/* ============================================================
   Zhuohong Electric - English Corporate Website
   Modern industrial B2B design
   ============================================================ */

:root {
    --primary: #1a365d;
    --primary-light: #2b6cb0;
    --primary-dark: #0f1f3d;
    --accent: #e94560;
    --accent-hover: #c53030;
    --text: #2d3748;
    --text-light: #718096;
    --bg: #ffffff;
    --bg-alt: #f7fafc;
    --bg-dark: #1a1a2e;
    --border: #e2e8f0;
    --shadow: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
    --radius: 12px;
    --radius-sm: 6px;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--primary-light); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent); }

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

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ===== TOP BAR ===== */
.top-bar {
    background: var(--primary-dark);
    color: rgba(255,255,255,0.8);
    font-size: 13px;
    padding: 8px 0;
}
.top-bar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}
.top-bar a { color: rgba(255,255,255,0.8); }
.top-bar a:hover { color: #fff; }
.top-bar-left, .top-bar-right { display: flex; gap: 16px; align-items: center; }

/* ===== HEADER / NAV ===== */
.header {
    background: var(--primary);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.15);
}
.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    color: #fff;
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0.5px;
}
.logo span { color: var(--accent); }
.logo small {
    font-size: 11px;
    font-weight: 400;
    color: rgba(255,255,255,0.6);
    display: block;
    letter-spacing: 1px;
}

.nav { display: flex; gap: 4px; }
.nav a {
    color: rgba(255,255,255,0.85);
    padding: 8px 18px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    transition: all 0.25s;
}
.nav a:hover,
.nav a.active {
    background: rgba(255,255,255,0.15);
    color: #fff;
}

.lang-switch {
    display: flex;
    gap: 4px;
    margin-left: 16px;
}
.lang-switch a {
    font-size: 12px;
    padding: 4px 10px;
    border-radius: 4px;
    background: rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.7);
    font-weight: 400;
}
.lang-switch a.active {
    background: var(--accent);
    color: #fff;
}
.lang-switch a:hover { background: rgba(255,255,255,0.25); color: #fff; }

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 28px;
    cursor: pointer;
    padding: 8px;
}
.mobile-nav { display: none; }

/* ===== HERO ===== */
.hero {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
    color: #fff;
    padding: 100px 0 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.hero::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 60px;
    background: var(--bg);
    clip-path: ellipse(55% 100% at 50% 100%);
}
.hero h1 {
    font-size: 48px;
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}
.hero h1 span { color: var(--accent); }
.hero p {
    font-size: 18px;
    color: rgba(255,255,255,0.75);
    max-width: 700px;
    margin: 0 auto 32px;
    line-height: 1.8;
}
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
    display: inline-block;
    padding: 14px 36px;
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s;
    cursor: pointer;
    border: none;
}
.btn-primary {
    background: var(--accent);
    color: #fff;
}
.btn-primary:hover {
    background: var(--accent-hover);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(233,69,96,0.4);
}
.btn-outline {
    background: transparent;
    color: #fff;
    border: 2px solid rgba(255,255,255,0.3);
}
.btn-outline:hover {
    border-color: #fff;
    color: #fff;
    transform: translateY(-2px);
}
.btn-outline-dark {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}
.btn-outline-dark:hover {
    background: var(--primary);
    color: #fff;
    transform: translateY(-2px);
}

/* ===== SECTIONS ===== */
.section { padding: 80px 0; }
.section-alt { background: var(--bg-alt); }
.section-title {
    text-align: center;
    margin-bottom: 16px;
}
.section-title h2 {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 12px;
}
.section-title p {
    color: var(--text-light);
    font-size: 16px;
    max-width: 600px;
    margin: 0 auto;
}
.section-divider {
    width: 60px;
    height: 4px;
    background: var(--accent);
    margin: 0 auto 40px;
    border-radius: 2px;
}

/* ===== FEATURES / ABOUT INTRO ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 40px;
}
.feature-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 36px 28px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
    text-align: center;
    border: 1px solid var(--border);
}
.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}
.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 24px;
}
.feature-card h3 {
    font-size: 18px;
    margin-bottom: 8px;
    color: var(--primary);
}
.feature-card p {
    color: var(--text-light);
    font-size: 14px;
    line-height: 1.7;
}

/* ===== PRODUCT GRID ===== */
.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 40px;
}
.product-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s;
    border: 1px solid var(--border);
}
.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}
.product-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}
.product-card-body {
    padding: 20px;
}
.product-card-body h3 {
    font-size: 16px;
    margin-bottom: 6px;
    color: var(--primary);
}
.product-card-body p {
    color: var(--text-light);
    font-size: 13px;
    line-height: 1.6;
}

/* ===== COMPANY INTRO ===== */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    margin-top: 40px;
}
.about-text h3 {
    font-size: 24px;
    color: var(--primary);
    margin-bottom: 16px;
}
.about-text p {
    color: var(--text-light);
    margin-bottom: 16px;
    line-height: 1.9;
}
.about-image img {
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
}

/* ===== STATS ===== */
.stats {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    color: #fff;
    padding: 60px 0;
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    text-align: center;
}
.stat-item h3 {
    font-size: 36px;
    font-weight: 800;
    color: var(--accent);
}
.stat-item p {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    margin-top: 4px;
}

/* ===== CONTACT ===== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 40px;
}
.contact-info h3 {
    font-size: 22px;
    color: var(--primary);
    margin-bottom: 20px;
}
.contact-info-item {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
    align-items: flex-start;
}
.contact-info-icon {
    width: 40px;
    height: 40px;
    background: var(--bg-alt);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}
.contact-info-item div { flex: 1; }
.contact-info-item label {
    font-size: 12px;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 1px;
}
.contact-info-item p {
    font-weight: 500;
    color: var(--text);
}

.contact-form { background: #fff; border-radius: var(--radius); padding: 36px; box-shadow: var(--shadow); border: 1px solid var(--border); }
.contact-form h3 { font-size: 20px; color: var(--primary); margin-bottom: 20px; }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; color: var(--text); margin-bottom: 6px; }
.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-family: var(--font);
    transition: border-color 0.2s;
}
.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(43,108,176,0.1);
}
.form-group textarea { height: 120px; resize: vertical; }

/* ===== FOOTER ===== */
.footer {
    background: var(--bg-dark);
    color: rgba(255,255,255,0.7);
    padding: 60px 0 30px;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}
.footer h4 {
    color: #fff;
    font-size: 16px;
    margin-bottom: 16px;
}
.footer p { font-size: 13px; line-height: 1.8; }
.footer a { color: rgba(255,255,255,0.6); font-size: 13px; display: block; margin-bottom: 8px; }
.footer a:hover { color: var(--accent); }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 20px;
    text-align: center;
    font-size: 12px;
    color: rgba(255,255,255,0.4);
}
.footer-bottom a { display: inline; color: rgba(255,255,255,0.4); margin: 0 4px; }

/* ===== PAGE HEADER (inner pages) ===== */
.page-header {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    color: #fff;
    padding: 60px 0;
    text-align: center;
}
.page-header h1 { font-size: 36px; font-weight: 700; margin-bottom: 8px; }
.page-header p { color: rgba(255,255,255,0.7); font-size: 16px; max-width: 700px; margin: 0 auto; }

/* ===== ABOUT PAGE ===== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-top: 40px;
}
.about-text-block {
    background: #fff;
    border-radius: var(--radius);
    padding: 36px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}
.about-text-block h3 { font-size: 20px; color: var(--primary); margin-bottom: 12px; }
.about-text-block p { color: var(--text-light); line-height: 1.9; font-size: 14px; }

.values-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 40px;
}
.value-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    text-align: center;
    transition: all 0.3s;
}
.value-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.value-icon { font-size: 36px; margin-bottom: 12px; }
.value-card h4 { font-size: 18px; color: var(--primary); margin-bottom: 8px; }
.value-card p { color: var(--text-light); font-size: 13px; line-height: 1.7; }

/* ===== PRODUCTS PAGE ===== */
.product-category {
    margin-bottom: 48px;
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    overflow: hidden;
}
.product-category-header {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff;
    padding: 20px 28px;
}
.product-category-header h3 {
    font-size: 22px;
    font-weight: 700;
}
.product-category-header p {
    color: rgba(255,255,255,0.8);
    font-size: 14px;
    margin-top: 4px;
}
.product-category-body {
    padding: 28px;
}
.product-category-body p {
    color: var(--text-light);
    line-height: 1.9;
    margin-bottom: 12px;
}
.product-category-body .specs {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 8px;
    margin-top: 12px;
}
.product-category-body .specs li {
    list-style: none;
    font-size: 13px;
    color: var(--text);
    padding: 6px 12px;
    background: var(--bg-alt);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--accent);
}
.product-category-body .specs li::before { content: '\\2713 '; color: var(--accent); font-weight: bold; }

.product-showcase {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    padding: 28px;
    background: var(--bg-alt);
    border-top: 1px solid var(--border);
}
.product-showcase img {
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    transition: transform 0.3s;
    width: 100%;
    height: auto;
}
.product-showcase img:hover { transform: scale(1.02); }
.product-showcase .spec-img {
    border: 1px solid var(--border);
}
.product-showcase .spec-label {
    font-size: 12px;
    color: var(--text-light);
    text-align: center;
    margin-top: 6px;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .menu-toggle { display: block; }
    .nav { display: none; }
    .mobile-nav {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--primary);
        flex-direction: column;
        padding: 16px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.2);
        z-index: 999;
    }
    .mobile-nav.open { display: flex; }
    .mobile-nav a {
        color: rgba(255,255,255,0.85);
        padding: 12px 16px;
        border-radius: var(--radius-sm);
        font-size: 16px;
        font-weight: 500;
        border-bottom: 1px solid rgba(255,255,255,0.1);
    }
    .mobile-nav a:last-child { border-bottom: none; }
    .mobile-nav a:hover, .mobile-nav a.active { background: rgba(255,255,255,0.15); color: #fff; }
    .lang-switch { margin-left: 0; }
    .top-bar .container { flex-direction: column; gap: 4px; }

    .hero { padding: 60px 0 50px; }
    .hero h1 { font-size: 28px; }
    .hero p { font-size: 15px; }

    .features-grid,
    .product-grid { grid-template-columns: 1fr; }

    .about-content,
    .contact-grid,
    .about-grid { grid-template-columns: 1fr; gap: 30px; }

    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .values-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 24px; }

    .section-title h2 { font-size: 26px; }
    .section { padding: 50px 0; }

    .product-showcase { grid-template-columns: 1fr; }
    .page-header h1 { font-size: 28px; }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .features-grid,
    .product-grid { grid-template-columns: repeat(2, 1fr); }
    .values-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .product-showcase { grid-template-columns: 1fr; }
}