials
   Single-page marketing site stylesheet
   Palette: green #2E8B57 / #3DA35D · deep blue #123B6D / #1A4B8C
   ============================================================ */

:root {
  --green: #2E8B57;
  --green-light: #3DA35D;
  --green-bg: #EAF4EE;
  --blue: #123B6D;
  --blue-mid: #1A4B8C;
  --ink: #1E2733;
  --ink-soft: #4A5768;
  --line: #E2E8EF;
  --bg: #FFFFFF;
  --bg-alt: #F5F7FA;
  --whatsapp: #25D366;
  --radius: 12px;
  --shadow: 0 6px 24px rgba(18, 59, 109, .08);
  --shadow-hover: 0 10px 32px rgba(18, 59, 109, .14);
  --maxw: 1140px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--green); text-decoration: none; }
a:hover { color: var(--blue-mid); }

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

/* Accessibility */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--blue);
  color: #fff;
  padding: 10px 18px;
  z-index: 200;
}
.skip-link:focus { left: 12px; top: 12px; color: #fff; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 13px 28px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 16px;
  line-height: 1.2;
  border: 2px solid transparent;
  cursor: pointer;
  transition: background .2s, color .2s, border-color .2s, transform .15s;
  text-align: center;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--green); color: #fff; }
.btn-primary:hover { background: var(--green-light); color: #fff; }
.btn-outline { border-color: var(--blue); color: var(--blue); background: transparent; }
.btn-outline:hover { background: var(--blue); color: #fff; }
.btn-whatsapp { background: var(--whatsapp); color: #fff; }
.btn-whatsapp:hover { background: #1FBE5A; color: #fff; }
.btn-small { padding: 9px 18px; font-size: 14.5px; }
.btn-block { display: block; width: 100%; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 72px;
}
.brand img { height: 46px; width: auto; }
.main-nav { display: flex; gap: 26px; margin-left: auto; }
.main-nav a {
  color: var(--ink);
  font-weight: 600;
  font-size: 15px;
  padding: 6px 0;
  border-bottom: 2px solid transparent;
}
.main-nav a:hover { color: var(--green); border-bottom-color: var(--green); }
.header-cta { padding: 10px 20px; font-size: 15px; }

.nav-toggle {
  display: none;
  background: none;
  border: 0;
  width: 44px;
  height: 44px;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  align-items: center;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2.5px;
  background: var(--blue);
  border-radius: 2px;
  transition: transform .25s, opacity .25s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(135deg, var(--blue) 0%, var(--blue-mid) 55%, var(--green) 130%);
  color: #fff;
  padding: 88px 0 80px;
}
.hero-inner {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  gap: 48px;
  align-items: center;
}
.hero-kicker {
  text-transform: uppercase;
  letter-spacing: .12em;
  font-size: 13px;
  font-weight: 700;
  color: #A9D8BC;
  margin-bottom: 14px;
}
.hero h1 {
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.2;
  font-weight: 800;
  margin-bottom: 18px;
}
.hero-sub { font-size: 17.5px; color: #DCE7F3; max-width: 56ch; margin-bottom: 22px; }
.hero-badges {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}
.hero-badges li {
  background: rgba(255, 255, 255, .14);
  border: 1px solid rgba(255, 255, 255, .35);
  border-radius: 999px;
  padding: 6px 16px;
  font-size: 14px;
  font-weight: 600;
}
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 14px; }
.hero-cta .btn-outline { border-color: #fff; color: #fff; }
.hero-cta .btn-outline:hover { background: #fff; color: var(--blue); }
.hero-note { font-size: 13.5px; color: #B9CBDD; }
.hero-media img {
  border-radius: var(--radius);
  box-shadow: 0 18px 44px rgba(0, 0, 0, .28);
}

/* ---------- Sections ---------- */
.section { padding: 84px 0; scroll-margin-top: 80px; }
.section-alt { background: var(--bg-alt); }
.section-kicker {
  text-transform: uppercase;
  letter-spacing: .14em;
  font-size: 13px;
  font-weight: 700;
  color: var(--green);
  margin-bottom: 8px;
}
.section h2 {
  font-size: clamp(24px, 3vw, 34px);
  color: var(--blue);
  line-height: 1.25;
  margin-bottom: 16px;
  font-weight: 800;
}
.section-lede { color: var(--ink-soft); max-width: 78ch; margin-bottom: 40px; font-size: 17px; }
.sub-heading {
  color: var(--blue);
  font-size: 22px;
  margin: 56px 0 22px;
  padding-top: 12px;
}

/* ---------- Product cards ---------- */
.core-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}
.product-card {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: box-shadow .25s, transform .25s;
}
.product-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
.hero-product { border-top: 4px solid var(--green); }
.flag {
  align-self: flex-start;
  background: var(--green-bg);
  color: var(--green);
  font-size: 12.5px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  padding: 5px 12px;
  border-radius: 999px;
}
.product-media img { border-radius: 8px; max-height: 260px; object-fit: cover; width: 100%; }
.product-body h3 { color: var(--blue); font-size: 20px; line-height: 1.3; margin-bottom: 10px; }
.product-desc { color: var(--ink-soft); font-size: 15px; }
.product-body ul { list-style: none; }
.product-body ul li {
  position: relative;
  padding-left: 22px;
  margin-bottom: 8px;
  color: var(--ink-soft);
  font-size: 15px;
}
.product-body ul li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 700;
}
.data-list li strong { color: var(--ink); }
.dosage {
  font-size: 14px;
  color: var(--blue-mid);
  background: var(--bg-alt);
  border-left: 3px solid var(--green);
  padding: 10px 14px;
  border-radius: 0 8px 8px 0;
}
.product-body .btn { align-self: flex-start; margin-top: auto; }

/* ---------- Mini grid ---------- */
.mini-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.mini-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
  transition: box-shadow .25s, transform .25s;
}
.mini-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
.mini-card img { border-radius: 8px; margin-bottom: 12px; height: 130px; object-fit: cover; width: 100%; }
.mini-card h4 { color: var(--blue); font-size: 16px; margin-bottom: 8px; line-height: 1.35; }
.mini-card p { font-size: 14px; color: var(--ink-soft); }

/* ---------- Applications ---------- */
.app-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 48px;
}
.app-card {
  background: #fff;
  border: 1px solid var(--line);
  border-left: 4px solid var(--green);
  border-radius: var(--radius);
  padding: 22px 20px;
  box-shadow: var(--shadow);
  transition: box-shadow .25s, transform .25s;
}
.app-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
.app-card h3 { color: var(--blue); font-size: 16.5px; margin-bottom: 8px; line-height: 1.35; }
.app-card p { font-size: 14px; color: var(--ink-soft); }

.field-proof {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
  background: var(--blue);
  color: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  padding-right: 40px;
}
.field-proof img { width: 100%; height: 100%; object-fit: cover; min-height: 260px; }
.field-proof h3 { font-size: 22px; margin-bottom: 12px; }
.field-proof p { color: #CFDDEB; font-size: 15.5px; }

/* ---------- Compliance ---------- */
.compliance {
  display: grid;
  grid-template-columns: 1.1fr .9fr;
  gap: 48px;
  align-items: center;
}
.compliance h2 { margin-bottom: 14px; }
.compliance p { color: var(--ink-soft); margin-bottom: 14px; }
.fineprint {
  font-size: 13.5px;
  color: var(--blue-mid);
  font-style: italic;
}
.tech-list { list-style: none; margin-top: 18px; }
.tech-list li {
  position: relative;
  padding-left: 26px;
  margin-bottom: 10px;
  color: var(--ink-soft);
  font-size: 15px;
}
.tech-list li::before {
  content: "●";
  position: absolute;
  left: 0;
  color: var(--green);
  font-size: 12px;
  top: 3px;
}
.compliance-media img { border-radius: var(--radius); box-shadow: var(--shadow); }

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}
.about-photo img { border-radius: var(--radius); box-shadow: var(--shadow); }
.about-photo figcaption {
  font-size: 13.5px;
  color: var(--ink-soft);
  margin-top: 10px;
  text-align: center;
}
.about-points {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px 32px;
}
.about-points li {
  position: relative;
  padding-left: 26px;
  color: var(--ink-soft);
  font-size: 15.5px;
}
.about-points li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 700;
}

/* ---------- Contact ---------- */
.contact-section { background: var(--green-bg); }
.contact-grid {
  display: grid;
  grid-template-columns: .95fr 1.05fr;
  gap: 48px;
  align-items: start;
}
.contact-info p { color: var(--ink-soft); margin-bottom: 18px; }
.contact-lines { list-style: none; margin: 22px 0 28px; }
.contact-lines li {
  padding: 10px 0;
  border-bottom: 1px solid rgba(18, 59, 109, .12);
  font-size: 15.5px;
  color: var(--ink);
}
.contact-lines .label {
  display: inline-block;
  min-width: 140px;
  font-weight: 700;
  color: var(--blue);
}
.contact-form {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px;
}
.form-row { margin-bottom: 16px; }
.form-row.two { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-row label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--blue);
  margin-bottom: 6px;
}
.form-row input,
.form-row select,
.form-row textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--line);
  border-radius: 8px;
  font-size: 15px;
  font-family: inherit;
  color: var(--ink);
  background: #fff;
  transition: border-color .2s, box-shadow .2s;
}
.form-row input:focus,
.form-row select:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--green);
  box-shadow: 0 0 0 3px rgba(46, 139, 87, .15);
}
.form-row input.invalid,
.form-row textarea.invalid { border-color: #C0392B; }
.form-hint { font-size: 13px; color: var(--ink-soft); margin-top: 12px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--blue); color: #CFDDEB; padding-top: 56px; }
.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
}
.footer-brand img { height: 40px; width: auto; margin-bottom: 14px; filter: brightness(0) invert(1); }
.footer-brand p { font-size: 14.5px; max-width: 34ch; }
.footer-nav { display: flex; flex-direction: column; gap: 10px; }
.footer-nav a { color: #CFDDEB; font-size: 15px; }
.footer-nav a:hover { color: #fff; }
.footer-contact p { font-size: 14.5px; margin-bottom: 8px; }
.footer-contact a { color: #CFDDEB; }
.footer-contact a:hover { color: #fff; }
.footer-legal {
  border-top: 1px solid rgba(255, 255, 255, .15);
  padding: 18px 24px;
  font-size: 13px;
}

/* ---------- WhatsApp float ---------- */
.whatsapp-float {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 90;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--whatsapp);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 24px rgba(37, 211, 102, .45);
  transition: transform .2s;
}
.whatsapp-float:hover { transform: scale(1.08); color: #fff; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .hero-inner, .compliance, .contact-grid, .field-proof { grid-template-columns: 1fr; }
  .core-grid { grid-template-columns: 1fr; }
  .mini-grid { grid-template-columns: repeat(2, 1fr); }
  .app-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid { grid-template-columns: 1fr; }
  .about-points { grid-template-columns: 1fr; }
  .field-proof { padding-right: 0; padding-bottom: 32px; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .hero { padding: 64px 0 56px; }
  .section { padding: 60px 0; }
}

@media (max-width: 820px) {
  .nav-toggle { display: flex; margin-left: auto; }
  .header-cta { display: none; }
  .main-nav {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    gap: 0;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
    max-height: 0;
    overflow: hidden;
    transition: max-height .3s ease;
    margin-left: 0;
  }
  .main-nav.open { max-height: 320px; }
  .main-nav a {
    padding: 14px 24px;
    border-bottom: 1px solid var(--bg-alt);
    border-left: 3px solid transparent;
  }
  .main-nav a:hover { border-bottom-color: var(--bg-alt); border-left-color: var(--green); }
}

@media (max-width: 560px) {
  .mini-grid { grid-template-columns: 1fr; }
  .app-grid { grid-template-columns: 1fr; }
  .form-row.two { grid-template-columns: 1fr; }
  .contact-lines .label { display: block; min-width: 0; margin-bottom: 2px; }
  .contact-form { padding: 24px 20px; }
}