:root {
    --primary: #2C3E50;
    --secondary: #34495E;
    --accent: #3498DB;
    --light: #ECF0F1;
    --lighter: #F8F9FA;
    --text: #333333;
    --text-light: #7F8C8D;
    --border: #BDC3C7;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    --radius: 8px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: var(--text);
    background-color: var(--lighter);
    -webkit-font-smoothing: antialiased;
}

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

/* Header */
header {
    background-color: white;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
}

.logo span {
    color: var(--accent);
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

nav ul li a:hover {
    color: var(--accent);
}

nav ul li a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--accent);
    transition: var(--transition);
}

nav ul li a:hover::after {
    width: 100%;
}

.mobile-menu {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

/* Hero Section */
.hero {
    background: url('./banner.jpg') no-repeat center center/cover;
    color: white;
    padding: 150px 0;
    text-align: center;
}

.hero h1 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero p {
    font-size: 20px;
    max-width: 700px;
    margin: 0 auto 30px;
    opacity: 0.9;
}

.cta-button {
    display: inline-block;
    background-color: var(--accent);
    color: white;
    padding: 12px 30px;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: 2px solid var(--accent);
}

.cta-button:hover {
    background-color: transparent;
    color: white;
}

.secondary-button {
    background-color: transparent;
    border: 2px solid white;
    margin-left: 15px;
}

.secondary-button:hover {
    background-color: white;
    color: var(--primary);
}
.model-button{
    background-color: yellow;
    border: 2px solid yellow; /* 将白色改为绿色 */
    color: #000;
    margin-top: 15px;
}

/* Problem Section */
.problem-section {
    padding: 80px 0;
    background-color: white;
}

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

.section-title h2 {
    font-size: 36px;
    color: var(--primary);
    margin-bottom: 15px;
}

.section-title p {
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto;
}

.problem-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.problem-card {
    background-color: var(--lighter);
    padding: 30px;
    border-radius: var(--radius);
    transition: var(--transition);
    text-align: center;
}

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

.problem-icon {
    font-size: 40px;
    color: var(--accent);
    margin-bottom: 20px;
}

.problem-card h3 {
    margin-bottom: 15px;
    color: var(--primary);
}

/* Solution Section */
.solution-section {
    padding: 80px 0;
    background-color: var(--lighter);
}

.solution-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.solution-card {
    background-color: white;
    padding: 30px;
    border-radius: var(--radius);
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.solution-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.solution-icon {
    font-size: 40px;
    color: var(--accent);
    margin-bottom: 20px;
}

.solution-card h3 {
    margin-bottom: 15px;
    color: var(--primary);
}

/* Selection Section */
.selection-section {
    padding: 80px 0;
    background-color: white;
}

.filter-options {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
}

.filter-button {
    padding: 10px 20px;
    background-color: var(--lighter);
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.filter-button:hover, .filter-button.active {
    background-color: var(--accent);
    color: white;
}

.car-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
}

.car-card {
    background-color: white;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.car-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.car-image {
    height: 200px;
    background-color: #eee;
    background-size: cover;
    background-position: center;
}

.car-info {
    padding: 20px;
}

.car-info h3 {
    margin-bottom: 10px;
    color: var(--primary);
}

.car-meta {
    display: flex;
    justify-content: space-between;
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 15px;
}

.car-price {
    font-weight: 700;
    color: var(--accent);
    font-size: 18px;
    margin-bottom: 15px;
}

.car-link {
    display: inline-block;
    width: 100%;
    padding: 10px;
    text-align: center;
    background-color: var(--primary);
    color: white;
    text-decoration: none;
    border-radius: var(--radius);
    transition: var(--transition);
}

.car-link:hover {
    background-color: var(--secondary);
}

/* Guarantee Section */
.guarantee-section {
    padding: 80px 0;
    background-color: var(--lighter);
}

.guarantee-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.guarantee-card {
    background-color: white;
    padding: 30px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.guarantee-card:hover {
    transform: translateY(-5px);
}

.guarantee-icon {
    font-size: 40px;
    color: var(--accent);
    margin-bottom: 20px;
}

/* Testimonials */
.testimonial-section {
    padding: 80px 0;
    background-color: white;
}

.testimonial-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.testimonial-card {
    background-color: var(--lighter);
    padding: 30px;
    border-radius: var(--radius);
    position: relative;
    box-shadow: var(--shadow);
}

.testimonial-card::before {
    content: '"';
    position: absolute;
    top: 20px;
    left: 20px;
    font-size: 60px;
    color: var(--accent);
    opacity: 0.2;
    font-family: serif;
    line-height: 1;
}

.testimonial-content {
    margin-bottom: 20px;
    font-style: italic;
    position: relative;
    z-index: 1;
}

.testimonial-author {
    font-weight: 600;
    color: var(--primary);
}

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

/* CTA Section */
.cta-section {
    padding: 100px 0;
    background: linear-gradient(135deg, rgba(44, 62, 80, 0.9) 0%, rgba(52, 73, 94, 0.9) 100%), url('https://images.unsplash.com/photo-1485291571150-772bcfc10da5?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80') no-repeat center center/cover;
    color: white;
    text-align: center;
}

.cta-section h2 {
    font-size: 36px;
    margin-bottom: 20px;
}

.cta-section p {
    max-width: 700px;
    margin: 0 auto 30px;
    opacity: 0.9;
}

/* Footer */
footer {
    background-color: var(--primary);
    color: white;
    padding: 60px 0 20px;
}

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

.footer-logo {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 20px;
    display: block;
    color: white;
    text-decoration: none;
}

.footer-logo span {
    color: var(--accent);
}

.footer-about p {
    opacity: 0.8;
    margin-bottom: 20px;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    text-decoration: none;
    transition: var(--transition);
}

.social-link:hover {
    background-color: var(--accent);
    transform: translateY(-3px);
}

.footer-links h3 {
    color: white;
    margin-bottom: 20px;
    font-size: 18px;
}

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

.footer-links ul li {
    margin-bottom: 10px;
}

.footer-links ul li a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links ul li a:hover {
    color: var(--accent);
    padding-left: 5px;
}

.footer-contact p {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
    opacity: 0.8;
}

.footer-contact i {
    margin-right: 10px;
    color: var(--accent);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
    font-size: 14px;
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        padding: 15px 0;
    }

    nav {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background-color: white;
        padding: 20px;
        box-shadow: var(--shadow);
        transform: translateY(-150%);
        transition: var(--transition);
        z-index: 99;
    }

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

    nav ul {
        flex-direction: column;
    }

    nav ul li {
        margin: 0 0 15px 0;
    }

    .mobile-menu {
        display: block;
    }

    .hero h1 {
        font-size: 36px;
    }

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

    .section-title h2 {
        font-size: 30px;
    }

    .cta-section h2 {
        font-size: 30px;
    }

    .secondary-button {
        margin-left: 0;
        margin-top: 15px;
    }
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

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

.delay-1 {
    animation-delay: 0.2s;
}

.delay-2 {
    animation-delay: 0.4s;
}

.delay-3 {
    animation-delay: 0.6s;
}