/* 全局样式 */
:root {
    --primary-color: #F98686;
    --secondary-color: #FDA7A7;
    --accent-color: #FFC2C2;
    --text-color: #333333;
    --light-text-color: #666666;
    --bg-color: #ffffff;
    --secondary-bg-color: #FFF5F5;
    --border-color: #FFE0E0;
    --success-color: #FF7B7B;
    --box-shadow: 0 5px 20px rgba(249, 134, 134, 0.2);
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    overflow-x: hidden;
    letter-spacing: 0.01em;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 60px;
    position: relative;
    color: var(--primary-color);
    font-weight: 700;
    letter-spacing: 0.02em;
}

.section-title::after {
    content: "";
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--accent-color);
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 14px 32px;
    border-radius: 30px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: var(--transition);
    cursor: pointer;
    font-size: 0.95rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: 0 4px 15px rgba(249, 134, 134, 0.4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(249, 134, 134, 0.6);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    margin-left: 15px;
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-3px);
}

/* 导航栏 */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.98);
    box-shadow: 0 2px 15px rgba(249, 134, 134, 0.15);
    padding: 18px 0;
    z-index: 1000;
    transition: var(--transition);
}

header.scrolled {
    padding: 12px 0;
}

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

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-icon {
    width: 40px;
    height: 40px;
    margin-right: 12px;
    border-radius: 8px;
}

.logo h1 {
    font-size: 1.8rem;
    color: var(--primary-color);
    font-weight: 700;
}

.nav-links {
    display: flex;
}

.nav-links li {
    margin-left: 35px;
}

.nav-links a {
    font-weight: 500;
    position: relative;
    font-size: 1.05rem;
}

.nav-links a::after {
    content: "";
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

.nav-links a:hover::after {
    width: 100%;
}

.mobile-menu {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--primary-color);
}

/* 英雄区域 */
.hero {
    padding: 180px 0 120px;
    background: linear-gradient(135deg, rgba(253, 167, 167, 0.1), rgba(249, 134, 134, 0.1));
}

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

.hero-content {
    flex: 1;
    max-width: 500px;
}

.hero-content h1 {
    font-size: 3.2rem;
    line-height: 1.2;
    margin-bottom: 25px;
    color: var(--primary-color);
    font-weight: 800;
    letter-spacing: -0.02em;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--light-text-color);
    margin-bottom: 40px;
    line-height: 1.7;
}

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

.hero-image img {
    max-width: 100%;
    height: auto;
    max-height: 620px;
    border-radius: 20px;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.hero-image img.hero-device {
    border-radius: 25px;
    box-shadow: 0 20px 40px rgba(249, 134, 134, 0.25);
}

.hero-image img:hover {
    transform: translateY(-8px);
    box-shadow: 0 25px 50px rgba(249, 134, 134, 0.4);
}

/* 功能区 */
.features {
    padding: 140px 0;
    background-color: var(--secondary-bg-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
}

.feature-card {
    background-color: var(--bg-color);
    padding: 40px 30px;
    border-radius: 15px;
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(249, 134, 134, 0.1);
}

.feature-card:hover {
    transform: translateY(-15px);
    box-shadow: 0 20px 40px rgba(249, 134, 134, 0.2);
}

.feature-card i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 25px;
}

.feature-card h3 {
    font-size: 1.6rem;
    margin-bottom: 18px;
    color: var(--primary-color);
}

.feature-card p {
    color: var(--light-text-color);
    font-size: 1.05rem;
    line-height: 1.7;
}

/* 下载区域 */
.download {
    padding: 140px 0;
    background: linear-gradient(135deg, rgba(253, 167, 167, 0.15), rgba(249, 134, 134, 0.15));
    text-align: center;
}

.download-description {
    max-width: 700px;
    margin: 0 auto 60px;
    font-size: 1.25rem;
    color: var(--light-text-color);
    line-height: 1.7;
}

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

.download-btn {
    display: flex;
    align-items: center;
    background-color: #333;
    color: white;
    padding: 18px 40px;
    border-radius: 12px;
    transition: var(--transition);
    box-shadow: var(--box-shadow);
    width: 240px;
}

.download-btn:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 30px rgba(249, 134, 134, 0.4);
    background-color: var(--primary-color);
}

.download-btn i {
    font-size: 2.8rem;
    margin-right: 18px;
}

.download-btn span {
    text-align: left;
}

.download-btn small {
    display: block;
    font-size: 0.75rem;
    opacity: 0.8;
    margin-bottom: 2px;
}

/* 关于我们 */
.about {
    padding: 140px 0;
    background-color: var(--secondary-bg-color);
    margin-top: 0;
}

.about-description {
    max-width: 800px;
    margin: 0 auto 60px;
    text-align: center;
    font-size: 1.15rem;
    color: var(--light-text-color);
    line-height: 1.8;
}

.about-values {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 40px;
}

.value-item {
    flex: 1;
    min-width: 280px;
    text-align: center;
    padding: 40px 30px;
    background-color: var(--bg-color);
    border-radius: 15px;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    border: 1px solid rgba(249, 134, 134, 0.1);
}

.value-item:hover {
    transform: translateY(-15px);
    box-shadow: 0 20px 40px rgba(249, 134, 134, 0.2);
}

.value-item i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 25px;
}

.value-item h3 {
    margin-bottom: 15px;
    color: var(--primary-color);
    font-size: 1.6rem;
}

.value-item p {
    color: var(--light-text-color);
    font-size: 1.05rem;
    line-height: 1.7;
}

/* 页脚 */
footer {
    background-color: #F57F7F;
    color: white;
    padding: 80px 0 25px;
}

.footer-content {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    margin-bottom: 50px;
}

.footer-logo {
    flex: 1;
    min-width: 200px;
    margin-bottom: 30px;
}

.footer-logo h2 {
    font-size: 2rem;
    margin-bottom: 15px;
}

.footer-links {
    flex: 2;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
}

.footer-links-column {
    margin-bottom: 30px;
    min-width: 200px;
}

.footer-links-column h3 {
    margin-bottom: 20px;
    font-size: 1.3rem;
    position: relative;
    padding-bottom: 12px;
}

.footer-links-column h3::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: rgba(255, 255, 255, 0.5);
}

.footer-links-column ul li {
    margin-bottom: 12px;
}

.footer-links-column ul li a:hover {
    color: rgba(255, 255, 255, 0.8);
}

.footer-links-column ul li i {
    margin-right: 10px;
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    padding-top: 25px;
    text-align: center;
    font-size: 0.9rem;
    opacity: 0.9;
}

.footer-bottom a {
    color: white;
    text-decoration: underline;
}

.footer-bottom a:hover {
    text-decoration: none;
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .features-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
}

@media (max-width: 992px) {
    html {
        font-size: 15px;
    }
    
    .hero {
        padding: 150px 0 100px;
    }
    
    .hero .container {
        flex-direction: column;
        text-align: center;
        gap: 50px;
    }
    
    .hero-content {
        margin-bottom: 0;
    }
    
    .hero-image img {
        max-height: 550px;
    }
    
    .cta-buttons {
        justify-content: center;
    }
    
    .features, .download, .about {
        padding: 100px 0;
    }
    
    .features-grid {
        grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
        gap: 30px;
    }
    
    .about-values {
        flex-direction: column;
        align-items: center;
    }
    
    .value-item {
        width: 100%;
        max-width: 450px;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    header {
        padding: 15px 0;
    }
    
    .nav-links {
        display: none;
    }
    
    .mobile-menu {
        display: block;
    }
    
    .section-title {
        font-size: 2.2rem;
        margin-bottom: 50px;
    }
    
    .hero-content h1 {
        font-size: 2.8rem;
    }
    
    .hero-content p {
        font-size: 1.1rem;
    }
    
    .hero-image img {
        max-height: 450px;
    }
    
    .feature-card,
    .value-item {
        padding: 30px 20px;
    }
    
    .footer-content {
        flex-direction: column;
    }
    
    .download-btn {
        width: 220px;
        padding: 15px 30px;
    }
    
    .download-btn i {
        font-size: 2.5rem;
    }
}

@media (max-width: 576px) {
    .hero {
        padding: 130px 0 80px;
    }
    
    .section-title::after {
        width: 50px;
    }
    
    .download-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn-secondary {
        margin-left: 0;
        margin-top: 15px;
    }
    
    .hero-image img {
        max-height: 380px;
        border-radius: 15px;
    }
    
    .features-grid, .about-values {
        gap: 25px;
    }
    
    .feature-card:hover, .value-item:hover {
        transform: translateY(-8px);
    }
}