/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #409eff;
    --secondary-color: #67c23a;
    --text-color: #303133;
    --text-secondary: #606266;
    --border-color: #dcdfe6;
    --bg-color: #f5f7fa;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #fff;
}

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

/* 导航栏 */
.navbar {
    background: #fff;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

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

.nav-brand .logo {
    height: 50px;
    width: auto;
}

.nav-brand .brand-text {
    display: flex;
    flex-direction: column;
}

.nav-brand h1 {
    font-size: 24px;
    color: var(--primary-color);
    margin-bottom: 2px;
}

.nav-brand .tagline {
    font-size: 12px;
    color: var(--text-secondary);
}

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

.nav-menu a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

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

/* 首页横幅 */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    padding: 100px 0;
    text-align: center;
}

.hero-title {
    font-size: 48px;
    margin-bottom: 20px;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 24px;
    margin-bottom: 20px;
    opacity: 0.9;
}

.hero-description {
    font-size: 16px;
    max-width: 800px;
    margin: 0 auto 40px;
    line-height: 1.8;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    cursor: pointer;
}

.btn-primary {
    background: #fff;
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 255, 255, 0.3);
}

.btn-secondary {
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
}

.btn-secondary:hover {
    background: #fff;
    color: var(--primary-color);
}

/* 区块标题 */
.section-title {
    text-align: center;
    font-size: 36px;
    margin-bottom: 50px;
    color: var(--text-color);
}

/* 功能特色 */
.features {
    padding: 80px 0;
    background: #fff;
}

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

.feature-card {
    text-align: center;
    padding: 40px 20px;
    border-radius: 10px;
    transition: all 0.3s;
    background: var(--bg-color);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--text-color);
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* 服务模块 */
.services {
    padding: 80px 0;
    background: var(--bg-color);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.service-card {
    background: #fff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    transition: all 0.3s;
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
}

.service-card h3 {
    font-size: 20px;
    margin-bottom: 20px;
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 10px;
}

.service-card ul {
    list-style: none;
}

.service-card li {
    padding: 8px 0;
    color: var(--text-secondary);
    position: relative;
    padding-left: 20px;
}

.service-card li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}

/* 使用场景 */
.use-cases {
    padding: 80px 0;
    background: #fff;
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.use-case-card {
    text-align: center;
    padding: 40px 20px;
    border-radius: 10px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    transition: all 0.3s;
}

.use-case-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.4);
}

.use-case-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
}

.use-case-card p {
    line-height: 1.6;
    opacity: 0.9;
}

/* 下载区域 */
.download {
    padding: 80px 0;
    background: var(--bg-color);
    text-align: center;
}

.download-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.download-buttons {
    display: flex;
    gap: 30px;
    justify-content: center;
    margin-bottom: 50px;
}

.btn-download {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 20px 40px;
    background: #fff;
    color: var(--text-color);
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.download-icon {
    font-size: 40px;
}

.download-platform {
    font-size: 14px;
    color: var(--text-secondary);
}

.download-text {
    font-size: 18px;
    font-weight: 600;
}

.qrcode-section {
    margin-top: 40px;
}

.qrcode-placeholder {
    display: inline-block;
}

.qrcode-box {
    width: 200px;
    height: 200px;
    border: 2px dashed var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 20px auto;
    border-radius: 10px;
    background: #fff;
    color: var(--text-secondary);
}

/* 页脚 */
.footer {
    background: #2c3e50;
    color: #ecf0f1;
    padding: 50px 0 20px;
}

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

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

.footer-section p {
    margin-bottom: 10px;
    color: #bdc3c7;
}

.footer-section a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #95a5a6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero-title {
        font-size: 32px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .section-title {
        font-size: 28px;
    }

    .nav-menu {
        display: none;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .download-buttons {
        flex-direction: column;
        align-items: center;
    }

    .features-grid,
    .services-grid,
    .use-cases-grid {
        grid-template-columns: 1fr;
    }
}