/* 重置样式和基本设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #1a1a1a;
    --secondary-color: #2d2d2d;
    --accent-color: #404040;
    --text-color: #ffffff;
    --light-text: #cccccc;
    --bg-color: #0d0d0d;
    --card-bg: #1a1a1a;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    --border-radius: 12px;
    --hover-color: #333333;
    --border-color: #333333;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--bg-color);
    overflow-x: hidden;
    font-style: normal;
    letter-spacing: 0.2px;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: linear-gradient(135deg, 
        rgba(0, 0, 0, 0.3) 0%, 
        rgba(15, 15, 15, 0.25) 50%, 
        rgba(25, 25, 25, 0.2) 100%);
    backdrop-filter: blur(15px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

/* 在视频区域时透明 */
.navbar.in-video {
    background: transparent;
    backdrop-filter: none;
    box-shadow: none;
    border-bottom: none;
}

/* 在视频区域时增强文字阴影 */
.navbar.in-video .nav-logo {
    text-shadow: 
        0 0 10px rgba(0, 0, 0, 1),
        0 0 20px rgba(0, 0, 0, 1),
        0 2px 4px rgba(0, 0, 0, 0.9),
        2px 2px 8px rgba(0, 0, 0, 0.8),
        -2px -2px 8px rgba(0, 0, 0, 0.8);
}

.navbar.in-video .nav-link {
    text-shadow: 
        0 0 8px rgba(0, 0, 0, 1),
        0 0 15px rgba(0, 0, 0, 1),
        0 2px 4px rgba(0, 0, 0, 0.9),
        1px 1px 6px rgba(0, 0, 0, 0.8),
        -1px -1px 6px rgba(0, 0, 0, 0.8);
}

/* 滚动时导航栏效果 */
.navbar.scrolled {
    background: linear-gradient(135deg, 
        rgba(0, 0, 0, 0.95) 0%, 
        rgba(10, 10, 10, 0.9) 50%, 
        rgba(20, 20, 20, 0.85) 100%);
    backdrop-filter: blur(25px);
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.7);
    border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

/* 在视频区域滚动时仍保持透明 */
.navbar.scrolled.in-video {
    background: transparent;
    backdrop-filter: none;
    box-shadow: none;
    border-bottom: none;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    font-weight: bold;
    font-size: 1.5rem;
    color: var(--text-color);
    transition: all 0.3s ease;
    cursor: pointer;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    letter-spacing: 0.5px;
    font-style: normal;
}

.nav-logo:hover {
    transform: scale(1.05);
    filter: drop-shadow(0 4px 8px rgba(255, 255, 255, 0.1));
}

.nav-logo .logo {
    height: auto;
    max-height: 40px;
    margin-right: 12px;
    object-fit: contain;
}



.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--light-text);
    font-weight: 500;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    padding: 8px 16px;
    border-radius: 8px;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
    letter-spacing: 0.3px;
    font-style: normal;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-color);
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.1) 0%, 
        rgba(255, 255, 255, 0.05) 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(255, 255, 255, 0.1);
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 2px;
    left: 50%;
    background: linear-gradient(90deg, 
        transparent 0%, 
        rgba(255, 255, 255, 0.8) 50%, 
        transparent 100%);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    transform: translateX(-50%);
    border-radius: 2px;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* 移动端导航 */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
    padding: 8px;
    border-radius: 6px;
    transition: all 0.3s ease;
}

.hamburger:hover {
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.1) 0%, 
        rgba(255, 255, 255, 0.05) 100%);
    transform: scale(1.1);
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: linear-gradient(90deg, 
        rgba(255, 255, 255, 0.8) 0%, 
        rgba(255, 255, 255, 1) 50%, 
        rgba(255, 255, 255, 0.8) 100%);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: 2px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* 主要内容区域 */
main {
    padding-top: 80px;
}

/* 首页横幅 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--primary-color) 100%);
    position: relative;
    overflow: hidden;
}

/* 视频背景 */
.hero-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: 1;
}

/* 视频遮罩层 */
.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 2;
}

.hero-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 3;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 30% 40%, rgba(64, 64, 64, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 70% 80%, rgba(45, 45, 45, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    text-align: center;
    z-index: 4;
    position: relative;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--text-color) 0%, var(--light-text) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 1s ease;
    letter-spacing: 1.2px;
    font-style: normal;
}

/* 首页标题样式 */
.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--text-color) 0%, var(--light-text) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 1s ease;
    letter-spacing: 6px !important;
    font-style: normal;
    font-weight: 700;
}

/* 强制应用字间距 */
h1.hero-title {
    letter-spacing: 6px !important;
}

.hero-content h1.hero-title {
    letter-spacing: 6px !important;
}

.hero p {
    font-size: 1.3rem;
    margin-bottom: 2rem;
    color: var(--light-text);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 1s ease 0.2s both;
    letter-spacing: 0.8px;
}

/* 首页副标题样式 */
.hero-subtitle {
    font-size: 1.4rem;
    margin-bottom: 1.5rem;
    color: var(--light-text);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 1s ease 0.2s both;
    letter-spacing: 1.5px;
    font-style: italic;
    font-weight: 500;
    line-height: 1.8;
}

/* 首页描述样式 */
.hero-description {
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    color: var(--light-text);
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 1s ease 0.3s both;
    letter-spacing: 1px;
    font-style: normal;
    line-height: 1.9;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease 0.4s both;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease 0.4s both;
}

.btn {
    display: inline-block;
    padding: 15px 30px;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    font-size: 1rem;
    letter-spacing: 1px;
    font-style: normal;
}

.btn-primary {
    background: var(--text-color);
    color: var(--bg-color);
    border-color: var(--text-color);
}

.btn-primary:hover {
    background: transparent;
    color: var(--text-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-secondary {
    background: transparent;
    color: var(--text-color);
    border-color: var(--text-color);
}

.btn-secondary:hover {
    background: var(--text-color);
    color: var(--bg-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* 通用区块样式 */
.section {
    padding: 100px 0;
    position: relative;
}

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

.section-title h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.section-title p {
    font-size: 1.2rem;
    color: var(--light-text);
    max-width: 600px;
    margin: 0 auto;
}

/* 关于我们 */
.about {
    background: var(--primary-color);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h3 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.about-text p {
    margin-bottom: 1.5rem;
    color: var(--light-text);
    font-size: 1.1rem;
}

/* 信息卡片布局（用于服务与优势） */
.advantages,
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.advantages {
    grid-template-columns: repeat(2, minmax(280px, 1fr));
}

.info-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
}

.info-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.info-card .card-media {
    background: var(--secondary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    color: var(--text-color);
    font-size: 3rem;
    border-bottom: 1px solid var(--border-color);
}

.info-card .card-content {
    padding: 2rem;
}

.info-card .card-content h3,
.info-card .card-content h4 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.info-card .card-content p {
    color: var(--light-text);
    line-height: 1.6;
}

.service-features {
    list-style: none;
}

.service-features li {
    padding: 0.5rem 0;
    color: var(--light-text);
    position: relative;
    padding-left: 1.5rem;
}

.service-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--text-color);
    font-weight: bold;
}

/* 项目案例 */
.projects {
    background: var(--primary-color);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.project-image {
    width: 100%;
    height: 200px;
    background: var(--secondary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--light-text);
    font-size: 1.2rem;
}

.project-content {
    padding: 2rem;
}

.project-content h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.project-content p {
    color: var(--light-text);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.project-tag {
    background: var(--secondary-color);
    color: var(--light-text);
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    font-size: 0.9rem;
    border: 1px solid var(--border-color);
}

/* 视频播放器样式 */
.video-container {
    position: relative;
    width: 100%;
    height: 100%;
    overflow: hidden;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
}

.project-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.project-video:hover {
    transform: scale(1.05);
}

.video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        rgba(0, 0, 0, 0.3) 0%,
        rgba(0, 0, 0, 0.1) 50%,
        rgba(0, 0, 0, 0.3) 100%
    );
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 1;
    transition: opacity 0.3s ease;
    cursor: pointer;
}

.play-btn {
    background: rgba(255, 255, 255, 0.9);
    border: none;
    border-radius: 50%;
    width: 70px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
}

.play-btn:hover {
    background: rgba(255, 255, 255, 1);
    transform: scale(1.1);
    box-shadow: 0 6px 25px rgba(0, 0, 0, 0.4);
}

.play-btn i {
    font-size: 1.5rem;
    color: var(--bg-color);
    margin-left: 3px; /* 微调播放图标位置 */
}

.play-btn i.fa-pause {
    margin-left: 0; /* 暂停图标居中 */
}

/* 视频加载状态 */
.video-container::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 40px;
    height: 40px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top: 3px solid white;
    border-radius: 50%;
    animation: video-loading 1s linear infinite;
    z-index: 1;
    opacity: 0;
}

.video-container.loading::before {
    opacity: 1;
}

@keyframes video-loading {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}

/* 项目详情页面样式 */
.project-detail {
    padding: 120px 0 80px;
    background: var(--bg-color);
    min-height: 100vh;
}

.back-button {
    margin-bottom: 2rem;
}

.project-header {
    text-align: center;
    margin-bottom: 4rem;
    padding: 2rem 0;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.project-header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--text-color);
    background: linear-gradient(135deg, var(--text-color) 0%, var(--light-text) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.project-subtitle {
    font-size: 1.3rem;
    color: var(--light-text);
    margin-bottom: 2rem;
    font-style: italic;
}

.project-meta {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.project-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--light-text);
    font-size: 1rem;
}

.project-meta i {
    color: var(--text-color);
}

/* 项目视频展示区 */
.project-videos {
    margin-bottom: 4rem;
}

.project-videos h2 {
    font-size: 2.2rem;
    margin-bottom: 2rem;
    color: var(--text-color);
    text-align: center;
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.video-item {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.video-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.video-item .video-container {
    height: 250px;
}

.video-item h3 {
    padding: 1.5rem 1.5rem 1rem;
    font-size: 1.3rem;
    color: var(--text-color);
    margin: 0;
}

.video-item p {
    padding: 0 1.5rem 1.5rem;
    color: var(--light-text);
    line-height: 1.6;
    margin: 0;
}

.detail-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 项目信息区域 */
.project-info {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-bottom: 4rem;
}

.project-description {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.project-description h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.project-description h3 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: var(--text-color);
}

.project-description p {
    color: var(--light-text);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    padding: 0.8rem 0;
    color: var(--light-text);
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.feature-list li:last-child {
    border-bottom: none;
}

.feature-list i {
    color: var(--text-color);
    margin-top: 0.2rem;
    min-width: 20px;
}

.feature-list strong {
    color: var(--text-color);
}

/* 项目统计 */
.project-stats {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.project-stats h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--text-color);
    text-align: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.stat-item {
    text-align: center;
    padding: 1.5rem;
    background: var(--secondary-color);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.stat-number {
    font-size: 2rem;
    font-weight: bold;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--light-text);
}

/* 技术栈 */
.tech-stack {
    margin-bottom: 4rem;
}

.tech-stack h2 {
    font-size: 2.2rem;
    margin-bottom: 2rem;
    color: var(--text-color);
    text-align: center;
}

.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
}

.tech-tag {
    background: var(--card-bg);
    color: var(--text-color);
    padding: 0.8rem 1.5rem;
    border-radius: 25px;
    font-size: 0.95rem;
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
    font-weight: 500;
}

.tech-tag:hover {
    background: var(--text-color);
    color: var(--bg-color);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

/* 相关项目 */
.related-projects h2 {
    font-size: 2.2rem;
    margin-bottom: 2rem;
    color: var(--text-color);
    text-align: center;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.related-item {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    color: inherit;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    text-align: center;
}

.related-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.related-image {
    width: 80px;
    height: 80px;
    background: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    border: 2px solid var(--border-color);
}

.related-image i {
    font-size: 2rem;
    color: var(--text-color);
}

.related-item h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.related-item p {
    color: var(--light-text);
    font-size: 0.95rem;
    line-height: 1.5;
}

/* 联系我们 */
.contact {
    background: var(--bg-color);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info h3 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--text-color);
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.contact-item:hover {
    transform: translateX(5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
}

.contact-item i {
    font-size: 2rem;
    color: var(--text-color);
    margin-right: 1.5rem;
    min-width: 50px;
}

.contact-item div h4 {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.contact-item div p {
    color: var(--light-text);
}

/* 联系表单 */
.contact-form {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.contact-form h3 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    color: var(--text-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-color);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--secondary-color);
    color: var(--text-color);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--text-color);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* 页脚 */
.footer {
    background: var(--primary-color);
    color: var(--light-text);
    text-align: center;
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
}

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

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* 章节标题优化 */
.section-title {
    letter-spacing: 1.2px;
    font-style: normal;
}

.section-subtitle {
    letter-spacing: 0.8px;
    font-style: italic;
    opacity: 0.9;
}

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

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 80px;
        flex-direction: column;
        background: rgba(13, 13, 13, 0.98);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.3);
        padding: 2rem 0;
        border-top: 1px solid var(--border-color);
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-menu li {
        margin: 1rem 0;
    }

    .hero-container {
        padding: 0 1rem;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .hero-title {
        font-size: 2.5rem;
        letter-spacing: 4px !important;
    }

    .hero-subtitle {
        font-size: 1.2rem;
        letter-spacing: 1.2px;
    }

    .hero-description {
        font-size: 1.1rem;
        letter-spacing: 0.8px;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    /* 移动端视频背景优化 */
    .hero-video {
        object-position: center center;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .advantages {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    /* 移动端视频播放器优化 */
    .video-container {
        height: 200px;
    }

    .play-btn {
        width: 60px;
        height: 60px;
    }

    .play-btn i {
        font-size: 1.3rem;
    }

    .section {
        padding: 60px 0;
    }

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

    .contact-form {
        padding: 2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-container {
        padding: 0 15px;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero-title {
        font-size: 2rem;
        letter-spacing: 8px !important;
    }

    .hero-subtitle {
        font-size: 1.1rem;
        letter-spacing: 1px;
    }

    .hero-description {
        font-size: 1rem;
        letter-spacing: 0.6px;
    }

    .hero p {
        font-size: 1rem;
    }

    .btn {
        padding: 12px 24px;
        font-size: 0.9rem;
    }

    /* 小屏幕设备视频播放器优化 */
    .video-container {
        height: 180px;
    }

    .play-btn {
        width: 50px;
        height: 50px;
    }

    .play-btn i {
        font-size: 1.1rem;
    }

    .info-card,
    .contact-form {
        padding: 1.5rem;
    }

    .section-title h2 {
        font-size: 1.8rem;
    }

    /* 项目详情页面响应式 */
    .project-header h1 {
        font-size: 2rem;
    }

    .project-info {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

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

    .project-meta {
        flex-direction: column;
        gap: 1rem;
    }

    .related-grid {
        grid-template-columns: 1fr;
    }
    
    .advantages {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
} 

/* 项目分类筛选样式 */
.project-categories {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 3rem;
    padding: 0 1rem;
}

.category-btn {
    background: transparent;
    border: 2px solid #3498db;
    color: #3498db;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
    font-size: 0.9rem;
    white-space: nowrap;
}

.category-btn:hover {
    background: #3498db;
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.3);
}

.category-btn.active {
    background: #3498db;
    color: white;
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.3);
}

/* 项目卡片筛选动画 */
.project-card {
    transition: all 0.5s ease;
    opacity: 1;
    transform: scale(1);
}

.project-card.hidden {
    opacity: 0;
    transform: scale(0.8);
    display: none;
}

/* 响应式分类按钮 */
@media (max-width: 768px) {
    .project-categories {
        gap: 0.5rem;
        margin-bottom: 2rem;
    }
    
    .category-btn {
        padding: 0.5rem 1rem;
        font-size: 0.8rem;
    }
}