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

body {
    background-color: #f8f9fa;
    color: #333;
    line-height: 1.6;
    background: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
header {
    background-color: #1a5f7a;
    color: white;
    padding: 20px 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

    .logo i {
        font-size: 2.5rem;
        color: #57cc99;
    }

.logo-text h1 {
    font-size: 1.8rem;
    margin-bottom: 5px;
}

.logo-text p {
    font-size: 0.9rem;
    opacity: 0.9;
}

.nav-menu {
    display: flex;
    gap: 25px;
    list-style: none;
}

    .nav-menu a {
        color: white;
        text-decoration: none;
        font-weight: 500;
        padding: 8px 0;
        position: relative;
        transition: color 0.3s;
    }

        .nav-menu a:hover, .nav-menu a.active {
            color: #57cc99;
        }

            .nav-menu a.active::after {
                content: '';
                position: absolute;
                bottom: 0;
                left: 0;
                width: 100%;
                height: 3px;
                background-color: #57cc99;
                border-radius: 2px;
            }

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}


/* 新增：页面顶部横幅 */
.hero-banner {
    background: linear-gradient(rgba(26, 95, 122, 0.9), rgba(26, 95, 122, 0.95)), url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" preserveAspectRatio="none"><path d="M0,0 L100,0 L100,100 Z" fill="%231a5f7a"/></svg>');
    background-size: cover;
    color: white;
    padding: 80px 0;
    text-align: center;
    margin-bottom: 50px;
    border-radius: 0 0 20px 20px;
    position: relative;
    overflow: hidden;
}

    .hero-banner::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        height: 5px;
        background: linear-gradient(to right, #57cc99, #38b2ac);
    }

.hero-title {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.hero-subtitle {
    font-size: 1.3rem;
    max-width: 800px;
    margin: 0 auto 30px;
    opacity: 0.95;
    line-height: 1.8;
}
        

/* 主要内容区 */
.main-content {
    padding: 40px 0;
    min-height: calc(100vh - 300px);
}

/* 导航卡片 */
.nav-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.nav-card {
    background: white;
    border-radius: 15px;
    padding: 35px 30px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    border: 1px solid rgba(87, 204, 153, 0.1);
    position: relative;
    overflow: hidden;
}

    .nav-card::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 5px;
        background: linear-gradient(to right, #57cc99, #38b2ac);
    }

    .nav-card:hover {
        transform: translateY(-10px);
        box-shadow: 0 15px 40px rgba(87, 204, 153, 0.15);
    }

    .nav-card i {
        font-size: 3.5rem;
        color: #1a5f7a;
        margin-bottom: 25px;
        display: block;
    }

    .nav-card h3 {
        font-size: 1.5rem;
        color: #1a5f7a;
        margin-bottom: 15px;
    }

    .nav-card p {
        color: #666;
        margin-bottom: 25px;
        line-height: 1.7;
    }

.card-btn {
    display: inline-block;
    background: linear-gradient(to right, #57cc99, #38b2ac);
    color: white;
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

    .card-btn:hover {
        transform: scale(1.05);
        box-shadow: 0 5px 15px rgba(87, 204, 153, 0.4);
    }

/* 步骤指南 */
.step-guide {
    background: white;
    border-radius: 15px;
    padding: 50px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    margin-bottom: 60px;
}

.section-title {
    text-align: center;
    color: #1a5f7a;
    margin-bottom: 50px;
    font-size: 2.2rem;
    position: relative;
}

    .section-title::after {
        content: "";
        display: block;
        width: 80px;
        height: 4px;
        background: linear-gradient(to right, #57cc99, #38b2ac);
        margin: 15px auto 0;
        border-radius: 2px;
    }

.steps-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.step-item {
    position: relative;
    padding-left: 70px;
}

.step-number {
    position: absolute;
    left: 0;
    top: 0;
    width: 50px;
    height: 50px;
    background: linear-gradient(to right, #57cc99, #38b2ac);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
    box-shadow: 0 5px 15px rgba(87, 204, 153, 0.3);
}

.step-item h3 {
    color: #1a5f7a;
    margin-bottom: 15px;
    font-size: 1.4rem;
}

.step-item p {
    color: #666;
    line-height: 1.8;
}

/* 数据可视化示例 */
.visual-demo {
    background: linear-gradient(135deg, #f0f9f5 0%, #e6f3ff 100%);
    border-radius: 15px;
    padding: 50px;
    margin-bottom: 60px;
    border: 1px solid rgba(87, 204, 153, 0.2);
}

.demo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.demo-item {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 40px 0 20px;
    margin-top: 80px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 30px;
}

.footer-section h3 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    color: #57cc99;
}

.footer-section p, .footer-section a {
    color: #bdc3c7;
    margin-bottom: 10px;
    display: block;
    text-decoration: none;
}

    .footer-section a:hover {
        color: #57cc99;
    }

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #95a5a6;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
        padding: 0 20px;
    }

    .step-guide, .visual-demo {
        padding: 30px 20px;
    }

    .nav-card {
        padding: 25px 20px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.8rem;
    }

    .section-title {
        font-size: 1.8rem;
    }
}

/* 动画效果 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeInUp 0.8s ease-out;
}