* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

/* 头部区域 */
.header {
    text-align: center;
    padding: 60px 20px 40px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.logo {
    width: 120px;
    height: 120px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 25px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    color: white;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
    animation: float 3s ease-in-out infinite;
    overflow: hidden;
}

.logo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-10px);
    }
}

.app-name {
    font-size: 32px;
    font-weight: bold;
    color: #2d3748;
    margin-bottom: 10px;
}

.app-tagline {
    font-size: 16px;
    color: #718096;
    margin-bottom: 30px;
}

/* 下载按钮 */
.download-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: center;
    align-items: center;
    margin-bottom: 20px;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
    padding: 0 20px;
}

.btn {
    flex: 0 0 auto;
    min-width: 220px;
    max-width: 280px;
    padding: 15px 20px;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    white-space: nowrap;
    box-sizing: border-box;
}

/* 大屏幕时按钮等宽 */
@media (min-width: 769px) {
    .download-buttons {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .btn {
        flex: 0 1 calc(25% - 15px);
        min-width: 200px;
        max-width: 240px;
    }
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

.btn-secondary {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
    transform: translateY(-2px);
}

.btn-invite {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(240, 147, 251, 0.4);
}

.btn-invite:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(240, 147, 251, 0.6);
}

.btn-official {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(79, 172, 254, 0.4);
}

.btn-official:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(79, 172, 254, 0.6);
}

/* 应用信息 */
.app-info {
    padding: 40px 20px;
}

.info-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
    text-align: center;
}

.stat-item {
    padding: 20px;
    background: #f7fafc;
    border-radius: 12px;
}

.stat-value {
    font-size: 28px;
    font-weight: bold;
    color: #667eea;
    margin-bottom: 5px;
}

.stat-label {
    font-size: 14px;
    color: #718096;
}

/* 应用介绍 */
.app-description {
    margin-bottom: 40px;
}

.section-title {
    font-size: 24px;
    font-weight: bold;
    color: #2d3748;
    margin-bottom: 20px;
    text-align: center;
}

.description-text {
    line-height: 1.8;
    color: #4a5568;
    margin-bottom: 15px;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.feature-item {
    padding: 25px;
    background: linear-gradient(135deg, #4a5f7f 0%, #3a4d63 100%);
    border-radius: 15px;
    color: white;
    text-align: center;
    transition: transform 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 40px;
    margin-bottom: 15px;
}

.feature-title {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-desc {
    font-size: 15px;
    line-height: 1.6;
    color: #d4dce6;
}

/* 截图轮播 - iPhone 17 Pro 设计 */
.screenshots-section {
    padding: 60px 20px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

/* iPhone 17 Pro 外壳容器 */
.phone-mockup {
    max-width: 400px;
    margin: 30px auto 0;
    position: relative;
    padding: 6px;
    background: linear-gradient(145deg, #5a5a5a, #3d3d3d);
    border-radius: 55px;
    box-shadow: 
        0 30px 80px rgba(0, 0, 0, 0.35),
        inset 0 0 0 1px rgba(255, 255, 255, 0.1),
        inset 0 1px 2px rgba(255, 255, 255, 0.2);
}

/* 钛金属边框 */
.phone-frame {
    background: linear-gradient(145deg, #e8e8e8, #c5c5c5);
    border-radius: 50px;
    padding: 2px;
    box-shadow: 
        inset 0 0 2px rgba(255, 255, 255, 0.5),
        inset 0 -2px 4px rgba(0, 0, 0, 0.1);
}

/* 屏幕区域 */
.phone-screen {
    background: #000;
    border-radius: 48px;
    overflow: hidden;
    position: relative;
    box-shadow: 
        inset 0 0 1px rgba(255, 255, 255, 0.1),
        0 0 20px rgba(0, 0, 0, 0.3);
}

/* 灵动岛 (Dynamic Island) */
.dynamic-island {
    position: absolute;
    top: 12px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 32px;
    background: #0a0a0a;
    border-radius: 20px;
    z-index: 20;
    box-shadow: 
        0 2px 10px rgba(0, 0, 0, 0.8),
        inset 0 1px 1px rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 15px;
}

/* 前置摄像头 */
.camera {
    width: 10px;
    height: 10px;
    background: radial-gradient(circle, #1a3a52 0%, #0d1f2d 100%);
    border-radius: 50%;
    box-shadow: 
        0 0 2px rgba(100, 200, 255, 0.3),
        inset 0 0 3px rgba(0, 0, 0, 0.8);
    position: relative;
}

.camera::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 3px;
    height: 3px;
    background: rgba(255, 255, 255, 0.4);
    border-radius: 50%;
}

/* Face ID传感器 */
.sensor {
    width: 40px;
    height: 6px;
    background: #0d0d0d;
    border-radius: 3px;
}

/* 轮播容器 */
.carousel-container {
    position: relative;
    overflow: hidden;
}

.carousel-wrapper {
    position: relative;
    padding-bottom: 216%; /* iPhone 比例 */
    height: 0;
}

.carousel-slides {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.carousel-slide {
    min-width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-size: 24px;
    font-weight: 600;
}

.carousel-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 左右切换按钮 */
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(255, 255, 255, 0.95);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 15;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
    color: #333;
    font-weight: 300;
    backdrop-filter: blur(10px);
}

.carousel-btn:hover {
    background: white;
    transform: translateY(-50%) scale(1.08);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.carousel-btn:active {
    transform: translateY(-50%) scale(0.98);
}

.carousel-btn.prev {
    left: -70px;
}

.carousel-btn.next {
    right: -70px;
}

/* 指示点 */
.carousel-indicators {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 6px;
    z-index: 15;
    background: rgba(0, 0, 0, 0.3);
    padding: 8px 12px;
    border-radius: 20px;
    backdrop-filter: blur(10px);
}

.indicator {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.indicator.active {
    background: white;
    width: 20px;
    border-radius: 3px;
}

.indicator:hover {
    background: rgba(255, 255, 255, 0.8);
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 30px 20px;
    background: #2d3748;
    color: white;
}

.footer-links {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-bottom: 15px;
    flex-wrap: wrap;
}

.footer-links a {
    color: #a0aec0;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
}

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

.copyright {
    font-size: 14px;
    color: #718096;
}

/* 响应式设计 */
/* 小屏幕：2×2布局，居中显示 */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    .container {
        border-radius: 15px;
    }

    .header {
        padding: 40px 20px 30px;
    }

    .logo {
        width: 100px;
        height: 100px;
        font-size: 40px;
    }

    .app-name {
        font-size: 24px;
    }

    .app-tagline {
        font-size: 14px;
    }

    .download-buttons {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 12px;
        max-width: 500px;
        padding: 0 15px;
    }

    .btn {
        flex: 0 1 calc(50% - 6px);
        min-width: 0;
        max-width: none;
        padding: 13px 15px;
        font-size: 14px;
    }

    .section-title {
        font-size: 20px;
    }

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

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

    .phone-mockup {
        max-width: 340px;
    }

    .carousel-btn {
        width: 44px;
        height: 44px;
        font-size: 20px;
    }

    .carousel-btn.prev {
        left: -60px;
    }

    .carousel-btn.next {
        right: -60px;
    }

    .feature-title {
        font-size: 20px;
    }

    .feature-desc {
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    .screenshots-section {
        padding: 40px 10px;
    }

    .download-buttons {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
        padding: 0 10px;
    }

    .btn {
        padding: 12px 10px;
        font-size: 13px;
    }

    .phone-mockup {
        max-width: 300px;
    }

    .carousel-btn.prev {
        left: 5px;
    }

    .carousel-btn.next {
        right: 5px;
    }

    .carousel-btn {
        width: 38px;
        height: 38px;
        font-size: 18px;
        background: rgba(255, 255, 255, 0.9);
    }

    .feature-item {
        padding: 20px;
    }

    .feature-icon {
        font-size: 32px;
    }

    .feature-title {
        font-size: 18px;
    }
}

@media (max-width: 380px) {
    .phone-mockup {
        max-width: 280px;
    }

    .dynamic-island {
        width: 100px;
        height: 28px;
    }
}