/* ===== CSS Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #fafbfc;
}

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

a {
    text-decoration: none;
    color: inherit;
}

ul, ol {
    list-style: none;
}

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

/* ===== Header ===== */
.header {
    background: #fff;
    border-bottom: 1px solid #e8eaed;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    font-size: 22px;
    font-weight: 700;
    color: #1a73e8;
    letter-spacing: -0.5px;
}

.logo span {
    color: #333;
}

.nav {
    display: flex;
    gap: 36px;
}

.nav a {
    font-size: 15px;
    font-weight: 500;
    color: #5f6368;
    transition: color 0.2s;
    position: relative;
}

.nav a:hover,
.nav a.active {
    color: #1a73e8;
}

.nav a.active::after {
    content: "";
    position: absolute;
    bottom: -24px;
    left: 0;
    width: 100%;
    height: 2px;
    background: #1a73e8;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background: #333;
    margin: 5px 0;
    transition: 0.3s;
}

/* ===== Hero Section ===== */
.hero {
    background: linear-gradient(135deg, #1a73e8 0%, #4285f4 100%);
    color: #fff;
    padding: 100px 0 120px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: 50%;
}

.hero .container {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero h1 {
    font-size: 42px;
    line-height: 1.2;
    font-weight: 700;
    margin-bottom: 20px;
}

.hero p {
    font-size: 18px;
    opacity: 0.92;
    margin-bottom: 32px;
    max-width: 520px;
}

.hero-btns {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 13px 28px;
    border-radius: 6px;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: #fff;
    color: #1a73e8;
}

.btn-primary:hover {
    background: #f1f3f4;
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 2px solid rgba(255, 255, 255, 0.6);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: #fff;
}

.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-card {
    background: rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 40px;
    width: 100%;
    max-width: 420px;
    text-align: center;
}

.hero-icon {
    width: 80px;
    height: 80px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    margin: 0 auto 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-icon svg {
    width: 40px;
    height: 40px;
    fill: #fff;
}

.hero-card h3 {
    font-size: 24px;
    margin-bottom: 12px;
}

.hero-card p {
    font-size: 15px;
    margin: 0;
    opacity: 0.85;
}

/* ===== Section Common ===== */
.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 56px;
}

.section-title h2 {
    font-size: 32px;
    font-weight: 700;
    color: #202124;
    margin-bottom: 12px;
}

.section-title p {
    font-size: 16px;
    color: #5f6368;
    max-width: 600px;
    margin: 0 auto;
}

.section-alt {
    background: #fff;
}

/* ===== Stats ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: -60px;
    position: relative;
    z-index: 2;
}

.stat-card {
    background: #fff;
    border-radius: 12px;
    padding: 28px;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    border: 1px solid #e8eaed;
}

.stat-card h3 {
    font-size: 34px;
    font-weight: 700;
    color: #1a73e8;
    margin-bottom: 6px;
}

.stat-card p {
    font-size: 14px;
    color: #5f6368;
}

/* ===== Products Grid ===== */
.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.product-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.05);
    border: 1px solid #e8eaed;
    transition: transform 0.2s, box-shadow 0.2s;
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

.product-img {
    height: 180px;
    background: linear-gradient(135deg, #e8f0fe 0%, #d2e3fc 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.product-info {
    padding: 20px;
}

.product-info h3 {
    font-size: 17px;
    font-weight: 600;
    color: #202124;
    margin-bottom: 8px;
}

.product-info p {
    font-size: 14px;
    color: #5f6368;
    line-height: 1.5;
}

/* ===== Features ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-item {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    border: 1px solid #e8eaed;
    transition: box-shadow 0.2s;
}

.feature-item:hover {
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.feature-icon {
    width: 52px;
    height: 52px;
    background: #e8f0fe;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 26px;
    height: 26px;
    fill: #1a73e8;
}

.feature-item h3 {
    font-size: 18px;
    font-weight: 600;
    color: #202124;
    margin-bottom: 10px;
}

.feature-item p {
    font-size: 14px;
    color: #5f6368;
    line-height: 1.6;
}

/* ===== About Section ===== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-content h2 {
    font-size: 32px;
    font-weight: 700;
    color: #202124;
    margin-bottom: 20px;
}

.about-content p {
    font-size: 16px;
    color: #5f6368;
    margin-bottom: 16px;
    line-height: 1.7;
}

.about-list {
    margin-top: 24px;
}

.about-list li {
    padding: 10px 0;
    font-size: 15px;
    color: #333;
    border-bottom: 1px solid #e8eaed;
    display: flex;
    align-items: center;
}

.about-list li::before {
    content: "";
    width: 6px;
    height: 6px;
    background: #1a73e8;
    border-radius: 50%;
    margin-right: 12px;
}

.about-visual {
    background: linear-gradient(135deg, #e8f0fe 0%, #d2e3fc 100%);
    border-radius: 16px;
    padding: 60px 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 360px;
}

.about-visual img {
    width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

/* ===== CTA ===== */
.cta {
    background: #1a73e8;
    color: #fff;
    padding: 80px 0;
    text-align: center;
}

.cta h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta p {
    font-size: 17px;
    opacity: 0.9;
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ===== Footer ===== */
.footer {
    background: #202124;
    color: #bdc1c6;
    padding: 60px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-brand h3 {
    font-size: 20px;
    color: #fff;
    margin-bottom: 16px;
}

.footer-brand p {
    font-size: 14px;
    line-height: 1.7;
}

.footer-col h4 {
    font-size: 15px;
    color: #fff;
    font-weight: 600;
    margin-bottom: 18px;
}

.footer-col ul li {
    margin-bottom: 10px;
}

.footer-col ul li a {
    font-size: 14px;
    color: #bdc1c6;
    transition: color 0.2s;
}

.footer-col ul li a:hover {
    color: #fff;
}

.footer-bottom {
    border-top: 1px solid #3c4043;
    padding-top: 24px;
    text-align: center;
    font-size: 13px;
    color: #9aa0a6;
}

/* ===== Page Header ===== */
.page-header {
    background: linear-gradient(135deg, #1a73e8 0%, #4285f4 100%);
    color: #fff;
    padding: 70px 0 80px;
    text-align: center;
}

.page-header h1 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 12px;
}

.page-header p {
    font-size: 16px;
    opacity: 0.9;
}

/* ===== Product Page ===== */
.product-detail-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    margin-bottom: 60px;
}

.product-gallery {
    background: #fff;
    border-radius: 12px;
    border: 1px solid #e8eaed;
    overflow: hidden;
}

.product-main-img {
    height: 360px;
    background: linear-gradient(135deg, #e8f0fe 0%, #d2e3fc 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-main-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.product-specs h2 {
    font-size: 28px;
    font-weight: 700;
    color: #202124;
    margin-bottom: 16px;
}

.product-specs p {
    font-size: 15px;
    color: #5f6368;
    margin-bottom: 20px;
    line-height: 1.7;
}

.spec-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 28px;
}

.spec-table th,
.spec-table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid #e8eaed;
    font-size: 14px;
}

.spec-table th {
    background: #f8f9fa;
    color: #5f6368;
    font-weight: 600;
    width: 140px;
}

/* ===== Contact Page ===== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.contact-info h2 {
    font-size: 28px;
    font-weight: 700;
    color: #202124;
    margin-bottom: 20px;
}

.contact-info p {
    font-size: 15px;
    color: #5f6368;
    margin-bottom: 28px;
    line-height: 1.7;
}

.contact-list li {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 24px;
}

.contact-icon {
    width: 44px;
    height: 44px;
    background: #e8f0fe;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-icon svg {
    width: 22px;
    height: 22px;
    fill: #1a73e8;
}

.contact-text h4 {
    font-size: 15px;
    font-weight: 600;
    color: #202124;
    margin-bottom: 4px;
}

.contact-text p {
    font-size: 14px;
    color: #5f6368;
    margin: 0;
}

.contact-form {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    border: 1px solid #e8eaed;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: #202124;
    margin-bottom: 6px;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid #dadce0;
    border-radius: 6px;
    font-size: 14px;
    color: #333;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: #1a73e8;
}

.form-group textarea {
    min-height: 120px;
    resize: vertical;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

/* ===== Certificates Gallery ===== */
.cert-gallery {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-top: 32px;
}

.cert-item {
    background: #fff;
    border: 1px solid #e8eaed;
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    transition: box-shadow 0.2s;
}

.cert-item:hover {
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.cert-item img {
    width: 100%;
    max-height: 320px;
    object-fit: contain;
    border-radius: 8px;
    margin-bottom: 12px;
}

.cert-item h4 {
    font-size: 16px;
    color: #202124;
    font-weight: 600;
    margin: 0;
}

/* ===== Mobile Responsive ===== */
@media (max-width: 992px) {
    .hero .container,
    .about-grid,
    .product-detail-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }

    .products-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 20px 24px;
        gap: 16px;
        border-bottom: 1px solid #e8eaed;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
    }

    .nav.active {
        display: flex;
    }

    .nav a.active::after {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }

    .hero {
        padding: 70px 0 90px;
    }

    .hero h1 {
        font-size: 30px;
    }

    .hero p {
        font-size: 16px;
    }

    .section-title h2,
    .about-content h2,
    .cta h2,
    .page-header h1 {
        font-size: 26px;
    }

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

    .footer-grid {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }
}