/* ===================================
   北京众企云天科技有限公司 - 企业网站样式
   风格：黑色为主，蓝白为辅（科技风）
   =================================== */

/* CSS变量 */
:root {
    --primary-color: #0066ff;      /* 蓝色主色 */
    --primary-dark: #0052cc;      /* 深蓝色 */
    --primary-light: #3385ff;     /* 浅蓝色 */
    --accent-color: #00d4ff;      /* 青色点缀 */
    --bg-dark: #0a0a0a;           /* 深黑背景 */
    --bg-dark-secondary: #141414; /* 次级黑背景 */
    --bg-dark-tertiary: #1a1a1a;  /* 三级黑背景 */
    --text-white: #ffffff;        /* 白色文字 */
    --text-gray: #b0b0b0;         /* 灰色文字 */
    --text-dark-gray: #666666;    /* 深灰文字 */
    --border-color: #2a2a2a;      /* 边框颜色 */
    --gradient-primary: linear-gradient(135deg, #0066ff 0%, #00d4ff 100%);
}

/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-white);
    line-height: 1.6;
    overflow-x: hidden;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* ===================================
   导航栏
   =================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.logo-text {
    font-size: 24px;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    gap: 40px;
}

.nav-menu a {
    color: var(--text-gray);
    font-size: 15px;
    font-weight: 500;
    position: relative;
    padding: 5px 0;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--text-white);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s ease;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-white);
    transition: all 0.3s ease;
}

/* ===================================
   首屏Hero
   =================================== */
.hero {
    position: relative;
    height: 100vh;
    min-height: 700px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: var(--bg-dark);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(ellipse at 20% 50%, rgba(0, 102, 255, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 50%, rgba(0, 212, 255, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 100%, rgba(0, 102, 255, 0.1) 0%, transparent 40%);
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.03)" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: 0 20px;
    max-width: 900px;
}

.hero h1 {
    font-size: 56px;
    font-weight: 700;
    margin-bottom: 20px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.8s ease;
}

.hero .tagline {
    font-size: 22px;
    color: var(--accent-color);
    margin-bottom: 25px;
    font-weight: 500;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero .desc {
    font-size: 18px;
    color: var(--text-gray);
    margin-bottom: 40px;
    line-height: 1.8;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.hero .btn {
    display: inline-block;
    padding: 15px 40px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    transition: all 0.3s ease;
    animation: fadeInUp 0.8s ease 0.6s both;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--text-white);
    box-shadow: 0 4px 20px rgba(0, 102, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 30px rgba(0, 102, 255, 0.5);
}

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

/* ===================================
   通用标题
   =================================== */
.section-title {
    font-size: 36px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

/* ===================================
   核心优势
   =================================== */
.features {
    padding: 100px 0;
    background: var(--bg-dark-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.feature-card {
    background: var(--bg-dark-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 40px 30px;
    text-align: center;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    border-color: var(--primary-color);
    box-shadow: 0 10px 40px rgba(0, 102, 255, 0.15);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--text-white);
}

.feature-card p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.7;
}

/* ===================================
   业务领域
   =================================== */
.business {
    padding: 100px 0;
    background: var(--bg-dark);
}

.business-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.business-item {
    background: var(--bg-dark-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 40px 25px;
    text-align: center;
    transition: all 0.3s ease;
}

.business-item:hover {
    transform: translateY(-8px);
    border-color: var(--primary-light);
}

.business-icon {
    font-size: 42px;
    margin-bottom: 20px;
}

.business-item h3 {
    font-size: 18px;
    margin-bottom: 15px;
    color: var(--text-white);
}

.business-item p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.6;
}

/* ===================================
   页面头部
   =================================== */
.page-header {
    padding: 180px 0 80px;
    background: var(--bg-dark);
    text-align: center;
    position: relative;
}

.page-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(ellipse at 50% 0%, rgba(0, 102, 255, 0.1) 0%, transparent 60%);
}

.page-header h1 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 15px;
    position: relative;
}

.page-header p {
    font-size: 20px;
    color: var(--text-gray);
    position: relative;
}

/* ===================================
   关于我们
   =================================== */
.about-intro {
    padding: 80px 0;
    background: var(--bg-dark-secondary);
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-content h2 {
    font-size: 32px;
    margin-bottom: 30px;
    color: var(--text-white);
}

.about-content .lead {
    font-size: 20px;
    color: var(--accent-color);
    margin-bottom: 25px;
    font-weight: 500;
}

.about-content p {
    color: var(--text-gray);
    margin-bottom: 20px;
    line-height: 1.8;
    font-size: 16px;
}

/* 企业文化 */
.about-culture {
    padding: 80px 0;
    background: var(--bg-dark);
}

.culture-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.culture-item {
    text-align: center;
    padding: 40px 30px;
    background: var(--bg-dark-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
}

.culture-num {
    font-size: 48px;
    font-weight: 700;
    color: var(--primary-color);
    opacity: 0.5;
    margin-bottom: 20px;
}

.culture-item h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: var(--text-white);
}

.culture-item p {
    color: var(--text-gray);
    font-size: 15px;
    line-height: 1.7;
}

/* 团队实力 */
.about-team {
    padding: 80px 0;
    background: var(--bg-dark-secondary);
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.team-card {
    background: var(--bg-dark-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 40px 20px;
    text-align: center;
    transition: all 0.3s ease;
}

.team-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-5px);
}

.team-icon {
    font-size: 42px;
    margin-bottom: 20px;
}

.team-card h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: var(--text-white);
}

.team-card p {
    color: var(--text-gray);
    font-size: 14px;
}

/* ===================================
   业务介绍
   =================================== */
.services-main {
    padding: 80px 0;
    background: var(--bg-dark);
}

.service-item {
    display: flex;
    align-items: center;
    gap: 60px;
    padding: 60px 0;
    border-bottom: 1px solid var(--border-color);
}

.service-item:last-child {
    border-bottom: none;
}

.service-item.reverse {
    flex-direction: row-reverse;
}

.service-content {
    flex: 1;
}

.service-content h2 {
    font-size: 32px;
    margin-bottom: 20px;
    color: var(--text-white);
}

.service-lead {
    font-size: 18px;
    color: var(--accent-color);
    margin-bottom: 25px;
    font-weight: 500;
}

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

.service-list li {
    color: var(--text-gray);
    margin-bottom: 15px;
    padding-left: 20px;
    position: relative;
    line-height: 1.6;
}

.service-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

.service-visual {
    font-size: 80px;
    flex-shrink: 0;
}

/* 行业解决方案 */
.solutions {
    padding: 80px 0;
    background: var(--bg-dark-secondary);
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.solution-card {
    background: var(--bg-dark-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 35px 25px;
    text-align: center;
    transition: all 0.3s ease;
}

.solution-card:hover {
    border-color: var(--primary-light);
    transform: translateY(-5px);
}

.solution-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--text-white);
}

.solution-card p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.6;
}

/* ===================================
   联系我们
   =================================== */
.contact-info {
    padding: 80px 0;
    background: var(--bg-dark);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.contact-card {
    background: var(--bg-dark-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 40px 20px;
    text-align: center;
    transition: all 0.3s ease;
}

.contact-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-5px);
}

.contact-icon {
    font-size: 42px;
    margin-bottom: 20px;
}

.contact-card h3 {
    font-size: 18px;
    margin-bottom: 15px;
    color: var(--text-white);
}

.contact-card p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.6;
}

/* 地图 */
.contact-map {
    padding: 0 0 80px;
    background: var(--bg-dark);
}

.map-container {
    background: var(--bg-dark-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 60px;
    text-align: center;
}

.map-placeholder {
    font-size: 18px;
    color: var(--text-white);
}

.map-note {
    color: var(--text-gray) !important;
    margin-top: 10px;
    font-size: 14px !important;
}

/* 交通指南 */
.contact-guide {
    padding: 80px 0;
    background: var(--bg-dark-secondary);
}

.guide-content {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.guide-item {
    padding: 30px;
    background: var(--bg-dark-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
}

.guide-item h3 {
    font-size: 18px;
    margin-bottom: 15px;
    color: var(--primary-light);
}

.guide-item p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.6;
}

/* 在线联系 */
.contact-online {
    padding: 80px 0;
    background: var(--bg-dark);
}

.online-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.online-content > p {
    font-size: 18px;
    color: var(--text-gray);
    margin-bottom: 40px;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 30px;
}

.method-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    padding: 20px;
    background: var(--bg-dark-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 16px;
    color: var(--text-white);
}

.method-icon {
    font-size: 24px;
}

.contact-note {
    color: var(--text-gray) !important;
    font-size: 14px !important;
}

/* ===================================
   页脚
   =================================== */
.footer {
    background: var(--bg-dark-secondary);
    padding: 60px 0 20px;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 18px;
    margin-bottom: 20px;
    color: var(--text-white);
}

.footer-section p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.8;
    margin-bottom: 10px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
}

.footer-bottom p {
    color: var(--text-dark-gray);
    font-size: 13px;
}

/* ===================================
   响应式设计
   =================================== */
@media (max-width: 1024px) {
    .features-grid,
    .business-grid,
    .contact-grid,
    .team-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .culture-grid,
    .solutions-grid,
    .guide-content {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .service-item,
    .service-item.reverse {
        flex-direction: column;
        text-align: center;
    }

    .service-list {
        text-align: left;
    }
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 36px;
    }

    .hero .tagline {
        font-size: 18px;
    }

    .hero .desc {
        font-size: 16px;
    }

    .section-title {
        font-size: 28px;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--bg-dark-secondary);
        flex-direction: column;
        padding: 30px;
        gap: 20px;
        transform: translateY(-150%);
        transition: transform 0.3s ease;
    }

    .nav-menu.active {
        transform: translateY(0);
    }

    .features-grid,
    .business-grid,
    .contact-grid,
    .team-grid {
        grid-template-columns: 1fr;
    }

    .page-header h1 {
        font-size: 36px;
    }

    .service-visual {
        font-size: 60px;
    }
}