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

:root {
    --primary: #c41e3a;
    --primary-dark: #a0182e;
    --text: #333;
    --text-light: #666;
    --bg: #fff;
    --bg-light: #f8f8f8;
    --border: #eee;
}

body {
    font-family: -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 100;
}

nav {
    max-width: 1100px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 22px;
    font-weight: 700;
    color: var(--primary);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text);
    font-size: 15px;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary);
}

.menu-toggle {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

/* Hero */
.hero {
    margin-top: 60px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: #fff;
    text-align: center;
    padding: 120px 20px 80px;
}

.hero h1 {
    font-size: 48px;
    margin-bottom: 20px;
}

.hero p {
    font-size: 20px;
    opacity: 0.9;
    margin-bottom: 40px;
}

.btn {
    display: inline-block;
    background: #fff;
    color: var(--primary);
    padding: 14px 40px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: transform 0.3s;
}

.btn:hover {
    transform: scale(1.05);
}

/* Sections */
.section {
    padding: 80px 0;
}

.bg-light {
    background: var(--bg-light);
}

.section-title {
    font-size: 32px;
    text-align: center;
    margin-bottom: 16px;
    color: var(--text);
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    margin-bottom: 50px;
    font-size: 16px;
}

/* Certifications */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
    max-width: 700px;
    margin: 0 auto;
}

.cert-card {
    background: #fff;
    padding: 35px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 2px 15px rgba(0,0,0,0.06);
}

.cert-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--text);
}

.cert-card p {
    font-size: 14px;
    color: var(--text-light);
    margin-bottom: 15px;
}

.btn-small {
    display: inline-block;
    background: var(--primary);
    color: #fff;
    padding: 10px 20px;
    border-radius: 20px;
    text-decoration: none;
    font-size: 14px;
    transition: opacity 0.3s;
}

.btn-small:hover {
    opacity: 0.85;
}

.cert-img {
    width: 100%;
    max-width: 300px;
    border-radius: 8px;
    border: 1px solid var(--border);
    transition: transform 0.3s;
    cursor: pointer;
}

.cert-img:hover {
    transform: scale(1.03);
}

@media (max-width: 600px) {
    .cert-grid {
        grid-template-columns: 1fr;
    }
}

/* About */
.about-content {
    display: flex;
    align-items: center;
    gap: 50px;
}

.about-text {
    flex: 1;
}

.about-text p {
    margin-bottom: 16px;
    font-size: 16px;
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.stat {
    text-align: center;
    padding: 30px 20px;
    background: var(--bg-light);
    border-radius: 12px;
}

.stat-number {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: var(--primary);
}

.stat-label {
    display: block;
    font-size: 14px;
    color: var(--text-light);
    margin-top: 5px;
}

/* Products */
.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.product-card {
    background: #fff;
    padding: 35px 20px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 2px 15px rgba(0,0,0,0.06);
    transition: transform 0.3s;
}

.product-card:hover {
    transform: translateY(-5px);
}

.product-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

.product-card h3 {
    font-size: 18px;
    margin-bottom: 8px;
}

.price {
    color: var(--primary);
    font-weight: 600;
    font-size: 18px;
    margin-bottom: 10px;
}

.product-card p {
    font-size: 14px;
    color: var(--text-light);
}

/* Cases */
.cases-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.case-card {
    text-align: center;
    padding: 40px 20px;
    background: var(--bg-light);
    border-radius: 12px;
}

.case-logo {
    font-size: 48px;
    margin-bottom: 15px;
}

.case-card h3 {
    font-size: 18px;
    margin-bottom: 5px;
}

.case-card p {
    font-size: 14px;
    color: var(--text-light);
}

.case-desc {
    font-size: 13px !important;
    color: var(--text-light) !important;
    margin-top: 8px;
}

/* FAQ */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    padding: 25px;
    border-radius: 12px;
    margin-bottom: 15px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.04);
}

.faq-item h3 {
    font-size: 16px;
    color: var(--primary);
    margin-bottom: 8px;
}

.faq-item p {
    font-size: 15px;
    color: var(--text-light);
    line-height: 1.7;
}

/* Footer keywords */
.footer-keywords {
    margin-top: 8px;
    opacity: 0.6;
    font-size: 12px;
}

/* Advantages */
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.advantage {
    text-align: center;
    padding: 40px 20px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.06);
}

.adv-icon {
    font-size: 40px;
    margin-bottom: 15px;
}

.advantage h3 {
    font-size: 18px;
    margin-bottom: 10px;
}

.advantage p {
    font-size: 14px;
    color: var(--text-light);
}

/* Contact */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-info p {
    margin-bottom: 12px;
    font-size: 16px;
}

.contact-info a {
    color: var(--primary);
    text-decoration: none;
}

.contact-note {
    margin-top: 30px;
    padding: 25px;
    background: var(--bg-light);
    border-radius: 12px;
    font-size: 15px;
}

/* Footer */
footer {
    background: var(--text);
    color: #fff;
    text-align: center;
    padding: 25px 0;
    font-size: 14px;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background: #fff;
        padding: 20px;
        box-shadow: 0 5px 10px rgba(0,0,0,0.1);
    }

    .nav-links.active {
        display: flex;
    }

    .menu-toggle {
        display: block;
    }

    .hero h1 {
        font-size: 32px;
    }

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

    .about-content {
        flex-direction: column;
    }

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

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

@media (max-width: 480px) {
    .products-grid,
    .cases-grid,
    .advantages-grid {
        grid-template-columns: 1fr;
    }
}