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

body {
    font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: #2c3e50;
    background-color: #f0f2f5;
    overflow-x: hidden;
}

/* 科技风背景装饰 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 20% 80%, rgba(52, 152, 219, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 20%, rgba(46, 204, 113, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 40% 40%, rgba(155, 89, 182, 0.05) 0%, transparent 50%);
    z-index: -1;
    pointer-events: none;
}

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

/* 导航栏样式 */
header {
    background: rgba(44, 62, 80, 0.95);
    backdrop-filter: blur(10px);
    color: #fff;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.15);
    border-bottom: 1px solid rgba(52, 152, 219, 0.3);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.logo {
    display: flex;
    align-items: center;
}

.logo img {
    max-height: 60px;
    width: auto;
    display: block;
    filter: drop-shadow(0 2px 10px rgba(52, 152, 219, 0.3));
    transition: transform 0.3s ease;
}

.logo img:hover {
    transform: scale(1.05);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background-color: #3498db;
    border-radius: 3px;
    transition: all 0.3s ease;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin-left: 2rem;
}

.nav-menu li a {
    color: #ecf0f1;
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 0.5rem 0;
    position: relative;
    letter-spacing: 0.5px;
}

.nav-menu li a:hover {
    color: #3498db;
    transform: translateY(-2px);
}

.nav-menu li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #3498db, #2ecc71);
    transition: width 0.3s ease;
}

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



.btn {
    display: inline-block;
    padding: 1.2rem 2.5rem;
    background: linear-gradient(135deg, #3498db, #2980b9);
    color: #fff;
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 5px 20px rgba(52, 152, 219, 0.3);
    border: none;
    cursor: pointer;
    letter-spacing: 0.5px;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(52, 152, 219, 0.5);
}

.btn:hover::before {
    left: 100%;
}

/* 通用区块样式 */
section {
    padding: 60px 0;
    position: relative;
}

section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, #3498db, #2ecc71);
    border-radius: 2px;
}

h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    color: #2c3e50;
    font-size: 2.5rem;
    font-weight: 700;
    position: relative;
    display: inline-block;
    padding: 0 20px;
    background: linear-gradient(135deg, #2c3e50, #3498db);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: 1px;
}

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

/* 公司介绍样式 */
#about {
    background-color: #fff;
}

.about-content {
    max-width: 1000px;
    margin: 0 auto;
    font-size: 1.1rem;
    line-height: 1.8;
}

.about-brief {
    text-align: center;
    margin-bottom: 2rem;
    padding: 0 20px;
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.about-card {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(52, 152, 219, 0.1);
    position: relative;
    overflow: hidden;
}

.about-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, #3498db, #2ecc71);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.about-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(52, 152, 219, 0.15);
}

.about-card:hover::before {
    transform: scaleX(1);
}

.about-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: #3498db;
    transition: transform 0.3s ease;
}

.about-card:hover .about-icon {
    transform: scale(1.1);
}

.about-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.3rem;
    font-weight: 600;
}

.about-card p {
    color: #6c757d;
    font-size: 1rem;
    line-height: 1.6;
}

/* 服务项目样式 */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.service-item {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(52, 152, 219, 0.1);
    position: relative;
    overflow: hidden;
}

.service-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, #3498db, #2ecc71);
    border-radius: 2px;
}

.service-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(52, 152, 219, 0.15);
}

.service-item h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.3rem;
    font-weight: 600;
    margin-top: 1rem;
}

/* 交安工程案例轮播样式 */
#cases {
    background-color: #fff;
    padding: 4rem 0;
}

.carousel-container {
    position: relative;
    max-width: 800px;
    margin: 3rem auto;
    overflow: hidden;
    border-radius: 10px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.carousel-slide {
    display: flex;
    transition: transform 0.5s ease-in-out;
}

.carousel-item {
    min-width: 100%;
    position: relative;
}

.carousel-item img {
    width: 100%;
    height: 500px;
    object-fit: cover;
    display: block;
}

.carousel-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
    color: #fff;
    padding: 2rem 1rem 1rem;
    text-align: center;
}

.carousel-caption h3 {
    margin: 0;
    font-size: 1.5rem;
}

.carousel-controls {
    position: absolute;
    top: 50%;
    width: 100%;
    display: flex;
    justify-content: space-between;
    transform: translateY(-50%);
    padding: 0 1rem;
    box-sizing: border-box;
}

.carousel-control {
    background-color: rgba(0, 0, 0, 0.5);
    color: #fff;
    border: none;
    font-size: 2rem;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    transition: background-color 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.carousel-control:hover {
    background-color: rgba(0, 0, 0, 0.8);
}

.carousel-indicators {
    position: absolute;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 0.5rem;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    border: none;
    background-color: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.indicator.active {
    background-color: #fff;
    transform: scale(1.2);
}

/* 响应式轮播 */
@media (max-width: 768px) {
    .carousel-item img {
        height: 300px;
    }
    
    .carousel-control {
        font-size: 1.5rem;
        width: 40px;
        height: 40px;
    }
    
    .indicator {
        width: 10px;
        height: 10px;
    }
}

/* APP下载样式 */
#app {
    background-color: #f8f9fa;
}

.app-download {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 3rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}

.app-info {
    flex: 1;
    min-width: 300px;
}

.app-info h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 2rem;
}

.app-info p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.app-features {
    margin-bottom: 2rem;
}

.app-features h4 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.app-features ul {
    list-style-type: none;
    padding: 0;
}

.app-features li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    font-size: 1.1rem;
}

.app-features li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #3498db;
    font-weight: bold;
}

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

.btn-android {
    background-color: #4caf50;
}

.btn-android:hover {
    background-color: #45a049;
}

.btn-ios {
    background-color: #007aff;
}

.btn-ios:hover {
    background-color: #0056b3;
}

.download-note {
    background-color: #e8f4f8;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #3498db;
}

.download-note h4 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

.download-note p {
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.app-image {
    flex: 1;
    min-width: 200px;
    display: flex;
    justify-content: center;
}

.app-image img {
    max-width: 100%;
    height: auto;
    border-radius: 20px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

/* 联系我们样式 */
.contact-info {
    text-align: center;
    font-size: 1.1rem;
    line-height: 2;
    max-width: 600px;
    margin: 0 auto;
}

/* 页脚样式 */
footer {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    color: #fff;
    padding: 2rem 0;
    margin-top: 3rem;
    position: relative;
    overflow: hidden;
}

footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, #3498db, #2ecc71);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    padding: 0 20px;
}

.footer-info h3 {
    font-size: 1.3rem;
    margin-bottom: 0.8rem;
    color: #3498db;
}

.footer-info p {
    font-size: 0.9rem;
    color: #bdc3c7;
    line-height: 1.6;
}

.footer-links h4,
.footer-contact h4 {
    font-size: 1.1rem;
    margin-bottom: 0.8rem;
    color: #3498db;
}

.footer-links ul {
    list-style: none;
    padding: 0;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.footer-links a:hover {
    color: #3498db;
    margin-left: 5px;
}

.footer-contact p {
    margin-bottom: 0.5rem;
    line-height: 1.6;
    font-size: 0.9rem;
    color: #bdc3c7;
}

.footer-bottom {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(52, 152, 219, 0.2);
    font-size: 0.85rem;
    color: #95a5a6;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    padding-left: 20px;
    padding-right: 20px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }

    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: #2c3e50;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
    }

    .nav-menu.active {
        max-height: 500px;
        padding: 2rem 0;
    }

    .nav-menu li {
        margin-left: 0;
        margin: 0.5rem 0;
    }

    .app-download {
        flex-direction: column;
        text-align: center;
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    h2 {
        font-size: 2rem;
    }

    .btn {
        padding: 0.8rem 1.5rem;
        font-size: 1rem;
    }
}