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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
    line-height: 1.5;
    font-weight: 400;
    color: #1f2937;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* 颜色变量 */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #f97316;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1.25rem;
    border-radius: 9999px;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    font-size: 0.875rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

.btn-outline:hover {
    background-color: #eff6ff;
}

.btn-large {
    padding: 0.75rem 2rem;
    font-size: 1rem;
}

/* 导航栏 */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 50;
    transition: all 0.3s ease;
    background-color: transparent;
    padding: 1.25rem 0;
}

.nav.scrolled {
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    padding: 0.75rem 0;
}

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

.logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.logo i {
    margin-right: 0.5rem;
}

.nav-links {
    display: none;
    align-items: center;
    gap: 2rem;
}

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

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-buttons {
    display: none;
    align-items: center;
    gap: 1rem;
}

.mobile-menu-btn {
    display: block;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-secondary);
    cursor: pointer;
}

.mobile-menu {
    display: none;
    flex-direction: column;
    background-color: white;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    padding: 1rem;
    gap: 0.5rem;
}

.mobile-menu.show {
    display: flex;
}

.mobile-link {
    padding: 0.75rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-bottom: 1px solid var(--border-color);
}

.mobile-btn {
    margin: 0.5rem 1rem;
}

/* Banner区域 */
.banner {
    padding-top: 6rem;
    padding-bottom: 4rem;
    background: linear-gradient(135deg, #eff6ff, #e0e7ff);
}

.banner-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2.5rem;
}

.banner-text h1 {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: 1rem;
}

.banner-text .text-blue {
    color: var(--primary-color);
}

.banner-text p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 32rem;
}

.banner-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.banner-image img {
    width: 100%;
    max-width: 500px;
    height: 300px;
    object-fit: cover;
    border-radius: 1rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

/* 关于区域 */
.about {
    padding: 4rem 0;
    background-color: var(--bg-white);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header h2 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.section-header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 42rem;
    margin: 0 auto;
}

.about-content {
    display: flex;
    flex-direction: column;
    gap: 3rem;
    align-items: center;
}

.about-image img {
    width: 100%;
    max-width: 500px;
    border-radius: 1rem;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.about-text h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.features-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin: 1.5rem 0;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.feature-item i {
    color: #10b981;
    font-size: 1.25rem;
}

.learn-more {
    color: var(--primary-color);
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.learn-more:hover {
    text-decoration: underline;
}

/* 功能特点 */
.features {
    padding: 4rem 0;
    background-color: var(--bg-light);
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

.feature-card {
    background-color: var(--bg-white);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-0.5rem);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    width: 3.5rem;
    height: 3.5rem;
    background-color: #eff6ff;
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.feature-icon i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

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

/* 下载区域 */
.download {
    padding: 4rem 0;
    background: linear-gradient(135deg, var(--primary-color), #4f46e5);
    color: white;
}

.download-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3rem;
}

.download-text h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.download-text p {
    color: #dbeafe;
    margin-bottom: 2rem;
    max-width: 32rem;
}

.download-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background-color: white;
    color: var(--primary-color);
    border: none;
    border-radius: 0.75rem;
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.download-btn:hover {
    background-color: #f8fafc;
    transform: translateY(-1px);
}

.download-btn i {
    font-size: 1.5rem;
}

.download-text-small {
    font-size: 0.75rem;
    color: #6b7280;
}

.download-text-large {
    font-size: 1rem;
    font-weight: 700;
}

.qr-code {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.qr-container {
    background-color: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border-radius: 0.5rem;
    padding: 1rem;
}

.qr-container img {
    width: 8rem;
    height: 8rem;
}

.qr-code p {
    color: #dbeafe;
    margin: 0;
}

.download-image img {
    width: 100%;
    max-width: 320px;
    border-radius: 1.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    border: 8px solid rgba(255, 255, 255, 0.1);
}

/* 页脚 */
.footer {
    background-color: #111827;
    color: white;
    padding: 4rem 0 1.5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    margin-bottom: 4rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.footer-logo i {
    margin-right: 0.5rem;
}

.footer-section p {
    color: #9ca3af;
    margin-bottom: 1.5rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 2.5rem;
    height: 2.5rem;
    background-color: #374151;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.social-links a:hover {
    background-color: var(--primary-color);
}

.footer-section h4 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

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

.footer-section li {
    margin-bottom: 0.75rem;
}

.footer-section a {
    color: #9ca3af;
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.footer-section li i {
    margin-right: 0.75rem;
    color: #9ca3af;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 2rem;
    text-align: center;
    color: #6b7280;
    font-size: 0.875rem;
}

.footer-bottom p {
    margin-bottom: 0.5rem;
}

/* 移动端底部菜单 */
.mobile-bottom-menu {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: white;
    box-shadow: 0 -4px 6px -1px rgba(0, 0, 0, 0.1);
    display: flex;
    z-index: 40;
    border-top: 1px solid var(--border-color);
}

.bottom-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 0.75rem;
    border: none;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.bottom-btn i {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

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

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

/* 响应式设计 */
@media (min-width: 768px) {
    .nav-links {
        display: flex;
    }
    
    .nav-buttons {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: none;
    }
    
    .mobile-bottom-menu {
        display: none;
    }
    
    .banner {
        padding-top: 8rem;
        padding-bottom: 6rem;
    }
    
    .banner-content {
        flex-direction: row;
        align-items: center;
    }
    
    .banner-text h1 {
        font-size: 3rem;
    }
    
    .banner-buttons {
        flex-direction: row;
    }
    
    .about-content {
        flex-direction: row;
        align-items: center;
    }
    
    .about-text,
    .about-image {
        flex: 1;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .download-content {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
    }
    
    .download-text,
    .download-image {
        flex: 1;
    }
    
    .download-buttons {
        flex-direction: row;
    }
    
    .footer-content {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (min-width: 1024px) {
    .banner-text h1 {
        font-size: 3.75rem;
    }
    
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .section-header h2 {
        font-size: 2.25rem;
    }
}

/* 动画效果 */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 隐藏移动端菜单 */
body {
    padding-bottom: 70px;
}

@media (min-width: 768px) {
    body {
        padding-bottom: 0;
    }
}