/* common.css - 公共样式 */
:root {
    --primary: #0f172a;
    --secondary: #0ea5e9;
    --accent: #8b5cf6;
    --light: #f8fafc;
    --dark: #020617;
    --gray: #94a3b8;
    --success: #10b981;
    --ai-blue: #0284c7;
    --ai-purple: #7e22ce;
    --ai-cyan: #06b6d4;
    --gradient: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #020617 100%);
    --gradient-tech: linear-gradient(135deg, #0f172a 0%, #0284c7 25%, #06b6d4 50%, #7e22ce 75%, #020617 100%);
    --gradient-light: linear-gradient(135deg, #0ea5e9 0%, #06b6d4 100%);
    --gradient-warm: linear-gradient(45deg, #ff9a9e 0%, #fad0c4 100%);
    --gradient-cool: linear-gradient(45deg, #a1c4fd 0%, #c2e9fb 100%);
    --gradient-city: linear-gradient(135deg, #00c9ff 0%, #92fe9d 100%);
    --gradient-ai: linear-gradient(45deg, #0284c7 0%, #06b6d4 25%, #8b5cf6 50%, #0ea5e9 75%, #7e22ce 100%);
    --ai-glow: 0 0 15px rgba(2, 132, 199, 0.5), 0 0 30px rgba(126, 34, 206, 0.3);
}

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

body {
    font-family: 'Exo 2', sans-serif;
    color: var(--light);
    background: var(--gradient-tech);
    background-attachment: fixed;
    overflow-x: hidden;
    line-height: 1.6;
}

h1, h2, h3, h4, h5 {
    font-family: 'Orbitron', sans-serif;
    font-weight: 600;
    margin-bottom: 1rem;
}

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

/* 动画效果 */
@keyframes pulse {
    0%, 100% { 
        transform: scale(1); 
        opacity: 0.3; 
    }
    50% { 
        transform: scale(1.2); 
        opacity: 0.6; 
    }
}

@keyframes float {
    0%, 100% { 
        transform: translateY(0); 
    }
    50% { 
        transform: translateY(-20px); 
    }
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slideOut {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(100%);
        opacity: 0;
    }
}

@keyframes highlightFade {
    0% { 
        background-color: rgba(0, 217, 255, 0.3); 
    }
    100% { 
        background-color: transparent; 
    }
}

.floating-element {
    position: absolute;
    width: 20px;
    height: 20px;
    background: rgba(0, 217, 255, 0.3);
    border-radius: 50%;
    z-index: 1;
    animation: float 6s infinite ease-in-out;
}

/* 按钮样式 */
.cta-button {
    display: inline-block;
    background: var(--gradient-ai);
    color: white;
    padding: 15px 40px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s;
    box-shadow: var(--ai-glow);
    border: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.cta-button: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: 0.5s;
    z-index: -1;
}

.cta-button:hover:before {
    left: 100%;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(123, 97, 255, 0.6);
}

.cta-button:active {
    transform: translateY(-1px);
}

/* 通用卡片样式 */
.definition-box {
    background: rgba(30, 41, 59, 0.85);
    border-radius: 15px;
    padding: 40px;
    margin-bottom: 40px;
    border: 1px solid rgba(14, 165, 233, 0.5);
    backdrop-filter: blur(10px);
    transition: transform 0.3s, box-shadow 0.3s;
    box-shadow: 0 8px 32px rgba(2, 6, 23, 0.5);
    position: relative;
    overflow: hidden;
}



.definition-box:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.definition-box h3 {
    color: #00d9ff;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    text-shadow: 0 0 10px rgba(0, 217, 255, 0.5);
}

.definition-box h3 i {
    margin-right: 10px;
    color: #00d9ff;
    text-shadow: 0 0 10px rgba(0, 217, 255, 0.5);
}

.definition-box p {
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
}

.definition-box ul {
    padding-left: 20px;
    margin-top: 15px;
}

.definition-box li {
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 10px;
    line-height: 1.7;
    position: relative;
}

.definition-box li:before {
    content: '•';
    color: #00d9ff;
    font-weight: bold;
    display: inline-block;
    width: 1em;
    margin-left: -1em;
    text-shadow: 0 0 5px rgba(0, 217, 255, 0.5);
}

/* 章节标题样式 */
.section {
    padding: 80px 0;
    position: relative;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
    position: relative;
}

.section-title h2 {
    font-size: 2.5rem;
    display: inline-block;
    position: relative;
    padding-bottom: 15px;
}

.section-title h2:after {
    content: '';
    position: absolute;
    width: 80px;
    height: 4px;
    background: var(--gradient-light);
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
}

/* 通用网格布局 */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

/* 页眉样式 */
header {
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
    border-bottom: 1px solid rgba(14, 165, 233, 0.3);
    transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(2, 6, 23, 0.5);
}

.header-scrolled {
    padding: 10px 0;
    background: rgba(15, 23, 42, 0.98);
    box-shadow: 0 4px 25px rgba(2, 6, 23, 0.7);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative; /* 为移动端菜单提供定位上下文 */
}

/* Logo样式 */
.logo {
    font-family: 'Orbitron', sans-serif;
    font-size: 1.8rem;
    font-weight: 700;
    background: var(--gradient-light);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: flex;
    align-items: center;
    text-decoration: none;
}
.logo a {
    display: flex;
    align-items: center;
}

.logo-img {
    height: 40px;
    width: auto;
}

/* 导航链接样式 */
.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    color: var(--light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

.nav-links a:hover {
    color: var(--secondary);
}

.nav-links a:after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background: var(--secondary);
    bottom: -5px;
    left: 0;
    transition: width 0.3s;
}

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

.nav-links a.active {
    color: var(--secondary);
}

.nav-links a.active:after {
    content: '';
    position: absolute;
    width: 100%;
    height: 2px;
    background: var(--secondary);
    bottom: -5px;
    left: 0;
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--light);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 5px;
    transition: color 0.3s;
}

.mobile-menu-btn:hover {
    color: var(--secondary);
}

/* 页脚样式 */
footer {
    background: linear-gradient(135deg, #0f172a, #1e293b);
    padding: 60px 0 30px;
    border-top: 1px solid rgba(14, 165, 233, 0.2);
    box-shadow: 0 -4px 20px rgba(2, 6, 23, 0.3);
}

.footer-content {
    text-align: center;
}

.footer-logo {
    font-family: 'Orbitron', sans-serif;
    font-size: 2.2rem;
    font-weight: 700;
    background: var(--gradient-light);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 15px;
}

.footer-tagline {
    color: rgba(255, 255, 255, 0.8);
    max-width: 700px;
    margin: 0 auto 40px;
    font-size: 1.1rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
    text-align: left;
}

.footer-column h4 {
    color: var(--secondary);
    margin-bottom: 20px;
    font-size: 1.2rem;
    border-bottom: 2px solid rgba(0, 217, 255, 0.3);
    padding-bottom: 10px;
}

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

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

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

.footer-column ul li a:hover {
    color: var(--secondary);
}

.footer-column ul li i {
    margin-right: 10px;
    color: var(--secondary);
    width: 20px;
}

.footer-social {
    margin: 40px 0;
}

.social-icon {
    display: inline-block;
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    margin: 0 10px;
    color: white;
    font-size: 1.2rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
    text-decoration: none;
}

.social-icon:hover {
    background: var(--gradient-light);
    transform: translateY(-5px);
}

.copyright {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

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

.copyright a:hover {
    color: var(--secondary);
}

/* 联系信息样式 */
.contact {
    padding: 80px 0;
    background: var(--gradient-ai);
    text-align: center;
    position: relative;
    overflow: hidden;
    background-size: 400% 400%;
    animation: gradientAnimation 15s ease infinite;
}

.contact:before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at center, transparent 30%, rgba(0, 0, 0, 0.2) 100%);
    pointer-events: none;
}

.contact h2 {
    color: white;
    background: none;
    -webkit-background-clip: initial;
    background-clip: initial;
    position: relative;
    z-index: 2;
    font-size: 2.5rem;
    margin-bottom: 20px;
    text-align: center;
}

.contact p {
    color: rgba(255, 255, 255, 0.9);
    background: none;
    -webkit-background-clip: initial;
    background-clip: initial;
    position: relative;
    z-index: 2;
    font-size: 1.2rem;
    margin-bottom: 30px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.contact-info {
    margin-top: 30px;
}

.contact-item {
    display: inline-flex;
    align-items: center;
    margin: 0 20px 20px;
    font-size: 1.1rem;
    position: relative;
    z-index: 2;
}

.contact-item i {
    margin-right: 10px;
    font-size: 1.3rem;
    background: linear-gradient(135deg, #00d9ff, #7b61ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    transition: all 0.3s;
}

.contact-item a {
    text-decoration: none;
    transition: color 0.3s;
    background: linear-gradient(135deg, #ffffff, #00d9ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.contact-item a:hover {
    background: linear-gradient(135deg, #00d9ff, #7b61ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

/* 北京相关项目特殊样式 */
.beijing-related {
    position: relative;
    display: inline-block;
}

.beijing-related:after {
    display: none;
}

@keyframes shine {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

/* 北京主题背景渐变 */
.beijing-bg-gradient {
    background: linear-gradient(135deg, #0066cc, #3399ff, #00ccff, #00d9ff);
    background-size: 400% 400%;
    animation: gradientFlow 8s ease infinite;
}

@keyframes gradientFlow {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* 北京元素特殊动画 */
.beijing-element {
    animation: beijingPulse 2s ease-in-out infinite alternate;
}

@keyframes beijingPulse {
    from {
        box-shadow: 0 0 10px rgba(0, 102, 204, 0.3);
    }
    to {
        box-shadow: 0 0 20px rgba(0, 204, 255, 0.6), 0 0 30px rgba(51, 153, 255, 0.4);
    }
}

/* AI平台标签样式 */
.ai-platform {
    background: rgba(255, 255, 255, 0.2);
    padding: 10px 20px;
    border-radius: 50px;
    font-weight: 500;
    backdrop-filter: blur(5px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    transition: all 0.3s;
}

.ai-platform:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-3px);
}

.ai-platforms-mini {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 15px;
}

.platform-tag {
    background: rgba(0, 217, 255, 0.2);
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    color: var(--secondary);
}

/* 响应式设计 */
@media (max-width: 992px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: rgba(5, 12, 26, 0.98);
        flex-direction: column;
        padding: 20px;
        box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
        z-index: 1001; /* 确保菜单显示在其他元素之上 */
        margin-top: 15px; /* 避免与header边界重叠 */
    }
    
    .nav-links.active {
        display: flex;
        z-index: 1001; /* 确保激活状态下菜单在最前面 */
    }
    
    .nav-links li {
        margin: 10px 0;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .section-title h2 {
        font-size: 2.2rem;
    }
    
    .grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .section-title h2 {
        font-size: 2rem;
    }
    
    .contact-item {
        display: block;
        margin-bottom: 15px;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-column h4 {
        text-align: center;
    }
}

@media (max-width: 480px) {
    .section {
        padding: 60px 0;
    }
    
    .section-title h2 {
        font-size: 1.8rem;
    }
    
    .definition-box {
        padding: 25px;
    }
    
    .cta-button {
        padding: 12px 30px;
        font-size: 1rem;
    }
    
    .logo {
        font-size: 1.5rem;
    }
    
    .logo i {
        font-size: 1.5rem;
    }
}

/* 工具类 */
.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

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

.mt-20 { margin-top: 20px; }
.mt-30 { margin-top: 30px; }
.mt-40 { margin-top: 40px; }
.mb-20 { margin-bottom: 20px; }
.mb-30 { margin-bottom: 30px; }
.mb-40 { margin-bottom: 40px; }
.ml-20 { margin-left: 20px; }
.mr-20 { margin-right: 20px; }

.p-20 { padding: 20px; }
.p-30 { padding: 30px; }
.p-40 { padding: 40px; }

.d-flex {
    display: flex;
}

.align-center {
    align-items: center;
}

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

.justify-between {
    justify-content: space-between;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-column {
    flex-direction: column;
}

.w-100 {
    width: 100%;
}

.h-100 {
    height: 100%;
}

.relative {
    position: relative;
}

.absolute {
    position: absolute;
}

.sticky {
    position: sticky;
}

.z-1 { z-index: 1; }
.z-10 { z-index: 10; }
.z-100 { z-index: 100; }
.z-1000 { z-index: 1000; }

.overflow-hidden {
    overflow: hidden;
}

.rounded {
    border-radius: 8px;
}

.rounded-lg {
    border-radius: 15px;
}

.rounded-full {
    border-radius: 50%;
}

.shadow {
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.shadow-lg {
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.shadow-xl {
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

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

.bg-secondary {
    background-color: var(--secondary);
}

.bg-accent {
    background-color: var(--accent);
}

.bg-light {
    background-color: var(--light);
}

.bg-dark {
    background-color: var(--dark);
}

.bg-gradient {
    background: var(--gradient);
}

.bg-gradient-light {
    background: var(--gradient-light);
}

.text-primary {
    color: var(--primary);
}

.text-secondary {
    color: var(--secondary);
}

.text-accent {
    color: var(--accent);
}

.text-light {
    color: var(--light);
}

.text-dark {
    color: var(--dark);
}

.text-gray {
    color: var(--gray);
}

.text-success {
    color: var(--success);
}

.font-exo {
    font-family: 'Exo 2', sans-serif;
}

.font-orbitron {
    font-family: 'Orbitron', sans-serif;
}

.font-bold {
    font-weight: 700;
}

.font-semibold {
    font-weight: 600;
}

.font-medium {
    font-weight: 500;
}

.font-normal {
    font-weight: 400;
}

.text-xs { font-size: 0.75rem; }
.text-sm { font-size: 0.875rem; }
.text-base { font-size: 1rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }
.text-2xl { font-size: 1.5rem; }
.text-3xl { font-size: 1.875rem; }
.text-4xl { font-size: 2.25rem; }
.text-5xl { font-size: 3rem; }

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--secondary);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 面包屑导航 */
.breadcrumb-section {
    background: rgba(5, 12, 26, 0.9);
    padding: 20px 0;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 10px;
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

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

.breadcrumb a:hover {
    color: var(--secondary);
}

.breadcrumb .current {
    color: var(--secondary);
    font-weight: 500;
}

.breadcrumb i {
    font-size: 0.8rem;
}

/* 表单元素 */
.form-group {
    margin-bottom: 20px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 15px;
    background: rgba(30, 41, 59, 0.5);
    border: 1px solid rgba(14, 165, 233, 0.4);
    border-radius: 8px;
    color: white;
    font-family: 'Exo 2', sans-serif;
    font-size: 1rem;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--secondary);
    box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.2);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--secondary);
}

/* 消息提示 */
.message-alert {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 30px;
    border-radius: 8px;
    z-index: 10000;
    animation: slideIn 0.3s ease;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    max-width: 300px;
    color: white;
}

.message-success {
    background: var(--success);
}

.message-error {
    background: #ff6b6b;
}

.message-info {
    background: var(--secondary);
}

.message-warning {
    background: #f59e0b;
}