:root {
    --bg: #09101a;
    --surface: #ffffff;
    --surface-alt: #eef3f8;
    --text: #17304b;
    --muted: #5d7086;
    --primary: #2ca7b8;
    --primary-dark: #1d8492;
    --accent: #f0b44c;
    --border: rgba(23, 48, 75, 0.1);
    --shadow: 0 18px 55px rgba(5, 19, 38, 0.12);
    --radius: 22px;
    --container: 1180px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: "Inter", "Noto Sans SC", sans-serif;
    color: var(--text);
    background: #fff;
    line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
main { min-height: 60vh; }
.container { width: min(var(--container), calc(100% - 2rem)); margin: 0 auto; }
.center { text-align: center; }
.narrow { max-width: 760px; margin-inline: auto; }
.site-header {
    position: sticky; top: 0; z-index: 50;
    backdrop-filter: blur(16px);
    background: rgba(7, 18, 33, 0.86);
    border-bottom: 1px solid rgba(255,255,255,0.08);
}
.nav-wrap { display: flex; align-items: center; gap: 1rem; min-height: 86px; }
.brand img { width: 240px; max-width: 45vw; border-radius: 8px; }
.main-nav { display: flex; align-items: center; gap: 1.1rem; margin-left: auto; }
.main-nav a, .lang-switch a {
    color: rgba(255,255,255,0.86);
    font-weight: 600;
    padding: .72rem 1rem;
    border-radius: 999px;
    transition: .25s ease;
}
.main-nav a:hover, .lang-switch a:hover,
.main-nav a.active, .lang-switch a.active { background: rgba(255,255,255,0.14); color: #fff; }
.lang-switch { display: flex; gap: .35rem; }
.nav-toggle { display: none; margin-left: auto; background: none; border: 0; padding: 0; cursor: pointer; }
.nav-toggle span { display: block; width: 24px; height: 2px; background: #fff; margin: 5px 0; }
.hero { position: relative; overflow: hidden; color: #fff; }
.hero-home { min-height: 82vh; display: grid; align-items: center; }
.hero-sub { min-height: 44vh; display: grid; align-items: end; }
.hero-bg { position: absolute; inset: 0; background-size: cover; background-position: center; transform: scale(1.02); }
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(135deg, rgba(7, 18, 33, 0.82), rgba(12, 47, 70, 0.45)); }
.hero-overlay.dark { background: linear-gradient(135deg, rgba(7, 18, 33, 0.86), rgba(10, 24, 48, 0.55)); }
.hero-content { position: relative; padding: 6rem 0; }
.hero-content.small { padding: 5rem 0 4rem; }
.eyebrow, .section-kicker {
    display: inline-block; margin: 0 0 1rem;
    text-transform: uppercase; letter-spacing: .18em; font-size: .78rem; font-weight: 800;
    color: var(--accent);
}
.hero h1 { margin: 0; max-width: 880px; font-size: clamp(2.4rem, 4.7vw, 5rem); line-height: 1.05; }
.rotator-line { display: flex; flex-wrap: wrap; gap: .3rem; font-size: clamp(1.05rem, 1.8vw, 1.55rem); margin: 1.4rem 0 1rem; font-weight: 700; }
.rotator-prefix { color: rgba(255,255,255,0.76); }
.rotator-word { min-width: 240px; color: #fff; position: relative; }
.hero-text { max-width: 760px; font-size: 1.08rem; color: rgba(255,255,255,0.88); }
.hero-text.narrow { max-width: 700px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: 2rem; }
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: .95rem 1.5rem; border-radius: 999px; font-weight: 700; border: 0; cursor: pointer;
    transition: transform .2s ease, background .2s ease, color .2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-secondary { background: rgba(255,255,255,0.16); color: #fff; border: 1px solid rgba(255,255,255,0.16); }
.btn-secondary:hover { background: rgba(255,255,255,0.26); }
.section { padding: 5.2rem 0; }
.section-alt { background: var(--surface-alt); }
.section-head { margin-bottom: 2.2rem; }
.section h2 { font-size: clamp(1.85rem, 3.2vw, 3rem); line-height: 1.2; margin: 0 0 1rem; }
.section p { margin-top: 0; color: var(--muted); }
.market-grid { display: flex; flex-wrap: wrap; gap: 1rem; justify-content: center; margin-top: 2rem; }
.market-chip {
    background: #fff; border: 1px solid var(--border); padding: 1rem 1.3rem; border-radius: 999px;
    min-width: 150px; font-weight: 700; box-shadow: var(--shadow);
}
.two-col { display: grid; grid-template-columns: 1.15fr .85fr; gap: 2rem; align-items: center; }
.image-card img, .panel, .feature-card, .product-card, .info-card, .product-preview {
    border-radius: var(--radius);
}
.image-card img { box-shadow: var(--shadow); width: 100%; height: 100%; object-fit: cover; min-height: 360px; }
.panel, .feature-card, .info-card, .product-card, .product-preview, .contact-form, .contact-panel {
    background: #fff; border: 1px solid var(--border); box-shadow: var(--shadow);
}
.panel { padding: 2rem; }
.feature-grid, .card-grid, .product-grid { display: grid; gap: 1.4rem; }
.feature-grid { grid-template-columns: repeat(4, 1fr); }
.card-grid.three { grid-template-columns: repeat(3, 1fr); }
.feature-card, .info-card { padding: 1.8rem; }
.feature-card h3, .info-card h3, .product-card h3 { margin-top: 0; margin-bottom: .7rem; font-size: 1.15rem; }
.product-preview-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.4rem; }
.product-preview img { width: 100%; height: 270px; object-fit: cover; border-top-left-radius: var(--radius); border-top-right-radius: var(--radius); }
.product-preview div { padding: 1.1rem 1.3rem; }
.cta-section { background: linear-gradient(135deg, #0e2740, #163d60); color: #fff; }
.cta-section h2, .cta-section p { color: rgba(255,255,255,0.92); }
.icon-list { list-style: none; padding: 0; margin: 0; }
.icon-list li { position: relative; padding-left: 1.4rem; margin-bottom: .8rem; color: var(--muted); }
.icon-list li::before { content: ''; position: absolute; left: 0; top: .55rem; width: .55rem; height: .55rem; border-radius: 50%; background: var(--primary); }
.icon-list.large li { margin-bottom: 1rem; }
.product-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.product-card { overflow: hidden; }
.product-card img { width: 100%; height: 210px; object-fit: cover; }
.product-card-body { padding: 1.35rem 1.3rem 1.6rem; }
.contact-grid { display: grid; gap: 1.6rem; grid-template-columns: .9fr 1.1fr; align-items: start; }
.contact-list p { margin-bottom: .8rem; }
.small-note { font-size: .92rem; }
.contact-form { padding: 2rem; }
.form-grid { display: grid; gap: 1rem; grid-template-columns: repeat(2, 1fr); }
.form-grid label { display: block; }
.form-grid .full { grid-column: 1 / -1; }
.form-grid span { display: block; margin-bottom: .5rem; font-weight: 600; color: var(--text); }
input, select, textarea {
    width: 100%; padding: .92rem 1rem; border-radius: 14px; border: 1px solid rgba(18,47,75,0.18);
    font: inherit; color: var(--text); background: #fff;
}
textarea { resize: vertical; }
input:focus, select:focus, textarea:focus { outline: 2px solid rgba(44,167,184,.18); border-color: var(--primary); }
.checkbox { display: flex !important; align-items: flex-start; gap: .75rem; }
.checkbox input { width: auto; margin-top: .2rem; }
.checkbox span { margin: 0; }
.hp-field { position: absolute !important; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.alert { padding: 1rem 1.1rem; border-radius: 14px; margin-bottom: 1rem; font-weight: 600; }
.alert.success { background: rgba(46, 184, 92, 0.12); color: #156b34; border: 1px solid rgba(46, 184, 92, 0.2); }
.alert.error { background: rgba(217, 60, 60, 0.1); color: #912f2f; border: 1px solid rgba(217, 60, 60, 0.2); }
.site-footer { background: #071221; color: rgba(255,255,255,0.82); padding-top: 3.5rem; }
.footer-grid { display: grid; gap: 1.6rem; grid-template-columns: 1.4fr 1fr 1fr; }
.footer-logo { width: 180px; border-radius: 8px; margin-bottom: 1rem; }
.site-footer h4 { color: #fff; margin-top: 0; margin-bottom: .75rem; }
.site-footer p, .site-footer a { color: rgba(255,255,255,0.72); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); margin-top: 2rem; padding: 1rem 0 1.5rem; font-size: .94rem; }
.reveal { opacity: 1; transform: none; transition: opacity .55s ease, transform .55s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }
@media (max-width: 1080px) {
    .feature-grid, .product-grid { grid-template-columns: repeat(2, 1fr); }
    .product-preview-grid, .card-grid.three { grid-template-columns: repeat(2, 1fr); }
    .two-col, .contact-grid, .footer-grid { grid-template-columns: 1fr; }
}
@media (max-width: 1080px) {
    .nav-toggle { display: block; }
    .main-nav {
        position: absolute; left: 1rem; right: 1rem; top: calc(100% + .6rem); display: none;
        flex-direction: column; align-items: stretch; padding: .75rem; border-radius: 20px;
        background: rgba(7, 18, 33, 0.96); box-shadow: var(--shadow);
    }
    .main-nav.open { display: flex; }
    .lang-switch { margin-left: auto; }
    .feature-grid, .product-preview-grid { grid-template-columns: 1fr; }
}
@media (max-width: 680px) {
    .hero-home { min-height: 72vh; }
    .hero-content { padding: 5rem 0; }
    .section { padding: 4rem 0; }
    .product-grid, .card-grid.three { grid-template-columns: 1fr; }
    .form-grid { grid-template-columns: 1fr; }
    .brand img { width: 200px; }
    .lang-switch { display: flex; gap: 0; margin-left: 0; }
    .lang-switch a { padding: .5rem .4rem; font-size: .82rem; }
    .brand img { width: min(160px, 40vw); }
    .nav-wrap { gap: .65rem; }
}

/* Revision 02: six distinct product families, images and accessible navigation. */
.product-card { scroll-margin-top: 105px; }
.product-card .family-photo { height: 245px; width: 100%; object-fit: cover; }
.product-preview .family-photo { width: 100%; height: 270px; object-fit: cover; }
.photo-pressure-vessels { object-position: 50% 40%; }
.photo-reactors-columns { object-position: 50% 55%; }
.photo-heat-exchangers { object-position: 65% 60%; }
.photo-skids-packages { object-position: 50% 50%; }
.photo-combustion-hot-gas { object-position: 45% 40%; }
.photo-special-equipment { object-position: 50% 70%; }
.image-disclaimer { margin: 1.4rem auto 0 !important; font-size: .84rem; text-align: center; max-width: 850px; }
.photo-credits-section { padding: 2rem 0; }
.photo-credits { border: 1px solid var(--border); border-radius: 14px; padding: 1rem 1.2rem; scroll-margin-top: 100px; }
.photo-credits summary { cursor: pointer; font-weight: 600; }
.photo-credits p, .photo-credits dd { font-size: .88rem; color: var(--muted); }
.photo-credits p:first-of-type { margin-top: 1rem; }
.photo-credits dt { margin-top: .75rem; font-weight: 600; }
.photo-credits dd { margin-left: 0; }
.photo-credits a { text-decoration: underline; text-underline-offset: .15em; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: .75rem; }
a:focus-visible, button:focus-visible, summary:focus-visible { outline: 3px solid var(--primary); outline-offset: 4px; }
.nav-toggle { min-width: 32px; min-height: 44px; }
@media (max-width: 1080px) {
    .main-nav { margin-left: 0; }
    .nav-wrap { justify-content: space-between; }
    .lang-switch { margin-left: 0; }
    .product-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
    .product-grid { grid-template-columns: 1fr; }
    .product-card .family-photo { height: 240px; }
    .panel, .contact-form { padding: 1.2rem; }
}
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { animation: none !important; transition: none !important; }
}