/* ============================================
   CSS 变量和基础样式
   ============================================ */

:root {
    /* 颜色系统 */
    --primary: #0F3A7D;
    --primary-dark: #051f3e;
    --accent: #00D9FF;
    --accent-dark: #00a8cc;
    --background: #0a0e27;
    --background-light: #1a1a2e;
    --foreground: #f5f7fa;
    --foreground-dark: #b8bcc4;
    --border: #2a2a3e;
    --card-bg: #151a2f;
    
    /* 字体 */
    --font-display: 'Playfair Display', serif;
    --font-sans: 'Poppins', sans-serif;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.2);
    --shadow-accent: 0 0 20px rgba(0, 217, 255, 0.2);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--background);
    color: var(--foreground);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ============================================
   容器和布局
   ============================================ */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ============================================
   导航栏
   ============================================ */

.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(10, 14, 39, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    padding: var(--spacing-md) 0;
}

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

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
    font-weight: bold;
    font-family: var(--font-display);
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: var(--accent);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--background);
}

.navbar-menu {
    display: flex;
    gap: var(--spacing-xl);
}

.nav-link {
    font-size: 0.875rem;
    color: var(--foreground);
    text-decoration: none;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: var(--accent);
}

@media (max-width: 768px) {
    .navbar-menu {
        display: none;
    }
}

/* ============================================
   英雄部分
   ============================================ */

.hero {
    position: relative;
    margin-top: 64px;
    padding: var(--spacing-3xl) 0;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #1a1a2e 0%, #0f3a7d 50%, #1a1a2e 100%);
    background-size: 200% 200%;
    animation: gradientShift 15s ease infinite;
    z-index: 0;
}

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

.hero-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(0, 217, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(15, 58, 125, 0.2) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.hero-title {
    font-family: var(--font-display);
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
    line-height: 1.2;
}

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

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--foreground-dark);
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-bottom: var(--spacing-3xl);
    flex-wrap: wrap;
}

/* ============================================
   按钮
   ============================================ */

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-lg);
    font-family: var(--font-sans);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all 0.3s ease;
    text-decoration: none;
}

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

.btn-primary:hover {
    background: var(--accent-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 217, 255, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--foreground);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    border-color: var(--accent);
    color: var(--accent);
}

/* ============================================
   统计卡片
   ============================================ */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.stat-card {
    background: rgba(21, 26, 47, 0.5);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    transition: all 0.3s ease;
}

.stat-card:hover {
    border-color: var(--accent);
    background: rgba(0, 217, 255, 0.05);
}

.stat-value {
    font-size: 2rem;
    font-weight: 800;
    color: var(--accent);
    margin-bottom: var(--spacing-sm);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--foreground-dark);
}

/* ============================================
   部分标题
   ============================================ */

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-header h2,
.section-title {
    font-family: var(--font-display);
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.section-header p {
    font-size: 1.125rem;
    color: var(--foreground-dark);
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   服务部分
   ============================================ */

.services {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(180deg, transparent 0%, rgba(0, 217, 255, 0.05) 100%);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.service-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    transition: all 0.3s ease;
}

.service-card:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow-accent);
    transform: translateY(-4px);
}

.service-icon {
    width: 48px;
    height: 48px;
    background: rgba(0, 217, 255, 0.1);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent);
    margin-bottom: var(--spacing-md);
    transition: all 0.3s ease;
}

.service-card:hover .service-icon {
    background: rgba(0, 217, 255, 0.2);
}

.service-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.service-card p {
    font-size: 0.875rem;
    color: var(--foreground-dark);
}

/* ============================================
   优势部分
   ============================================ */

.benefits {
    padding: var(--spacing-3xl) 0;
}

.benefits-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.benefits-text h2 {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
}

.benefits-text > p {
    color: var(--foreground-dark);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

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

.benefits-list li {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.benefits-list svg {
    width: 20px;
    height: 20px;
    color: var(--accent);
    flex-shrink: 0;
    margin-top: 2px;
}

.benefits-list span {
    color: var(--foreground);
}

.benefits-image {
    position: relative;
}

.benefits-image img {
    width: 100%;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.benefits-image::after {
    content: '';
    position: absolute;
    bottom: -20px;
    right: -20px;
    width: 100px;
    height: 100px;
    background: rgba(0, 217, 255, 0.1);
    border-radius: 50%;
    filter: blur(40px);
}

@media (max-width: 768px) {
    .benefits-content {
        grid-template-columns: 1fr;
    }
    
    .benefits-text h2 {
        font-size: 1.75rem;
    }
}

/* ============================================
   对比部分
   ============================================ */

.comparison {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(180deg, rgba(0, 217, 255, 0.05) 0%, transparent 100%);
}

.table-wrapper {
    overflow-x: auto;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
}

.comparison-table thead {
    border-bottom: 2px solid var(--border);
}

.comparison-table th {
    padding: var(--spacing-lg);
    text-align: left;
    font-weight: 700;
}

.comparison-table td {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border);
}

.comparison-table tbody tr:hover {
    background: rgba(0, 217, 255, 0.05);
}

.comparison-table tbody tr:last-child td {
    border-bottom: none;
}

.comparison-table th:nth-child(3),
.comparison-table td:nth-child(3) {
    color: var(--accent);
}

/* ============================================
   案例部分
   ============================================ */

.cases {
    padding: var(--spacing-3xl) 0;
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.case-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    transition: all 0.3s ease;
}

.case-card:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow-accent);
}

.case-icon {
    width: 40px;
    height: 40px;
    background: rgba(0, 217, 255, 0.1);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent);
    margin-bottom: var(--spacing-md);
}

.case-card h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--foreground-dark);
    margin-bottom: var(--spacing-sm);
}

.case-result {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: var(--spacing-sm);
}

.case-detail {
    font-size: 0.875rem;
    color: var(--foreground-dark);
    line-height: 1.6;
}

/* ============================================
   CTA 部分
   ============================================ */

.cta {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(135deg, rgba(0, 217, 255, 0.1) 0%, rgba(15, 58, 125, 0.1) 100%);
    border-top: 1px solid var(--border);
    text-align: center;
}

.cta h2 {
    font-family: var(--font-display);
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.cta > p {
    font-size: 1.125rem;
    color: var(--foreground-dark);
    margin-bottom: var(--spacing-xl);
}

.cta-form {
    max-width: 500px;
    margin: 0 auto;
}

.form-group {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.form-group input {
    flex: 1;
    min-width: 200px;
    padding: 0.75rem 1rem;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    color: var(--foreground);
    font-family: var(--font-sans);
    transition: all 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0, 217, 255, 0.1);
}

.form-group input::placeholder {
    color: var(--foreground-dark);
}

.form-message {
    margin-top: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--accent);
    min-height: 20px;
}

/* ============================================
   页脚
   ============================================ */

.footer {
    border-top: 1px solid var(--border);
    background: linear-gradient(180deg, transparent 0%, rgba(0, 217, 255, 0.05) 100%);
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: bold;
    font-family: var(--font-display);
    margin-bottom: var(--spacing-md);
}

.footer-section p {
    font-size: 0.875rem;
    color: var(--foreground-dark);
    line-height: 1.6;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: var(--spacing-sm);
}

.footer-section a {
    font-size: 0.875rem;
    color: var(--foreground-dark);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--accent);
}

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-lg);
}

.footer-bottom p {
    font-size: 0.875rem;
    color: var(--foreground-dark);
}

.footer-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-links a {
    font-size: 0.875rem;
    color: var(--foreground-dark);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

/* ============================================
   响应式设计
   ============================================ */

@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .hero {
        padding: var(--spacing-2xl) 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .cases-grid {
        grid-template-columns: 1fr;
    }
    
    .form-group {
        flex-direction: column;
    }
    
    .form-group input,
    .form-group button {
        width: 100%;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.5rem;
    }
    
    .section-header h2,
    .section-title {
        font-size: 1.5rem;
    }
    
    .btn {
        padding: 0.625rem 1.25rem;
        font-size: 0.875rem;
    }
    
    .navbar-brand {
        font-size: 1rem;
    }
}

/* ============================================
   动画
   ============================================ */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.service-card,
.case-card,
.stat-card {
    animation: fadeInUp 0.6s ease-out forwards;
    opacity: 0;
}

.service-card:nth-child(1) { animation-delay: 0.1s; }
.service-card:nth-child(2) { animation-delay: 0.2s; }
.service-card:nth-child(3) { animation-delay: 0.3s; }
.service-card:nth-child(4) { animation-delay: 0.4s; }

.case-card:nth-child(1) { animation-delay: 0.1s; }
.case-card:nth-child(2) { animation-delay: 0.2s; }
.case-card:nth-child(3) { animation-delay: 0.3s; }

.stat-card:nth-child(1) { animation-delay: 0.1s; }
.stat-card:nth-child(2) { animation-delay: 0.2s; }
.stat-card:nth-child(3) { animation-delay: 0.3s; }