/* Hengyi Sourcing — Premium Design System */
:root {
  --navy: #0a1628;
  --navy-light: #152238;
  --blue: #1e5fbb;
  --blue-dark: #134b9e;
  --gold: #c8963e;
  --gold-light: #d4a853;
  --white: #ffffff;
  --gray-50: #f8f9fb;
  --gray-100: #f1f4f8;
  --gray-200: #e2e7ef;
  --gray-300: #c9d2e0;
  --gray-400: #8b95a5;
  --gray-600: #4a5568;
  --gray-800: #1a202c;
  --green: #25D366;
  --green-dark: #1da851;
  --shadow-sm: 0 1px 2px rgba(10,22,40,0.06);
  --shadow-md: 0 4px 16px rgba(10,22,40,0.08);
  --shadow-lg: 0 12px 40px rgba(10,22,40,0.12);
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 16px;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--gray-800);
  line-height: 1.65;
  background: var(--white);
  font-size: 16px;
}

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

a { color: var(--blue); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--blue-dark); }

/* ── Header ── */
.site-header {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  padding: 0 24px;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--navy);
  letter-spacing: -0.01em;
  white-space: nowrap;
  line-height: 1.3;
}
.logo span {
  font-weight: 400;
  color: var(--gray-400);
  font-size: 0.75rem;
  display: block;
  letter-spacing: 0;
}

.main-nav { display: flex; gap: 4px; align-items: center; }
.main-nav a {
  color: var(--gray-600);
  font-size: 0.875rem;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.main-nav a:hover { color: var(--navy); background: var(--gray-100); }

.nav-cta {
  background: var(--gold) !important;
  color: var(--white) !important;
  padding: 10px 20px !important;
  font-weight: 600 !important;
  border-radius: var(--radius) !important;
  margin-left: 8px;
}
.nav-cta:hover { background: var(--gold-light) !important; color: var(--white) !important; }

.menu-toggle { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; color: var(--gray-800); padding: 8px; }

@media (max-width: 860px) {
  .menu-toggle { display: block; }
  .main-nav {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 16px;
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow-lg);
    gap: 2px;
  }
  .main-nav.open { display: flex; }
  .nav-cta { margin-left: 0; margin-top: 8px; text-align: center; }
}

/* ── Hero ── */
.hero {
  background: linear-gradient(160deg, #060e1a 0%, var(--navy) 40%, var(--navy-light) 100%);
  color: var(--white);
  padding: 96px 24px 88px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(200,150,62,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(30,95,187,0.06) 0%, transparent 70%);
  pointer-events: none;
}

.hero-inner { max-width: 780px; margin: 0 auto; position: relative; z-index: 1; }

.hero .badge {
  display: inline-block;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  color: var(--gold);
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: 20px;
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.8;
  margin-bottom: 36px;
  line-height: 1.7;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  font-weight: 400;
}

.hero-buttons { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 15px 32px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary { background: var(--gold); color: var(--white); box-shadow: 0 2px 8px rgba(200,150,62,0.3); }
.btn-primary:hover { background: var(--gold-light); color: var(--white); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(200,150,62,0.4); }

.btn-whatsapp { background: var(--green); color: var(--white); box-shadow: 0 2px 8px rgba(37,211,102,0.3); }
.btn-whatsapp:hover { background: var(--green-dark); color: var(--white); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(37,211,102,0.4); }

.btn-outline { background: transparent; color: var(--white); border: 1.5px solid rgba(255,255,255,0.3); }
.btn-outline:hover { border-color: rgba(255,255,255,0.6); color: var(--white); background: rgba(255,255,255,0.04); }

@media (max-width: 640px) {
  .hero { padding: 64px 20px; }
  .hero h1 { font-size: 2rem; }
  .hero p { font-size: 1rem; }
  .btn { padding: 14px 24px; font-size: 0.9rem; }
}

/* ── Sections ── */
.section { padding: 88px 24px; }
.section-alt { background: var(--gray-50); }

.section-inner { max-width: 1140px; margin: 0 auto; }

.section-label {
  display: block;
  text-align: center;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gold);
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 14px;
  text-align: center;
  letter-spacing: -0.01em;
}

.section-subtitle {
  color: var(--gray-400);
  text-align: center;
  margin-bottom: 56px;
  font-size: 1.05rem;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.6;
}

@media (max-width: 640px) {
  .section { padding: 56px 20px; }
  .section-title { font-size: 1.6rem; }
}

/* ── Services Grid ── */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.service-card {
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition);
  position: relative;
}
.service-card:hover {
  box-shadow: var(--shadow-md);
  border-color: transparent;
  transform: translateY(-2px);
}

.service-card .icon {
  width: 52px;
  height: 52px;
  background: var(--gray-50);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.service-card h3 { font-size: 1.05rem; margin-bottom: 10px; color: var(--navy); font-weight: 700; }
.service-card p { color: var(--gray-400); font-size: 0.9rem; line-height: 1.65; }

/* ── Category Tags ── */
.category-tags { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.category-tag {
  background: var(--white);
  border: 1px solid var(--gray-200);
  padding: 11px 22px;
  border-radius: 50px;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--gray-600);
  transition: all var(--transition);
}
.category-tag:hover { border-color: var(--gold); color: var(--gold); background: rgba(200,150,62,0.04); }

/* ── Process ── */
.process-list { max-width: 680px; margin: 0 auto; }

.process-step {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  margin-bottom: 24px;
  padding: 20px 24px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.process-step:hover { box-shadow: var(--shadow-sm); border-color: var(--gray-300); }

.process-step .step-num {
  min-width: 44px;
  height: 44px;
  background: var(--navy);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.process-step h4 { font-size: 0.95rem; color: var(--navy); margin-bottom: 4px; font-weight: 600; }
.process-step p { color: var(--gray-400); font-size: 0.85rem; }

@media (max-width: 640px) {
  .process-step { padding: 16px; }
}

/* ── Trust Grid ── */
.trust-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
}
.trust-item {
  text-align: center;
  padding: 28px 20px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.trust-item:hover { box-shadow: var(--shadow-sm); }
.trust-item .check { color: var(--gold); font-size: 1.4rem; margin-bottom: 10px; }
.trust-item h4 { font-size: 0.9rem; color: var(--navy); font-weight: 600; line-height: 1.4; }

/* ── FAQ ── */
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-item {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  margin-bottom: 10px;
  overflow: hidden;
  transition: all var(--transition);
}
.faq-item:hover { border-color: var(--gray-300); }
.faq-item.open { border-color: var(--gold); box-shadow: var(--shadow-sm); }

.faq-question {
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  background: var(--white);
  border: none;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--navy);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.faq-question::after { content: '+'; font-size: 1.4rem; color: var(--gray-300); font-weight: 400; transition: all var(--transition); }
.faq-item.open .faq-question::after { content: '−'; color: var(--gold); }

.faq-answer { display: none; padding: 0 24px 20px; color: var(--gray-400); font-size: 0.9rem; line-height: 1.7; }
.faq-answer p { margin: 0; }
.faq-item.open .faq-answer { display: block; }

/* ── RFQ Form ── */
.rfq-form {
  max-width: 620px;
  margin: 0 auto;
  background: var(--white);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 44px 40px;
  box-shadow: var(--shadow-md);
}

.rfq-form h3 {
  font-size: 1.4rem;
  color: var(--navy);
  margin-bottom: 8px;
  text-align: center;
  font-weight: 700;
}
.rfq-form .form-subtitle {
  text-align: center;
  color: var(--gray-400);
  font-size: 0.9rem;
  margin-bottom: 32px;
}

.form-row { margin-bottom: 18px; }
.form-row label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--gray-600);
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.form-row input, .form-row textarea, .form-row select {
  width: 100%;
  padding: 13px 16px;
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-family: inherit;
  color: var(--gray-800);
  background: var(--gray-50);
  transition: all var(--transition);
}
.form-row input:focus, .form-row textarea:focus, .form-row select:focus {
  outline: none;
  border-color: var(--gold);
  background: var(--white);
  box-shadow: 0 0 0 3px rgba(200,150,62,0.08);
}

.form-row textarea { min-height: 110px; resize: vertical; }
.form-row .hint { font-size: 0.78rem; color: var(--gray-400); margin-top: 5px; }

.form-row input[type="file"] {
  padding: 10px 0;
  border: none;
  background: none;
  font-size: 0.9rem;
}

.form-submit {
  width: 100%;
  padding: 15px;
  background: var(--gold);
  color: var(--white);
  border: none;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  margin-top: 8px;
  letter-spacing: 0.01em;
}
.form-submit:hover { background: var(--gold-light); box-shadow: 0 4px 16px rgba(200,150,62,0.35); transform: translateY(-1px); }

.form-success {
  display: none;
  text-align: center;
  padding: 20px;
}
.form-success.visible { display: block; }
.form-success .check-icon { font-size: 3rem; margin-bottom: 16px; }
.form-success h4 { font-size: 1.2rem; color: var(--navy); margin-bottom: 8px; }

@media (max-width: 640px) {
  .rfq-form { padding: 28px 20px; }
}

/* ── WhatsApp Float ── */
.whatsapp-float {
  position: fixed;
  bottom: 28px;
  right: 28px;
  background: var(--green);
  color: var(--white);
  border-radius: 50px;
  padding: 14px 22px;
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.88rem;
  box-shadow: 0 6px 24px rgba(37,211,102,0.35);
  z-index: 999;
  transition: all var(--transition);
  letter-spacing: 0.01em;
}
.whatsapp-float:hover { transform: translateY(-3px); color: var(--white); box-shadow: 0 8px 32px rgba(37,211,102,0.45); }
.whatsapp-float .wa-icon { font-size: 1.3rem; }

@media (max-width: 480px) {
  .whatsapp-float { bottom: 16px; right: 12px; padding: 12px 16px; }
  .whatsapp-float .label { display: none; }
}

/* ── Page Hero ── */
.page-hero {
  background: linear-gradient(160deg, #060e1a 0%, var(--navy) 60%);
  color: var(--white);
  padding: 64px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  right: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(200,150,62,0.06) 0%, transparent 70%);
  pointer-events: none;
}
.page-hero h1 { font-size: 2.2rem; font-weight: 800; letter-spacing: -0.02em; margin-bottom: 12px; position: relative; z-index: 1; }
.page-hero p { font-size: 1.05rem; opacity: 0.8; max-width: 600px; margin: 0 auto; position: relative; z-index: 1; line-height: 1.6; }

/* ── Content Area ── */
.content-area { max-width: 780px; margin: 0 auto; }
.content-area h2 { font-size: 1.5rem; color: var(--navy); margin: 40px 0 16px; font-weight: 700; letter-spacing: -0.01em; }
.content-area h3 { font-size: 1.1rem; margin: 28px 0 12px; color: var(--navy); font-weight: 600; }
.content-area p { margin-bottom: 16px; color: var(--gray-600); line-height: 1.7; font-size: 0.95rem; }
.content-area ul, .content-area ol { margin-bottom: 20px; padding-left: 24px; }
.content-area li { margin-bottom: 8px; color: var(--gray-600); font-size: 0.95rem; line-height: 1.6; }
.content-area strong { color: var(--navy); }

/* ── CTA Bar ── */
.cta-bar {
  background: var(--navy);
  padding: 64px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-bar::before {
  content: '';
  position: absolute;
  top: -40%;
  left: -10%;
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(200,150,62,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.cta-bar h3 { font-size: 1.6rem; color: var(--white); margin-bottom: 12px; font-weight: 700; position: relative; }
.cta-bar p { color: rgba(255,255,255,0.7); margin-bottom: 28px; position: relative; font-size: 1rem; }
.cta-bar .btn { margin: 0 6px; position: relative; }

/* ── Footer ── */
.site-footer { background: var(--navy); color: rgba(255,255,255,0.65); padding: 56px 24px 28px; }
.footer-inner { max-width: 1140px; margin: 0 auto; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 36px; }

.footer-col h4 { color: var(--white); font-size: 0.88rem; margin-bottom: 16px; font-weight: 700; letter-spacing: 0.02em; }
.footer-col p, .footer-col a { font-size: 0.85rem; line-height: 2; color: rgba(255,255,255,0.6); }
.footer-col a:hover { color: var(--gold); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 24px;
  text-align: center;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
}

@media (max-width: 768px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
}

/* ── Blog ── */
.blog-card { padding: 28px 0; border-bottom: 1px solid var(--gray-200); }
.blog-card:last-child { border-bottom: none; }
.blog-card h3 { font-size: 1.1rem; margin-bottom: 8px; font-weight: 600; }
.blog-card h3 a { color: var(--navy); }
.blog-card h3 a:hover { color: var(--gold); }
.blog-card .meta { font-size: 0.85rem; color: var(--gray-400); margin-bottom: 10px; line-height: 1.5; }
.blog-card .cat { display: inline-block; background: var(--gray-100); padding: 5px 12px; border-radius: 50px; font-size: 0.75rem; color: var(--gray-400); font-weight: 500; }

/* ── Used Parts Note ── */
.used-parts-note {
  text-align: center;
  color: var(--gray-400);
  font-size: 0.85rem;
  max-width: 560px;
  margin: 20px auto 0;
  line-height: 1.6;
  font-style: italic;
}

/* ── Utility ── */
.text-center { text-align: center; }
.mt-24 { margin-top: 24px; }
.mt-48 { margin-top: 48px; }

/* ── Contact Info Block ── */
.contact-info-block {
  text-align: center;
  padding: 32px 0 0;
}
.contact-info-block p { margin-bottom: 10px; font-size: 0.95rem; }
.contact-info-block strong { color: var(--navy); display: block; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 2px; }
.contact-info-block a { font-size: 1.05rem; font-weight: 600; }