/* 全局变量 */
:root {
    --primary-color: #5C72E1;
    --secondary-color: #ebf0ff;
    --background-color: #f8f8f8;
    --text-color: #333333;
    --text-color-secondary: #666666;
    --text-color-light: #999999;
    --border-color: #eeeeee;
    --white: #ffffff;
    --danger-color: #ff4d4f;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.1);
}

/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-color);
    background-color: var(--background-color);
    line-height: 1.6;
}

img {
    max-width: 100%;
    height: auto;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s ease;
}

a:hover {
    color: #4757B3;
}

ul {
    list-style: none;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section-title {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 2rem;
    position: relative;
    color: var(--text-color);
}

.section-title:after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--primary-color);
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 500;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
}

.btn-primary:hover {
    background-color: #4757B3;
    color: var(--white);
}

.btn-secondary {
    background-color: var(--white);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

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

/* 头部导航 */
header {
    background-color: var(--white);
    box-shadow: var(--shadow-sm);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 100;
}

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

.logo h1 {
    font-size: 1.8rem;
    color: var(--primary-color);
    font-weight: 600;
}

nav ul {
    display: flex;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    color: var(--text-color);
    font-weight: 500;
}

nav ul li a:hover {
    color: var(--primary-color);
}

/* 英雄区域 */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(to bottom, #f6f8ff, var(--background-color));
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.hero-content {
    flex: 1;
    padding-right: 40px;
}

.hero-image {
    flex: 1;
    text-align: center;
}

.hero h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--text-color);
}

.hero p {
    font-size: 1.1rem;
    margin-bottom: 30px;
    color: var(--text-color-secondary);
}

.cta-buttons {
    display: flex;
    gap: 15px;
}

/* 功能区域 */
.features {
    padding: 80px 0;
    background-color: var(--white);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.feature-card {
    background: var(--white);
    border-radius: 10px;
    padding: 30px 20px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--secondary-color);
    border-radius: 50%;
}

.feature-icon img {
    max-width: 40px;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

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

/* 关于我们 */
.about {
    padding: 80px 0;
    background-color: var(--background-color);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

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

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

.download-description {
    font-size: 1.1rem;
    color: var(--text-color-secondary);
    max-width: 600px;
    margin: 0 auto 40px;
}

.download-options {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    align-items: center;
    padding: 15px 30px;
    background-color: var(--primary-color);
    color: var(--white);
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.download-btn:hover {
    background-color: #4757B3;
    color: var(--white);
}

.download-btn img {
    width: 24px;
    margin-right: 10px;
}

/* 页脚 */
footer {
    background-color: #2B2B2B;
    color: var(--white);
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--white);
}

.footer-logo p {
    color: #BBBBBB;
}

.footer-links h4 {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: var(--white);
}

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

.footer-links ul li a {
    color: #BBBBBB;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #444;
}

.footer-bottom p {
    color: #999;
    font-size: 0.9rem;
}

.icp-info {
    margin-top: 8px;
}

.icp-info a {
    color: #999;
    font-size: 0.85rem;
    text-decoration: none;
}

.icp-info a:hover {
    color: #ccc;
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }

    .hero-content {
        padding-right: 0;
        margin-bottom: 40px;
    }

    .cta-buttons {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    header .container {
        flex-direction: column;
    }

    .logo {
        margin-bottom: 15px;
    }

    nav ul {
        justify-content: center;
    }

    nav ul li {
        margin: 0 15px;
    }

    .hero {
        padding: 180px 0 60px;
    }

    .hero h2 {
        font-size: 2rem;
    }
}

@media (max-width: 576px) {
    .section-title {
        font-size: 1.8rem;
    }

    .hero h2 {
        font-size: 1.8rem;
    }

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