:root {
    --primary-color: #004d99; /* Deep blue typical of tech/supply chain */
    --secondary-color: #0088cc;
    --accent-color: #ff6b00;
    --text-dark: #333333;
    --text-light: #666666;
    --bg-light: #f5f7fa;
    --white: #ffffff;
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

body {
    color: var(--text-dark);
    line-height: 1.6;
    background-color: var(--white);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header & Navigation */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
    text-decoration: none;
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.2rem;
}

.logo img {
    height: 40px;
}

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

.menu-toggle {
    display: none;
    border: none;
    background: transparent;
    color: var(--primary-color);
    font-size: 1.6rem;
    line-height: 1;
    cursor: pointer;
    padding: 4px 8px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    padding-bottom: 5px;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

/* Main Content Wrapper */
main {
    flex: 1;
}

/* Sections General */
section {
    padding: 100px 20px;
}

section:nth-child(even) {
    background-color: var(--bg-light);
}

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

.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.section-title p {
    color: var(--secondary-color);
    font-size: 1.2rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

        /* Hero Section (Index Page) */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: url('重庆富盛达供应链科技有限公司介绍PPT.PicsFolder/JPG9.jpeg') center/cover;
    color: var(--text-dark);
    text-align: center;
    padding-top: 80px;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero .hero-logo {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 30px;
}

.hero .hero-logo img {
    height: 80px;
    margin-bottom: 10px;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    color: var(--primary-color);
    letter-spacing: 2px;
}

.hero p {
    font-size: 1.5rem;
    margin-bottom: 40px;
    color: var(--text-dark);
    letter-spacing: 1px;
}

/* Page Header (Inner Pages) */
.page-header {
    height: 350px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(0,77,153,0.9) 0%, rgba(0,136,204,0.8) 100%), url('重庆富盛达供应链科技有限公司介绍PPT.PicsFolder/JPG9.jpeg') center/cover;
    color: var(--white);
    text-align: center;
    padding-top: 80px;
}

.page-header h1 {
    font-size: 3rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.btn {
    display: inline-block;
    padding: 15px 40px;
    background-color: var(--accent-color);
    color: var(--white);
    text-decoration: none;
    border-radius: 30px;
    font-size: 1.1rem;
    font-weight: bold;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(255, 107, 0, 0.4);
}

.btn:hover {
    background-color: #e65c00;
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(255, 107, 0, 0.6);
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 20px;
}

.core-concepts {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-top: 30px;
}

.concept-card {
    background: var(--white);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    border-left: 4px solid var(--primary-color);
}

.concept-card h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.about-image img {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Core Business */
.business-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.business-card {
    background: var(--white);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    transition: var(--transition);
}

.business-card:hover {
    transform: translateY(-10px);
}

.business-img {
    height: 400px;
    width: 100%;
    object-fit: cover;
}

.business-content {
    padding: 30px;
}

.business-content h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.stats-row {
    display: flex;
    justify-content: space-around;
    margin-top: 50px;
    background: var(--primary-color);
    color: var(--white);
    padding: 40px 20px;
    border-radius: 15px;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: bold;
    color: var(--accent-color);
    margin-bottom: 10px;
}

/* Digital Platform */
.digital-platform {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 50px;
    align-items: center;
}

.app-preview {
    position: relative;
    text-align: center;
}

.app-preview img {
    max-width: 50%;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.features-list {
    list-style: none;
}

.feature-item {
    display: flex;
    margin-bottom: 30px;
    background: var(--white);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: rgba(0, 136, 204, 0.1);
    color: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-right: 20px;
    flex-shrink: 0;
}

.feature-text h4 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

/* Industrial Chain */
.chain-timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.chain-timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--primary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
    border-radius: 2px;
}

.timeline-item {
    padding: 20px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
}

.timeline-item::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: var(--white);
    border: 4px solid var(--accent-color);
    top: 30px;
    border-radius: 50%;
    z-index: 1;
}

.left {
    left: 0;
}

.right {
    left: 50%;
}

.right::after {
    left: -10px;
}

.timeline-content {
    padding: 20px;
    background-color: var(--white);
    position: relative;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}

/* Map Section */
.map-section {
    text-align: center;
    margin-top: 50px;
}

.map-section img {
    max-width: 80%;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Footer */
footer {
    background-color: #1a1a1a;
    color: var(--white);
    padding: 60px 20px 20px;
    margin-top: auto;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo img {
    height: 50px;
    margin-bottom: 20px;
}

.footer-links h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--secondary-color);
}

.footer-links ul {
    list-style: none;
}

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

.footer-links a {
    color: #cccccc;
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--white);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #333;
    color: #888;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-container {
        padding: 10px 14px;
        position: relative;
        align-items: center;
        flex-wrap: wrap;
    }

    .logo img {
        height: 34px;
    }

    .logo {
        font-size: 1rem;
    }

    .menu-toggle {
        display: block;
        margin-left: auto;
    }

    .nav-links {
        display: none;
        width: 100%;
        margin-top: 10px;
        padding: 12px 0 2px;
        border-top: 1px solid #e6e6e6;
        flex-direction: column;
        gap: 10px;
    }

    header.nav-open .nav-links {
        display: flex;
    }

    .nav-links a {
        font-size: 0.9rem;
        padding: 6px 0;
        border-bottom: none !important;
    }

    /* 统一手机端留白与排版 */
    section {
        padding: 80px 15px;
    }

    .hero {
        height: auto;
        min-height: 75vh;
        padding-top: 90px;
    }

    .about-grid, .business-grid, .digital-platform {
        grid-template-columns: 1fr;
    }

    .stats-row {
        flex-direction: column;
        gap: 30px;
    }

    .chain-timeline::after {
        left: 31px;
    }

    .timeline-item {
        width: 100%;
        padding-left: 70px;
        padding-right: 25px;
    }
    .timeline-item::after {
        left: 21px;
    }
    .right {
        left: 0;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .page-header {
        height: 260px;
        padding-top: 55px;
    }

    .page-header h1 {
        font-size: 2rem;
    }

    .business-img {
        height: 260px;
    }

    .app-preview img {
        max-width: 90%;
    }

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

    /* 覆盖页面内联写死的 3/2 列网格（内联 style 通常不会被上面的 class 规则影响） */
    [style*="grid-template-columns: repeat(3, 1fr)"] {
        grid-template-columns: 1fr !important;
        gap: 20px !important;
    }

    [style*="grid-template-columns: 1fr 1fr"] {
        grid-template-columns: 1fr !important;
        gap: 20px !important;
    }

    [style*="grid-template-columns: repeat(2, 1fr)"] {
        grid-template-columns: 1fr !important;
        gap: 20px !important;
    }
}