/*
 * FindAI发现力量 - 企业级AI产品展示网站样式表
 * 现代化企业级AI产品展示网站
 */

/* CSS Variables */
:root {
    --primary-color: #5a67d8;
    --primary-dark: #4c51bf;
    --primary-light: #667eea;
    --secondary-color: #ed8936;
    --text-dark: #1a202c;
    --text-medium: #4a5568;
    --text-light: #718096;
    --bg-light: #f7fafc;
    --bg-white: #ffffff;
    --bg-dark: #1a202c;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 20px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Reset & Base */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-fast);
}

ul {
    list-style: none;
}

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

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-dark);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    color: var(--text-medium);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    font-size: 16px;
    font-weight: 500;
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-align: center;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: white;
    box-shadow: 0 4px 15px rgba(90, 103, 216, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(90, 103, 216, 0.4);
}

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

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

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

.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.btn-lg {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
}

.btn-block {
    width: 100%;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

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

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-dark);
}

.logo-tagline {
    font-size: 12px;
    color: var(--text-light);
}

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

.nav-link {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-medium);
    position: relative;
    padding: 8px 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width var(--transition-normal);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

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

.header-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.contact-info {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-medium);
    font-size: 14px;
}

.phone-icon {
    font-size: 16px;
}

.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: all var(--transition-normal);
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 0 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    z-index: -2;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 30% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
}

.hero-content {
    text-align: center;
    color: white;
    max-width: 800px;
    margin: 0 auto;
    padding: 40px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    color: white;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.hero-subtitle {
    font-size: 2rem;
    font-weight: 600;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 16px;
}

.hero-desc {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 40px;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.hero-actions .btn-outline {
    border-color: white;
    color: white;
}

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

/* Section Styles */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    font-size: 1.125rem;
    color: var(--text-light);
}

.section-header.light .section-title {
    color: white;
}

.section-header.light .section-desc {
    color: rgba(255, 255, 255, 0.8);
}

/* Products Section */
.products-section {
    padding: 100px 0;
    background: var(--bg-light);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.product-card {
    background: white;
    border-radius: var(--radius-lg);
    padding: 40px 30px;
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.product-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.product-card.featured {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: white;
}

.product-card.featured .product-name,
.product-card.featured .product-tagline,
.product-card.featured .product-desc,
.product-card.featured .product-features li {
    color: white;
}

.featured-badge {
    position: absolute;
    top: 20px;
    right: 20px;
    background: var(--secondary-color);
    color: white;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 600;
}

.product-icon {
    margin-bottom: 24px;
}

.product-name {
    font-size: 1.5rem;
    margin-bottom: 8px;
}

.product-tagline {
    font-size: 0.9rem;
    color: var(--primary-color);
    margin-bottom: 16px;
    font-weight: 500;
}

.product-card.featured .product-tagline {
    color: rgba(255, 255, 255, 0.9);
}

.product-desc {
    font-size: 0.95rem;
    margin-bottom: 20px;
    line-height: 1.7;
}

.product-features {
    text-align: left;
    margin-bottom: 24px;
}

.product-features li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 10px;
    color: var(--text-medium);
    font-size: 0.9rem;
}

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

.product-card.featured .product-features li::before {
    color: white;
}

.product-stats {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 24px;
    padding: 20px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.stat-item {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: white;
}

.stat-label {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.8);
}

/* Solutions Section */
.solutions-section {
    padding: 100px 0;
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.solution-card {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    min-height: 400px;
    display: flex;
    align-items: center;
}

.solution-bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    z-index: -1;
}

.solution-card.automotive .solution-bg {
    background: linear-gradient(135deg, #2d3748 0%, #4a5568 100%);
}

.solution-card.retail .solution-bg {
    background: linear-gradient(135deg, #1a365d 0%, #2b6cb0 100%);
}

.solution-bg::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
}

.solution-content {
    position: relative;
    z-index: 1;
    padding: 40px;
    color: white;
}

.solution-icon {
    margin-bottom: 20px;
}

.solution-title {
    font-size: 1.75rem;
    color: white;
    margin-bottom: 12px;
}

.solution-desc {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 20px;
}

.solution-features {
    margin-bottom: 30px;
}

.solution-features li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.85);
}

.solution-features li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: white;
    font-weight: bold;
}

/* Tech Section */
.tech-section {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, #764ba2 100%);
}

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

.tech-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: 30px;
    text-align: center;
    transition: all var(--transition-normal);
}

.tech-card:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-5px);
}

.tech-icon {
    margin-bottom: 20px;
}

.tech-title {
    font-size: 1.25rem;
    color: white;
    margin-bottom: 12px;
}

.tech-desc {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.85);
}

/* Advantages Section */
.advantages-section {
    padding: 100px 0;
    background: var(--bg-light);
}

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

.advantage-card {
    background: white;
    border-radius: var(--radius-lg);
    padding: 40px 30px;
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.advantage-icon {
    margin-bottom: 24px;
}

.advantage-title {
    font-size: 1.25rem;
    margin-bottom: 16px;
}

.advantage-desc {
    font-size: 0.95rem;
    line-height: 1.7;
}

/* Contact Section */
.contact-section {
    padding: 100px 0;
}

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

.contact-info .section-title {
    text-align: left;
}

.contact-desc {
    font-size: 1.125rem;
    margin-bottom: 40px;
}

.contact-details {
    margin-bottom: 40px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 24px;
}

.contact-item .contact-icon {
    font-size: 24px;
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 1rem;
    margin-bottom: 4px;
}

.contact-item p {
    font-size: 0.95rem;
}

.wechat-contact h4 {
    margin-bottom: 16px;
}

.wechat-qr img {
    width: 120px;
    height: 120px;
    border-radius: var(--radius-md);
}

/* Contact Form */
.contact-form-wrapper {
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: 40px;
}

.form-title {
    font-size: 1.5rem;
    margin-bottom: 8px;
}

.form-desc {
    margin-bottom: 24px;
    color: var(--text-light);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-dark);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    font-size: 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: white;
    transition: all var(--transition-fast);
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(90, 103, 216, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

/* Footer */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 80px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand .logo {
    margin-bottom: 20px;
}

.footer-brand .logo-title {
    color: white;
}

.footer-brand .logo-tagline {
    color: rgba(255, 255, 255, 0.6);
}

.footer-desc {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 24px;
    line-height: 1.7;
}

.social-links {
    display: flex;
    gap: 16px;
}

.social-link {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    transition: all var(--transition-normal);
}

.social-link:hover {
    background: var(--primary-color);
}

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

.footer-column h4 {
    font-size: 1rem;
    color: white;
    margin-bottom: 20px;
}

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

.footer-column ul li a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    transition: color var(--transition-fast);
}

.footer-column ul li a:hover {
    color: white;
}

.footer-contact .contact-item {
    flex-direction: column;
    gap: 8px;
}

.footer-contact .contact-item .contact-icon {
    font-size: 16px;
}

.footer-contact .contact-item span {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 8px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .products-grid,
    .tech-grid,
    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .contact-wrapper {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .header-content {
        height: 70px;
    }
    
    .nav-menu {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        box-shadow: var(--shadow-md);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .header-actions {
        display: none;
    }
    
    .mobile-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.5rem;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .products-grid,
    .solutions-grid,
    .tech-grid,
    .advantages-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    .hero-desc {
        font-size: 1rem;
    }
    
    .btn-lg {
        padding: 14px 28px;
        font-size: 16px;
    }
    
    .product-card,
    .advantage-card,
    .tech-card {
        padding: 30px 20px;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
    }
}

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

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

.animate-fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

.animate-fade-in {
    animation: fadeIn 0.6s ease forwards;
}

/* Utility Classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }
.mt-40 { margin-top: 40px; }
.mb-40 { margin-bottom: 40px; }

.hidden { display: none; }
.visible { display: block; }

/* Loading Spinner */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s linear infinite;
}

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