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

:root {
    --primary-color: #4A90D9;
    --primary-dark: #357ABD;
    --secondary-color: #6C757D;
    --text-color: #333;
    --text-light: #666;
    --bg-color: #fff;
    --bg-light: #f8f9fa;
    --border-color: #e9ecef;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-lg: 0 5px 30px rgba(0,0,0,0.15);
}

html {
    scroll-behavior: smooth;
}

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

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    z-index: 1000;
    padding: 15px 0;
}

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

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-logo {
    width: 40px;
    height: 40px;
    border-radius: 8px;
}

.nav-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.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);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-color);
    transition: 0.3s;
}

/* Hero 区域 */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
}

.hero-text {
    flex: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.hero-subtitle {
    font-size: 1.5rem;
    opacity: 0.9;
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.1rem;
    opacity: 0.85;
    margin-bottom: 30px;
    line-height: 1.8;
}

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

.btn {
    padding: 12px 30px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    display: inline-block;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

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

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.hero-image img {
    max-width: 300px;
    filter: drop-shadow(0 20px 40px rgba(0,0,0,0.3));
}

/* 功能特性 */
.features {
    padding: 80px 0;
    background: var(--bg-light);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: var(--text-color);
}

.section-desc {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 50px;
}

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

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

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

.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 30px;
    height: 30px;
    color: white;
}

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

.feature-card p {
    color: var(--text-light);
    line-height: 1.7;
}

/* 应用截图 */
.screenshots {
    padding: 80px 0;
}

.screenshots-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
}

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

.screenshot-item img {
    width: 100%;
    max-width: 250px;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    transition: transform 0.3s;
}

.screenshot-item:hover img {
    transform: scale(1.05);
}

.screenshot-caption {
    margin-top: 15px;
    color: var(--text-light);
    font-size: 0.95rem;
}

/* 下载区域 */
.download {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.download .section-title,
.download .section-desc {
    color: white;
}

.download-buttons {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-top: 40px;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(10px);
    padding: 30px 50px;
    border-radius: 12px;
    text-decoration: none;
    color: white;
    transition: all 0.3s;
    border: 2px solid rgba(255,255,255,0.3);
}

.download-btn:hover {
    background: rgba(255,255,255,0.25);
    transform: translateY(-5px);
}

.download-btn svg {
    width: 40px;
    height: 40px;
}

.download-btn span {
    font-size: 1.2rem;
    font-weight: 600;
}

.download-btn small {
    font-size: 0.9rem;
    opacity: 0.8;
}

.download-note {
    margin-top: 30px;
    opacity: 0.8;
}

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

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

.about-text h3 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.about-text p {
    margin-bottom: 15px;
    color: var(--text-light);
    line-height: 1.8;
}

.about-info {
    margin-top: 30px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.info-item {
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.info-item strong {
    display: block;
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.info-item span {
    color: var(--text-color);
    font-weight: 500;
}

/* 联系我们 */
.contact {
    padding: 80px 0;
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    max-width: 600px;
    margin: 0 auto;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    padding: 25px;
    background: var(--bg-light);
    border-radius: 12px;
}

.contact-item svg {
    width: 24px;
    height: 24px;
    color: var(--primary-color);
    flex-shrink: 0;
}

.contact-item h4 {
    margin-bottom: 5px;
    color: var(--text-color);
}

.contact-item p {
    color: var(--text-light);
}

/* 页脚 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 40px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-copy {
    text-align: right;
    opacity: 0.8;
    font-size: 0.9rem;
}

.footer-copy p {
    margin-bottom: 5px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow);
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-content {
        flex-direction: column;
        text-align: center;
    }

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

    .hero-subtitle {
        font-size: 1.2rem;
    }

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

    .section-title {
        font-size: 2rem;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .screenshots-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-copy {
        text-align: center;
    }
}