/* ==========================================================================
   Ningbo Xuteng Petrochemical Co., Ltd. — Corporate Website
   Industrial Blue Theme
   ========================================================================== */

:root {
  --navy-900: #071f33;
  --navy-800: #0b2c4d;
  --navy-700: #123d68;
  --blue-600: #155a9c;
  --blue-500: #1b6cb3;
  --blue-400: #2e86de;
  --blue-100: #dcebfa;
  --blue-50:  #eef5fc;
  --accent:   #e8971d;      /* warm amber accent for CTAs */
  --accent-dark: #c87e0f;
  --ink:      #22313f;
  --muted:    #5b6b7c;
  --line:     #e3e9f0;
  --bg:       #f5f8fc;
  --white:    #ffffff;
  --green:    #1e9e6a;

  --radius:   12px;
  --radius-sm: 8px;
  --shadow-sm: 0 2px 8px rgba(11, 44, 77, .06);
  --shadow-md: 0 10px 30px rgba(11, 44, 77, .12);
  --shadow-lg: 0 20px 50px rgba(11, 44, 77, .18);

  --font: "Segoe UI", -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  --container: 1180px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue-500); text-decoration: none; }
a:hover { color: var(--blue-400); }

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

.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 24px; }

.section { padding: 84px 0; }
.section--alt { background: var(--white); }
.section--blue { background: linear-gradient(160deg, var(--navy-800), var(--navy-700)); color: #fff; }

.section-head { text-align: center; max-width: 720px; margin: 0 auto 52px; }
.section-head .eyebrow {
  display: inline-block; text-transform: uppercase; letter-spacing: .18em;
  font-size: .78rem; font-weight: 700; color: var(--blue-500);
  margin-bottom: 14px;
}
.section-head h2 { font-size: 2.15rem; line-height: 1.2; color: var(--navy-800); margin-bottom: 16px; }
.section-head p { color: var(--muted); font-size: 1.05rem; }
.section--blue .section-head h2 { color: #fff; }
.section--blue .section-head p { color: rgba(255,255,255,.75); }
.section--blue .section-head .eyebrow { color: var(--accent); }

/* --------------------------------------------------------------------------
   Header / Navigation
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.96);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 74px; }
.brand { display: flex; align-items: center; gap: 14px; }
.brand img { height: 46px; width: 46px; object-fit: contain; border-radius: 10px; }
.brand .brand-text { line-height: 1.1; }
.brand .brand-text strong { display: block; color: var(--navy-800); font-size: 1.06rem; letter-spacing: .01em; }
.brand .brand-text span { display: block; color: var(--muted); font-size: .72rem; letter-spacing: .04em; }

.nav-links { display: flex; align-items: center; gap: 6px; list-style: none; }
.nav-links a {
  display: inline-block; padding: 9px 15px; border-radius: 8px;
  color: var(--ink); font-weight: 600; font-size: .95rem;
}
.nav-links a:hover { color: var(--blue-500); background: var(--blue-50); }
.nav-links a.active { color: var(--blue-600); background: var(--blue-50); }
.nav-cta { margin-left: 10px; }

.nav-toggle {
  display: none; width: 44px; height: 44px; border: 1px solid var(--line);
  background: #fff; border-radius: 10px; cursor: pointer;
}
.nav-toggle span { display: block; width: 20px; height: 2px; background: var(--navy-800); margin: 4px auto; transition: .25s; }

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 24px; border-radius: 999px; font-weight: 700; font-size: .95rem;
  cursor: pointer; border: 2px solid transparent; transition: .2s; line-height: 1.2;
}
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 6px 18px rgba(232,151,29,.32); }
.btn-primary:hover { background: var(--accent-dark); color: #fff; transform: translateY(-2px); }
.btn-outline { border-color: var(--blue-500); color: var(--blue-600); background: transparent; }
.btn-outline:hover { background: var(--blue-500); color: #fff; }
.btn-light { background: #fff; color: var(--navy-800); }
.btn-light:hover { background: var(--blue-50); color: var(--navy-800); transform: translateY(-2px); }
.btn-lg { padding: 15px 30px; font-size: 1.02rem; }

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(1100px 600px at 85% -10%, rgba(46,134,222,.45), transparent 60%),
    radial-gradient(800px 500px at -10% 110%, rgba(232,151,29,.25), transparent 55%),
    linear-gradient(150deg, var(--navy-900) 0%, var(--navy-700) 55%, var(--navy-800) 100%);
  color: #fff; padding: 110px 0 130px;
}
.hero::after {
  content: ""; position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size: 52px 52px; pointer-events: none;
}
.hero-inner { position: relative; z-index: 2; display: grid; grid-template-columns: 1.15fr .85fr; gap: 48px; align-items: center; }
.hero .eyebrow {
  display: inline-block; text-transform: uppercase; letter-spacing: .2em;
  font-size: .8rem; font-weight: 700; color: var(--accent); margin-bottom: 20px;
}
.hero h1 { font-size: 3.1rem; line-height: 1.08; font-weight: 800; margin-bottom: 22px; letter-spacing: -.01em; }
.hero h1 span { color: var(--accent); }
.hero p.lead { font-size: 1.18rem; color: rgba(255,255,255,.85); max-width: 560px; margin-bottom: 34px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }

.hero-stats { display: flex; flex-wrap: wrap; gap: 34px; margin-top: 46px; }
.hero-stats .stat b { display: block; font-size: 2rem; font-weight: 800; color: #fff; }
.hero-stats .stat span { color: rgba(255,255,255,.72); font-size: .92rem; }

.hero-card {
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.14);
  border-radius: 18px; padding: 30px; backdrop-filter: blur(6px);
}
.hero-card h3 { font-size: 1.05rem; margin-bottom: 18px; color: #fff; letter-spacing: .02em; }
.hero-card ul { list-style: none; }
.hero-card li {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  padding: 11px 2px; border-bottom: 1px solid rgba(255,255,255,.1); font-size: .94rem;
}
.hero-card li:last-child { border-bottom: 0; }
.hero-card li .tag { color: rgba(255,255,255,.68); }
.hero-card li .val { font-weight: 700; text-align: right; }

/* --------------------------------------------------------------------------
   Cards (general)
   -------------------------------------------------------------------------- */
.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.value-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 28px; box-shadow: var(--shadow-sm); transition: .25s;
}
.value-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: var(--blue-100); }
.value-card .icon {
  width: 56px; height: 56px; border-radius: 14px; display: grid; place-items: center;
  background: var(--blue-50); color: var(--blue-600); margin-bottom: 20px; font-size: 26px;
}
.value-card h3 { color: var(--navy-800); font-size: 1.18rem; margin-bottom: 10px; }
.value-card p { color: var(--muted); font-size: .96rem; }

/* --------------------------------------------------------------------------
   Category tiles
   -------------------------------------------------------------------------- */
.cat-tile {
  position: relative; overflow: hidden; border-radius: var(--radius);
  background: linear-gradient(160deg, var(--navy-700), var(--navy-800));
  color: #fff; padding: 30px 26px; min-height: 170px; display: flex;
  flex-direction: column; justify-content: flex-end; transition: .25s; border: 1px solid transparent;
}
.cat-tile:hover { transform: translateY(-6px); border-color: rgba(255,255,255,.2); box-shadow: var(--shadow-md); }
.cat-tile .code {
  font-family: "Consolas", "SF Mono", monospace; font-size: 1.5rem; font-weight: 700;
  color: var(--accent); margin-bottom: 6px; letter-spacing: .02em;
}
.cat-tile h3 { font-size: 1.1rem; font-weight: 700; }
.cat-tile p { color: rgba(255,255,255,.72); font-size: .86rem; margin-top: 4px; }

/* --------------------------------------------------------------------------
   Suppliers
   -------------------------------------------------------------------------- */
.supplier-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 28px; text-align: center; box-shadow: var(--shadow-sm); transition: .25s;
}
.supplier-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.supplier-logo {
  width: 86px; height: 86px; margin: 0 auto 18px; border-radius: 20px;
  display: grid; place-items: center; font-weight: 800; font-size: 1.5rem;
  color: #fff; letter-spacing: .02em;
}
.supplier-logo.s1 { background: linear-gradient(140deg, #0b4f9e, #123d68); }
.supplier-logo.s2 { background: linear-gradient(140deg, #14508c, #0b2c4d); }
.supplier-logo.s3 { background: linear-gradient(140deg, #e8971d, #c87e0f); }
.supplier-card h3 { color: var(--navy-800); font-size: 1.12rem; margin-bottom: 6px; }
.supplier-card .sub { color: var(--muted); font-size: .86rem; margin-bottom: 14px; }
.supplier-card p { color: var(--muted); font-size: .94rem; }

/* --------------------------------------------------------------------------
   Products page — filter bar
   -------------------------------------------------------------------------- */
.filter-bar {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px 24px; margin-bottom: 36px; box-shadow: var(--shadow-sm);
}
.filter-group { display: flex; align-items: center; flex-wrap: wrap; gap: 10px; }
.filter-group + .filter-group { margin-top: 14px; padding-top: 14px; border-top: 1px dashed var(--line); }
.filter-label { font-size: .8rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); min-width: 88px; }
.chip {
  padding: 8px 16px; border-radius: 999px; border: 1px solid var(--line); background: #fff;
  color: var(--ink); font-weight: 600; font-size: .88rem; cursor: pointer; transition: .18s;
}
.chip:hover { border-color: var(--blue-400); color: var(--blue-600); }
.chip.active { background: var(--blue-600); border-color: var(--blue-600); color: #fff; }

/* --------------------------------------------------------------------------
   Product cards
   -------------------------------------------------------------------------- */
.product-grid { display: grid; gap: 24px; grid-template-columns: repeat(3, 1fr); }
.product-grid .empty {
  grid-column: 1 / -1; text-align: center; padding: 60px 20px; color: var(--muted);
  background: #fff; border: 1px dashed var(--line); border-radius: var(--radius);
}
.product-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm); transition: .25s; display: flex; flex-direction: column;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.product-media { position: relative; height: 200px; background: var(--blue-50); overflow: hidden; }
.product-media img { width: 100%; height: 100%; object-fit: cover; transition: .4s; }
.product-card:hover .product-media img { transform: scale(1.06); }
.product-badge {
  position: absolute; top: 12px; left: 12px; background: var(--navy-800); color: #fff;
  font-size: .72rem; font-weight: 700; letter-spacing: .04em; padding: 5px 11px; border-radius: 999px;
}
.product-body { padding: 20px 20px 22px; display: flex; flex-direction: column; flex: 1; }
.product-body .grade { font-family: "Consolas","SF Mono",monospace; font-size: 1.28rem; font-weight: 800; color: var(--navy-800); letter-spacing: .01em; }
.product-body .name { color: var(--blue-600); font-weight: 600; font-size: .95rem; margin: 3px 0 8px; }
.product-body .desc { color: var(--muted); font-size: .9rem; flex: 1; }
.product-meta { display: flex; align-items: center; justify-content: space-between; margin-top: 16px; }
.product-meta .supplier { font-size: .8rem; color: var(--muted); font-weight: 600; }
.btn-view {
  border: 1px solid var(--blue-500); color: var(--blue-600); background: #fff;
  padding: 7px 16px; border-radius: 999px; font-size: .85rem; font-weight: 700; cursor: pointer; transition: .18s;
}
.btn-view:hover { background: var(--blue-500); color: #fff; }

/* --------------------------------------------------------------------------
   Modal (product detail)
   -------------------------------------------------------------------------- */
.modal {
  position: fixed; inset: 0; z-index: 200; display: none; align-items: flex-start;
  justify-content: center; padding: 40px 16px; overflow-y: auto;
}
.modal.open { display: flex; }
.modal-backdrop { position: fixed; inset: 0; background: rgba(7,31,51,.66); backdrop-filter: blur(3px); }
.modal-dialog {
  position: relative; background: #fff; border-radius: 18px; width: 100%; max-width: 860px;
  box-shadow: var(--shadow-lg); overflow: hidden; animation: pop .22s ease;
}
@keyframes pop { from { transform: translateY(24px); opacity: 0; } to { transform: none; opacity: 1; } }
.modal-close {
  position: absolute; top: 16px; right: 16px; z-index: 5; width: 40px; height: 40px;
  border-radius: 50%; border: none; background: rgba(255,255,255,.92); cursor: pointer;
  font-size: 20px; color: var(--navy-800); box-shadow: var(--shadow-sm);
}
.modal-hero { display: grid; grid-template-columns: 1fr 1fr; gap: 0; background: var(--blue-50); }
.modal-hero .gallery-main { height: 320px; }
.modal-hero .gallery-main img { width: 100%; height: 100%; object-fit: cover; }
.modal-hero .gallery-side { display: grid; grid-template-rows: 1fr 1fr; gap: 0; height: 320px; }
.modal-hero .gallery-side img { width: 100%; height: 100%; object-fit: cover; border-left: 2px solid #fff; }
.modal-hero .gallery-side img:first-child { border-bottom: 2px solid #fff; }
.modal-body { padding: 28px 30px 34px; }
.modal-body h3 { font-size: 1.7rem; color: var(--navy-800); margin-bottom: 4px; }
.modal-body .subtitle { color: var(--blue-600); font-weight: 600; margin-bottom: 18px; }
.modal-section { margin-top: 22px; }
.modal-section h4 {
  font-size: .82rem; text-transform: uppercase; letter-spacing: .1em; color: var(--blue-600);
  margin-bottom: 12px; padding-bottom: 8px; border-bottom: 2px solid var(--blue-100);
}
.spec-table { width: 100%; border-collapse: collapse; font-size: .92rem; }
.spec-table th, .spec-table td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--line); }
.spec-table th { background: var(--blue-50); color: var(--navy-800); font-weight: 700; }
.spec-table tr:last-child td { border-bottom: 0; }
.app-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.app-tags span { background: var(--blue-50); color: var(--blue-600); font-size: .85rem; font-weight: 600; padding: 6px 14px; border-radius: 999px; }

/* --------------------------------------------------------------------------
   About page
   -------------------------------------------------------------------------- */
.about-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; }
.about-copy h2 { font-size: 2rem; color: var(--navy-800); margin-bottom: 18px; }
.about-copy p { color: var(--muted); margin-bottom: 16px; }
.about-figure {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px; box-shadow: var(--shadow-md); text-align: center;
}
.about-figure img { border-radius: var(--radius-sm); margin-bottom: 16px; }
.about-figure figcaption { color: var(--muted); font-size: .9rem; }

.timeline { list-style: none; position: relative; padding-left: 28px; }
.timeline::before { content: ""; position: absolute; left: 8px; top: 6px; bottom: 6px; width: 2px; background: var(--blue-100); }
.timeline li { position: relative; margin-bottom: 26px; }
.timeline li::before {
  content: ""; position: absolute; left: -26px; top: 6px; width: 14px; height: 14px;
  border-radius: 50%; background: var(--blue-500); box-shadow: 0 0 0 4px var(--blue-100);
}
.timeline b { color: var(--navy-800); display: block; font-size: 1.05rem; }
.timeline span { color: var(--muted); font-size: .92rem; }

/* --------------------------------------------------------------------------
   Contact page
   -------------------------------------------------------------------------- */
.contact-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 32px; align-items: start; }
.contact-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow-sm);
}
.contact-item { display: flex; gap: 16px; padding: 16px 0; border-bottom: 1px solid var(--line); }
.contact-item:last-child { border-bottom: 0; }
.contact-item .icon {
  flex: 0 0 auto; width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center;
  background: var(--blue-50); color: var(--blue-600); font-size: 20px;
}
.contact-item b { display: block; color: var(--navy-800); font-size: .92rem; }
.contact-item a, .contact-item p { color: var(--muted); font-size: .95rem; word-break: break-word; }
.contact-item a:hover { color: var(--blue-500); }

.form-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow-sm); }
.form-card h3 { color: var(--navy-800); margin-bottom: 6px; }
.form-card .hint { color: var(--muted); font-size: .9rem; margin-bottom: 22px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: .86rem; font-weight: 700; color: var(--navy-800); margin-bottom: 7px; }
.field input, .field textarea, .field select {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--radius-sm);
  font-family: inherit; font-size: .96rem; color: var(--ink); background: #fbfcfe; transition: .18s;
}
.field input:focus, .field textarea:focus, .field select:focus {
  outline: none; border-color: var(--blue-400); background: #fff; box-shadow: 0 0 0 3px var(--blue-100);
}
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

.map-embed { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); height: 100%; min-height: 320px; background: var(--blue-50); }

/* --------------------------------------------------------------------------
   CTA band
   -------------------------------------------------------------------------- */
.cta-band {
  background: linear-gradient(140deg, var(--blue-600), var(--navy-700));
  border-radius: 20px; padding: 48px 52px; color: #fff; display: flex;
  align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap;
  box-shadow: var(--shadow-lg);
}
.cta-band h2 { font-size: 1.8rem; margin-bottom: 8px; }
.cta-band p { color: rgba(255,255,255,.82); }

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer { background: var(--navy-900); color: rgba(255,255,255,.72); padding: 60px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1.2fr; gap: 36px; padding-bottom: 44px; }
.site-footer h4 { color: #fff; font-size: .95rem; margin-bottom: 18px; }
.site-footer ul { list-style: none; }
.site-footer ul li { margin-bottom: 10px; }
.site-footer ul a { color: rgba(255,255,255,.66); font-size: .92rem; }
.site-footer ul a:hover { color: var(--accent); }
.footer-brand img { height: 46px; width: 46px; object-fit: contain; border-radius: 10px; margin-bottom: 14px; background: #fff; }
.footer-brand p { font-size: .92rem; margin-top: 14px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1); padding: 22px 0; font-size: .85rem;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
}
.footer-bottom a { color: rgba(255,255,255,.66); }

/* --------------------------------------------------------------------------
   Utilities / reveal animation
   -------------------------------------------------------------------------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
.emoji { font-size: 1.4em; }

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 960px) {
  .grid-3, .grid-4, .product-grid { grid-template-columns: repeat(2, 1fr); }
  .grid-2, .hero-inner, .about-grid, .contact-grid { grid-template-columns: 1fr; }
  .hero { padding: 70px 0 90px; }
  .hero h1 { font-size: 2.4rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .modal-hero { grid-template-columns: 1fr; }
  .modal-hero .gallery-side { grid-template-columns: 1fr 1fr; grid-template-rows: none; height: 180px; }
  .modal-hero .gallery-side img { border-left: 0; border-top: 2px solid #fff; }
  .modal-hero .gallery-side img:first-child { border-bottom: 0; }
}

@media (max-width: 640px) {
  .grid-3, .grid-4, .product-grid, .grid-2, .footer-grid { grid-template-columns: 1fr; }
  .section { padding: 60px 0; }
  .section-head h2 { font-size: 1.7rem; }
  .hero h1 { font-size: 2rem; }
  .hero-stats { gap: 22px; }
  .field-row { grid-template-columns: 1fr; }
  .cta-band { padding: 34px 26px; }
  .nav-links {
    position: absolute; top: 74px; left: 0; right: 0; flex-direction: column; align-items: stretch;
    background: #fff; border-bottom: 1px solid var(--line); padding: 14px 20px 20px; gap: 4px;
    display: none; box-shadow: var(--shadow-md);
  }
  .nav-links.open { display: flex; }
  .nav-cta { margin: 10px 0 0; }
  .nav-toggle { display: block; }
}