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

body {
    font-family: 'Inter', sans-serif;
    background-color: #ffffff;
    color: #0f172a;
    line-height: 1.5;
    scroll-behavior: smooth;
}

:root {
    --primary-blue: #0a66c2;
    --primary-dark: #054a8c;
    --primary-light: #eef4fc;
    --accent-blue: #2c7be5;
    --gray-light: #f8fafc;
    --gray-border: #e2e8f0;
    --text-muted: #475569;
    --shadow-sm: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.02);
    --shadow-md: 0 20px 25px -12px rgba(0, 0, 0, 0.08);
    --transition: all 0.25s ease;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}


/* Hero 区域 */
.hero {
    background: linear-gradient(105deg, #f0f7ff 0%, #ffffff 100%);
    padding: 6rem 0 4rem;
}
.hero-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}
.hero-badge {
    background: rgba(10,102,194,0.1);
    display: inline-block;
    padding: 0.25rem 1rem;
    border-radius: 30px;
    color: var(--primary-blue);
    font-weight: 600;
    font-size: 0.8rem;
    margin-bottom: 1rem;
}
.hero-content h1 {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: #0b2b42;
}
.hero-content p {
    font-size: 1rem;
    color: var(--text-muted);
}

/* 案例筛选 */
.case-filter {
    text-align: center;
    margin: 2rem 0 3rem;
}
.filter-btn {
    background: transparent;
    border: 1px solid var(--gray-border);
    padding: 0.5rem 1.2rem;
    border-radius: 40px;
    margin: 0 0.5rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}
.filter-btn.active, .filter-btn:hover {
    background: var(--primary-blue);
    color: white;
    border-color: var(--primary-blue);
}

/* 案例网格 */
.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}
.case-card {
    background: white;
    border-radius: 28px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--gray-border);
}
.case-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}
.case-img {
    height: 220px;
    background-color: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: var(--primary-blue);
}
.case-content {
    padding: 1.5rem;
}
.case-tag {
    display: inline-block;
    background: var(--primary-light);
    color: var(--primary-blue);
    border-radius: 30px;
    padding: 0.2rem 0.8rem;
    font-size: 0.7rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}
.case-content h3 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
}
.case-location {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 1rem;
}
.case-desc {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    line-height: 1.4;
}
.case-products {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 0.8rem;
}
.product-badge {
    background: #eef2ff;
    font-size: 0.7rem;
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    color: var(--primary-dark);
}

/* 优势区域 */
.advantages-section {
    background: var(--gray-light);
    padding: 5rem 0;
}
.section-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}
.section-sub {
    text-align: center;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 3rem auto;
}
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}
.adv-card {
    background: white;
    border-radius: 24px;
    padding: 1.8rem;
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--gray-border);
}
.adv-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-sm);
}
.adv-card i {
    font-size: 2.2rem;
    color: var(--primary-blue);
    margin-bottom: 1rem;
}
.adv-card h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}
.adv-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
}


/* 响应式 */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 0.8rem;
    }
    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
    }
    .hero-content h1 {
        font-size: 2rem;
    }
    .cases-grid {
        grid-template-columns: 1fr;
    }
    .section-title {
        font-size: 1.8rem;
    }
}