:root {
    --primary: #00a8ff;
    --secondary: #192a56;
    --dark: #0c1427;
    --light: #f5f6fa;
    --accent: #9c88ff;
    --card-bg: rgba(255, 255, 255, 0.03);
    --card-hover: rgba(255, 255, 255, 0.07);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}
/* 滚动动画：元素进入视口时的渐入效果 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}
/* 滚动条样式优化 */
        ::-webkit-scrollbar {
            width: 8px;
            height: 8px;
        }

        ::-webkit-scrollbar-track {
            background: var(--secondary);
        }

        ::-webkit-scrollbar-thumb {
            background: var(--primary);
            border-radius: 4px;
            transition: background 0.3s ease;
        }

        ::-webkit-scrollbar-thumb:hover {
            background: var(--accent);
        }


/* 鼠标跟随无人机样式 */
 .drone-follower {
    position: fixed !important;
    top: 0 !important;
    left: 0 !important;
    color: var(--primary) !important;
    pointer-events: none !important;
    z-index: 9999 !important;
    opacity: 0.9 !important;
    transition: transform 0.15s ease-out !important;
    transform-origin: center center !important;
    /* animation: droneFloat 3s infinite ease-in-out !important; */
    /* 移除固定 width/height，改为 JS 动态设置 */
}

 /* 无人机自身悬浮动画 */
 @keyframes droneFloat {

     0%,
     100% {
         transform: translateY(0) rotate(15deg) !important;
     }

     50% {
         transform: translateY(-8px) rotate(15deg) !important;
     }
 }
/* 模块一：全屏智慧城市视频 */
.sc-video-section {
    position: relative;
    height: 100vh;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.sc-video-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
}

.sc-video-bg video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: brightness(0.5);
}

.sc-video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(12, 20, 39, 0.8) 0%, rgba(25, 42, 86, 0.8) 100%);
    z-index: -1;
}

.sc-video-content {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0 20px;
    animation: fadeInUp 1s ease-out;
}
.sc-video-content .btn{
    max-width: 190px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.sc-video-content h2 {
    max-width: 800px;
    font-size: 3.5rem;
    margin-bottom: 20px;
    background: linear-gradient(90deg, var(--light), var(--primary));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.sc-video-content p {
    max-width: 800px;
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 30px;
}

.btn {
    display: inline-block;
    background: var(--primary);
    color: var(--light);
    padding: 12px 30px;
    border-radius: 30px;
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
}

.btn:hover {
    background: var(--accent);
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 168, 255, 0.3);
}

.sc-video-particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.sc-particle {
    position: absolute;
    background: rgba(0, 168, 255, 0.2);
    border-radius: 50%;
    animation: floatSC 10s infinite ease-in-out;
}

@keyframes floatSC {
    0%, 100% {
        transform: translateY(0) translateX(0) rotate(0deg);
        opacity: 0.6;
    }
    50% {
        transform: translateY(-40px) translateX(20px) rotate(15deg);
        opacity: 0.9;
    }
}

/* 通用section样式 */
.section-title {
    text-align: center;
    margin-bottom: 80px;
    color: var(--light);
}

.section-title h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.section-title p {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.7);
    max-width: 600px;
    margin: 0 auto;
}

.container {
    max-width: 1500px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 模块二：智慧城市管理平台概览 */
.sc-platform-section {
    background-color: var(--secondary);
    padding: 120px 0;
}
.sc-platform-section .container{
    max-width: 1700px;
    width: 100%;
}
.platform-single-img {
    margin: 0 auto 30px;
    max-width: 1700px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.platform-single-img img {
    width: 100%;
    height: auto;
    transition: transform 0.8s ease;
}

.platform-single-img:hover img {
    transform: scale(1.05);
}

.platform-desc {
    max-width: 800px;
    margin: 0 auto;
    color: rgba(255, 255, 255, 0.8);
    font-size: 1.1rem;
    line-height: 1.8;
}


/* 模块三：核心子系统展示 */
.sc-systems-section {
    background-color: var(--dark);
    padding: 120px 0;
}

.systems-carousel {
    display: flex;
    overflow-x: auto;
    gap: 30px;
    padding-bottom: 20px;
    scroll-snap-type: x mandatory;
}

.systems-carousel::-webkit-scrollbar {
    height: 6px;
}

.systems-carousel::-webkit-scrollbar-track {
    background: var(--card-bg);
    border-radius: 10px;
}

.systems-carousel::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 10px;
}

.system-card {
    flex: 0 0 400px;
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.5s ease;
    box-shadow: var(--shadow);
    scroll-snap-align: center;
}

.system-card:hover {
    transform: translateY(-10px);
    background: var(--card-hover);
}

.system-img {
    height: 220px;
    overflow: hidden;
}

.system-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.8s ease;
}

.system-card:hover .system-img img {
    transform: scale(1.1);
}

.system-content {
    padding: 25px;
}

.system-title {
    font-size: 1.5rem;
    color: var(--light);
    margin-bottom: 15px;
}

.system-desc {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 20px;
}

.system-detail-btn {
    background: transparent;
    border: 1px solid var(--primary);
    color: var(--primary);
    padding: 10px 20px;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.system-detail-btn:hover {
    background: var(--primary);
    color: var(--light);
}
/* 模块三：3D翻转卡片 */
.flip-card {
    background-color: transparent;
    perspective: 1000px;
    flex: 0 0 320px; /* 卡片宽度 */
}

.flip-card-inner {
    position: relative;
    width: 100%;
    height: 350px; /* 卡片高度统一 */
    text-align: center;
    transition: transform 0.6s;
    transform-style: preserve-3d;
    box-shadow: var(--shadow);
    border-radius: 12px;
}

.flip-card:hover .flip-card-inner {
    transform: rotateY(180deg);
}

.flip-card-front, .flip-card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    border-radius: 12px;
    overflow: hidden;
}

.flip-card-front {
    background-color: var(--card-bg);
}

.flip-card-back {
    background-color: var(--card-hover);
    color: var(--light);
    transform: rotateY(180deg);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 25px;
}

.system-img {
    height: 200px; /*  front 图高度 */
    overflow: hidden;
}

.system-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.8s ease;
}

.flip-card:hover .system-img img {
    transform: scale(1.1);
}

.system-content-front {
    padding: 20px;
}

.system-title {
    font-size: 1.3rem;
    color: var(--light);
    margin: 0;
}

.system-desc-back {
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.6;
}

/* 轮播容器样式优化 */
.systems-carousel {
    display: flex;
    overflow-x: auto;
    gap: 20px;
    padding-bottom: 20px;
    scroll-snap-type: x mandatory;
}

.systems-carousel::-webkit-scrollbar {
    height: 6px;
}

.systems-carousel::-webkit-scrollbar-track {
    background: var(--card-bg);
    border-radius: 10px;
}

.systems-carousel::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 10px;
}
/* 模块四：成功案例展示 */
.sc-cases-section {
    background-color: var(--secondary);
    padding: 120px 0;
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

.case-card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.5s ease;
}

.case-card:hover {
    transform: translateY(-10px);
    background: var(--card-hover);
}

.case-header {
    padding: 25px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.case-title {
    font-size: 1.3rem;
    color: var(--light);
    margin: 0;
}

.case-content {
    padding: 25px;
}

.case-media {
    margin-bottom: 20px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.case-media img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    transition: transform 0.5s ease;
}

.case-card:hover .case-media img {
    transform: scale(1.05);
}

.case-desc {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 25px;
    line-height: 1.6;
}

.case-highlights h4, .case-value h4 {
    font-size: 1.2rem;
    color: var(--primary);
    margin-bottom: 15px;
}

.case-highlights ul, .case-value ul {
    list-style: none;
    padding: 0;
}

.case-highlights li, .case-value li {
    position: relative;
    padding-left: 25px;
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.8);
}

.case-highlights li::before, .case-value li::before {
    content: "•";
    color: var(--primary);
    position: absolute;
    left: 0;
    font-size: 1.2rem;
}
/* 案例轮播容器 */
.case-carousel {
    position: relative;
    height: 750px; /* 增加高度，容纳长内容 */
    overflow: hidden;
    margin-bottom: 40px;
}

/* 轮播项 */
.case-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transform: translateY(20px) scale(0.95);
    transition: opacity 0.6s ease, transform 0.6s ease;
    z-index: 1;
}

.case-slide.active {
    opacity: 1;
    transform: translateY(0) scale(1);
    z-index: 10;
}

/* 轮播项切换中（用于中间态动画） */
.case-slide.transition {
    transition: opacity 0.6s ease, transform 0.6s ease;
}

/* 案例卡片 */
.case-card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.case-header {
    padding: 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    background-color: var(--dark);
}

.case-title {
    font-size: 1.3rem;
    color: var(--light);
    margin: 0;
}

.case-content {
    padding: 20px;
    overflow-y: auto;
    flex-grow: 1;
}

.case-media {
    margin-bottom: 15px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 10px;
}

.case-media img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    transition: transform 0.5s ease;
}

.case-card:hover .case-media img {
    transform: scale(1.03);
}

.case-desc {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 20px;
    line-height: 1.6;
}

.case-highlights h4, .case-value h4 {
    font-size: 1.1rem;
    color: var(--primary);
    margin-bottom: 10px;
}

.case-highlights ul, .case-value ul {
    list-style: none;
    padding: 0;
}

.case-highlights li, .case-value li {
    position: relative;
    padding-left: 25px;
    margin-bottom: 8px;
    color: rgba(255, 255, 255, 0.8);
}

.case-highlights li::before, .case-value li::before {
    content: "•";
    color: var(--primary);
    position: absolute;
    left: 0;
    font-size: 1.1rem;
}

/* 轮播导航按钮 */
.carousel-nav {
    display: flex;
    justify-content: center;
    gap: 20px;
}

.carousel-btn {
    background: var(--primary);
    color: var(--light);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.3s ease, transform 0.3s ease;
    box-shadow: var(--shadow);
}

.carousel-btn:hover {
    background: var(--accent);
    transform: scale(1.05);
}

.carousel-btn i {
    font-size: 1.2rem;
}

/* 页脚 */
footer {
    background-color: var(--dark);
    padding: 80px 0 30px;
    color: rgba(255, 255, 255, 0.7);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.footer-column h3 {
    font-size: 1.5rem;
    color: var(--light);
    margin-bottom: 20px;
}

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

.footer-links li {
    margin-bottom: 10px;
}

.footer-links li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links li a:hover {
    color: var(--primary);
}

.copyright {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* 动画关键帧 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式调整 */
@media (max-width: 992px) {

    .sc-video-content h2 {
        font-size: 2.5rem;
    }

    .section-title h2 {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .sc-video-content h2 {
        font-size: 2rem;
    }

    .sc-video-content p {
        font-size: 1rem;
    }

    .platform-card, .system-card, .scenario-card {
        flex: 0 0 100%;
    }
}