/* ==================== 基础样式 ==================== */

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #10b981;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --bg-color: #ffffff;
    --bg-light: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius: 8px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background: var(--bg-color);
}

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

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

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

/* ==================== 按钮样式 ==================== */

.btn {
    display: inline-block;
    padding: 10px 24px;
    font-size: 16px;
    font-weight: 500;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    border: none;
    text-align: center;
}

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

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

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-color);
    color: white;
}

.btn-lg {
    padding: 14px 32px;
    font-size: 18px;
}

.btn-xl {
    padding: 18px 48px;
    font-size: 20px;
}

.btn-block {
    width: 100%;
}

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

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 40px;
}

.logo-text {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    font-size: 16px;
    color: var(--text-color);
    transition: var(--transition);
}

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

/* ==================== 轮播大图 ==================== */

.hero-carousel {
    height: 600px;
    position: relative;
    overflow: hidden;
    margin-top: 70px;
}

.carousel-container {
    height: 100%;
    position: relative;
}

.carousel-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.8s ease, visibility 0.8s ease;
}

.carousel-slide.active {
    opacity: 1;
    visibility: visible;
}

.slide-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.slide-bg a {
    display: block;
    width: 100%;
    height: 100%;
}

.slide-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 1;
}

.slide-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: #fff;
    z-index: 2;
    width: 100%;
    max-width: 800px;
    padding: 0 20px;
}

.slide-content h1 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.slide-content p {
    font-size: 22px;
    margin-bottom: 40px;
    opacity: 0.9;
}

.slide-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.carousel-indicators {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 3;
}

.carousel-indicators span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: background 0.3s;
}

.carousel-indicators span.active,
.carousel-indicators span:hover {
    background: #fff;
}

.carousel-prev,
.carousel-next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    border-radius: 50%;
    color: #fff;
    font-size: 24px;
    cursor: pointer;
    transition: background 0.3s;
    z-index: 3;
}

.carousel-prev {
    left: 40px;
}

.carousel-next {
    right: 40px;
}

.carousel-prev:hover,
.carousel-next:hover {
    background: rgba(255, 255, 255, 0.4);
}

/* ==================== 首屏 ==================== */

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 70px;
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: url('../images/hero-bg.jpg') center/cover no-repeat;
    opacity: 0.2;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    color: white;
}

.hero-title {
    font-size: 48px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 24px;
    opacity: 0.9;
    margin-bottom: 16px;
}

.hero-desc {
    font-size: 18px;
    opacity: 0.8;
    margin-bottom: 32px;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
}

.hero-image {
    display: flex;
    justify-content: center;
}

.placeholder-img {
    width: 500px;
    height: 350px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 24px;
    border: 2px dashed rgba(255, 255, 255, 0.3);
}

/* ==================== 核心优势 ==================== */

.advantages {
    padding: 100px 0;
    background: var(--bg-light);
}

.section-title {
    text-align: center;
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-color);
}

.section-subtitle {
    text-align: center;
    font-size: 18px;
    color: var(--text-light);
    margin-bottom: 48px;
}

.advantage-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.advantage-card {
    background: white;
    padding: 32px 24px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.advantage-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.advantage-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.advantage-number {
    font-size: 42px;
    font-weight: 800;
    color: var(--primary-color);
}

.advantage-label {
    font-size: 18px;
    font-weight: 600;
    margin: 8px 0;
}

.advantage-desc {
    font-size: 14px;
    color: var(--text-light);
}

/* ==================== 功能特性 ==================== */

.features {
    padding: 100px 0;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.feature-card {
    background: white;
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 56px;
    margin-bottom: 20px;
}

.feature-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-color);
}

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

.feature-list li {
    padding: 8px 0;
    padding-left: 24px;
    position: relative;
    color: var(--text-light);
}

.feature-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--secondary-color);
    font-weight: bold;
}

/* ==================== 技术亮点 ==================== */

.tech-highlights {
    padding: 100px 0;
    background: var(--bg-light);
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.tech-item {
    background: white;
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.tech-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.tech-item h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.tech-item p {
    color: var(--text-light);
    margin-bottom: 20px;
}

.tech-compare {
    display: flex;
    gap: 12px;
}

.compare-item {
    flex: 1;
    padding: 12px;
    border-radius: 6px;
    text-align: center;
}

.compare-item.bad {
    background: #fee2e2;
}

.compare-item.good {
    background: #dcfce7;
}

.compare-item .label {
    display: block;
    font-size: 12px;
    color: var(--text-light);
}

.compare-item .value {
    display: block;
    font-size: 18px;
    font-weight: 700;
}

.tech-example {
    background: var(--bg-light);
    padding: 16px;
    border-radius: 6px;
}

.example-item {
    padding: 8px 0;
    font-size: 14px;
}

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

.example-item.highlight {
    background: var(--primary-color);
    color: white;
    margin: 8px -16px -16px;
    padding: 12px 16px;
    border-radius: 0 0 6px 6px;
}

.tech-benefits {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.benefit {
    background: var(--primary-color);
    color: white;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 13px;
}

/* ==================== 解决方案 ==================== */

.solutions {
    padding: 100px 0;
}

.solution-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.solution-card {
    background: white;
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.solution-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.solution-icon {
    font-size: 56px;
    margin-bottom: 16px;
}

.solution-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.solution-card p {
    color: var(--text-light);
    font-size: 15px;
    margin-bottom: 16px;
}

.solution-result {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
}

/* ==================== 数据展示 ==================== */

.stats {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
    text-align: center;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 56px;
    font-weight: 800;
}

.stat-suffix {
    font-size: 24px;
    font-weight: 600;
}

.stat-label {
    font-size: 16px;
    opacity: 0.9;
    margin-top: 8px;
}

/* ==================== 客户案例 ==================== */

.cases {
    padding: 100px 0;
    background: var(--bg-light);
}

.case-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.case-card {
    background: white;
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.case-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.case-logo {
    height: 60px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.placeholder-logo {
    background: var(--bg-light);
    padding: 12px 24px;
    border-radius: 6px;
    font-weight: 600;
    color: var(--text-light);
}

.case-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.case-desc {
    color: var(--text-light);
    margin-bottom: 16px;
}

.case-results {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.case-results span {
    background: var(--bg-light);
    padding: 6px 12px;
    border-radius: 4px;
    font-size: 14px;
    color: var(--primary-color);
}

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

.cta {
    padding: 100px 0;
    text-align: center;
    background: white;
}

.cta h2 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta p {
    font-size: 18px;
    color: var(--text-light);
    margin-bottom: 32px;
}

/* ==================== 联系我们 ==================== */

.contact {
    padding: 100px 0;
    background: var(--bg-light);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-info h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.contact-info > p {
    color: var(--text-light);
    margin-bottom: 32px;
}

.contact-items {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 16px;
}

.contact-icon {
    font-size: 32px;
}

.contact-label {
    font-size: 14px;
    color: var(--text-light);
}

.contact-value {
    font-size: 18px;
    font-weight: 600;
}

.contact-form {
    background: white;
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.contact-form h3 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 24px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    font-size: 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

.footer {
    background: #1f2937;
    color: white;
    padding: 60px 0 30px;
}

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

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand .logo span {
    color: white;
    font-size: 20px;
}

.footer-brand p {
    color: #9ca3af;
}

.footer-links h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-links a {
    color: #9ca3af;
    font-size: 14px;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 20px;
    text-align: center;
    color: #9ca3af;
    font-size: 14px;
}

/* ==================== 返回顶部 ==================== */

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-4px);
}

/* ==================== 响应式 ==================== */

@media (max-width: 1024px) {
    .advantage-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .tech-grid {
        grid-template-columns: 1fr;
    }
    
    .solution-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .navbar .container {
        flex-wrap: wrap;
    }
    
    .nav-links {
        display: none;
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 32px;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-image {
        display: none;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
    
    .advantage-grid {
        grid-template-columns: 1fr;
    }
    
    .solution-grid {
        grid-template-columns: 1fr;
    }
    
    .case-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
}