/* ===== Global Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #1e3a8a;
    --primary-dark: #1e293b;
    --primary-light: #3b82f6;
    --secondary-color: #0ea5e9;
    --accent-color: #f59e0b;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --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, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    overflow-x: hidden;
}

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

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: all 0.3s ease;
}

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

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.logo-icon {
    font-size: 2rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--primary-light);
    transition: width 0.3s ease;
}

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

.nav-link:hover::after {
    width: 80%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--primary-color);
    border-radius: 3px;
    transition: all 0.3s ease;
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 50%, #0ea5e9 100%);
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="%23ffffff" fill-opacity="0.1" d="M0,96L48,112C96,128,192,160,288,160C384,160,480,128,576,122.7C672,117,768,139,864,138.7C960,139,1056,117,1152,101.3C1248,85,1344,75,1392,69.3L1440,64L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>');
    background-size: cover;
    background-position: bottom;
    opacity: 0.3;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.1);
}

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

.hero-title {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    text-shadow: 2px 2px 10px rgba(0, 0, 0, 0.3);
    letter-spacing: 2px;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 3rem;
    opacity: 0.95;
    font-weight: 300;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin-bottom: 3rem;
}

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

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    display: block;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

.cta-button {
    display: inline-block;
    padding: 1rem 3rem;
    background: var(--accent-color);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s ease;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
    background: #ea580c;
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
}

.mouse {
    width: 30px;
    height: 50px;
    border: 2px solid rgba(255, 255, 255, 0.6);
    border-radius: 20px;
    position: relative;
}

.mouse::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 10px;
    background: rgba(255, 255, 255, 0.8);
    border-radius: 2px;
    animation: scroll 2s infinite;
}

@keyframes scroll {
    0%, 100% { opacity: 0; transform: translateX(-50%) translateY(0); }
    50% { opacity: 1; transform: translateX(-50%) translateY(10px); }
}

/* ===== Services Section ===== */
.services-section {
    padding: 6rem 0;
    background: var(--bg-white);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--accent-color);
    border-radius: 2px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-top: 1.5rem;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    transition: all 0.4s ease;
    border: 1px solid rgba(0, 0, 0, 0.05);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-light), var(--secondary-color));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}

.service-card:hover::before {
    transform: scaleX(1);
}

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

.service-icon {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    display: inline-block;
    transition: transform 0.3s ease;
}

.service-card:hover .service-icon {
    transform: scale(1.1) rotate(5deg);
}

.service-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.service-description {
    color: var(--text-light);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.service-features {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.feature-tag {
    display: inline-block;
    padding: 0.4rem 1rem;
    background: var(--bg-light);
    color: var(--primary-light);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

/* ===== Advantages Section ===== */
.advantages-section {
    padding: 6rem 0;
    background: linear-gradient(135deg, #f8fafc 0%, #e0f2fe 100%);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.advantage-item {
    background: white;
    padding: 2.5rem 2rem;
    border-radius: 16px;
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

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

.advantage-icon {
    font-size: 4rem;
    margin-bottom: 1.5rem;
}

.advantage-item h3 {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-weight: 700;
}

.advantage-item p {
    color: var(--text-light);
    line-height: 1.8;
}

/* ===== About Section ===== */
.about-section {
    padding: 6rem 0;
    background: var(--bg-white);
}

.about-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-content {
    padding-right: 2rem;
}

.about-text {
    color: var(--text-light);
    line-height: 1.9;
    margin-bottom: 1.5rem;
    font-size: 1.05rem;
}

.about-features {
    display: flex;
    gap: 2rem;
    margin-top: 3rem;
}

.about-feature {
    text-align: center;
    padding: 1.5rem;
    background: var(--bg-light);
    border-radius: 12px;
    flex: 1;
}

.feature-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-light);
    margin-bottom: 0.5rem;
}

.feature-label {
    font-size: 0.9rem;
    color: var(--text-light);
}

.about-image {
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-placeholder {
    width: 100%;
    height: 400px;
    background: linear-gradient(135deg, #3b82f6 0%, #0ea5e9 100%);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    box-shadow: var(--shadow-lg);
}

.placeholder-icon {
    font-size: 6rem;
    margin-bottom: 1rem;
}

.image-placeholder p {
    font-size: 1.5rem;
    font-weight: 600;
}

/* ===== Contact Section ===== */
.contact-section {
    padding: 6rem 0;
    background: var(--bg-light);
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 3rem;
    margin-top: 3rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    gap: 1.5rem;
    padding: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
}

.contact-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(5px);
}

.contact-icon {
    font-size: 2.5rem;
}

.contact-details h4 {
    font-size: 1.2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

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

.contact-form {
    background: white;
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem 1.5rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.submit-button {
    width: 100%;
    padding: 1rem 2rem;
    background: var(--primary-light);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.submit-button:hover {
    background: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ===== Footer ===== */
.footer {
    background: var(--primary-dark);
    color: white;
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 2rem;
}

.footer-title {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: white;
}

.footer-description {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
}

.footer-heading {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    color: white;
}

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

.footer-links li {
    margin-bottom: 0.8rem;
}

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

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* ===== Back to Top Button ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-light);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s ease;
    z-index: 999;
}

.back-to-top.show {
    display: flex;
}

.back-to-top:hover {
    background: var(--primary-color);
    transform: translateY(-5px);
}

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
    .container {
        padding: 0 30px;
    }

    .services-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow-md);
        transform: scaleY(0);
        transform-origin: top;
        transition: transform 0.3s ease;
        max-height: 0;
        overflow: hidden;
    }

    .nav-menu.active {
        transform: scaleY(1);
        max-height: 500px;
    }

    .nav-link {
        padding: 1rem 2rem;
        border-radius: 0;
        border-bottom: 1px solid #f3f4f6;
    }

    .nav-link::after {
        display: none;
    }

    .logo {
        font-size: 1.5rem;
    }

    .logo-icon {
        font-size: 1.6rem;
    }

    .hero {
        height: auto;
        min-height: 100vh;
        padding: 100px 0 60px;
    }

    .hero-title {
        font-size: 2rem;
        line-height: 1.3;
        margin-bottom: 1rem;
        letter-spacing: 1px;
    }

    .hero-subtitle {
        font-size: 1rem;
        margin-bottom: 2rem;
    }

    .hero-stats {
        flex-direction: row;
        flex-wrap: wrap;
        gap: 1.5rem;
        justify-content: space-around;
        margin-bottom: 2rem;
    }

    .stat-item {
        flex: 0 0 45%;
    }

    .stat-number {
        font-size: 2rem;
    }

    .stat-label {
        font-size: 0.85rem;
    }

    .cta-button {
        padding: 0.9rem 2rem;
        font-size: 1rem;
    }

    .services-section,
    .advantages-section,
    .about-section,
    .contact-section {
        padding: 4rem 0;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .section-subtitle {
        font-size: 1rem;
    }

    .services-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .service-card {
        padding: 2rem;
    }

    .service-icon {
        font-size: 3rem;
    }

    .service-title {
        font-size: 1.3rem;
    }

    .advantages-grid {
        grid-template-columns: 1fr;
    }

    .advantage-item {
        padding: 2rem 1.5rem;
    }

    .about-wrapper {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .about-content {
        padding-right: 0;
    }

    .about-features {
        flex-wrap: wrap;
        gap: 1rem;
    }

    .about-feature {
        flex: 0 0 calc(50% - 0.5rem);
        padding: 1rem;
    }

    .feature-number {
        font-size: 1.5rem;
    }

    .image-placeholder {
        height: 300px;
    }

    .placeholder-icon {
        font-size: 4rem;
    }

    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .contact-form {
        padding: 2rem;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .back-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
        font-size: 1.3rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .nav-wrapper {
        padding: 0.8rem 0;
    }

    .logo {
        font-size: 1.3rem;
    }

    .logo-icon {
        font-size: 1.4rem;
    }

    .hero {
        padding: 80px 0 40px;
    }

    .hero-title {
        font-size: 1.5rem;
        letter-spacing: 0.5px;
    }

    .hero-subtitle {
        font-size: 0.9rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

    .stat-item {
        flex: 1 1 100%;
    }

    .stat-number {
        font-size: 2.5rem;
    }

    .cta-button {
        padding: 0.8rem 1.8rem;
        font-size: 0.95rem;
    }

    .services-section,
    .advantages-section,
    .about-section,
    .contact-section {
        padding: 3rem 0;
    }

    .section-header {
        margin-bottom: 2.5rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .section-subtitle {
        font-size: 0.9rem;
    }

    .service-card {
        padding: 1.5rem;
    }

    .service-icon {
        font-size: 2.5rem;
        margin-bottom: 1rem;
    }

    .service-title {
        font-size: 1.2rem;
    }

    .service-description {
        font-size: 0.95rem;
    }

    .feature-tag {
        padding: 0.3rem 0.8rem;
        font-size: 0.8rem;
    }

    .advantage-icon {
        font-size: 3rem;
        margin-bottom: 1rem;
    }

    .advantage-item h3 {
        font-size: 1.1rem;
    }

    .advantage-item p {
        font-size: 0.9rem;
    }

    .about-text {
        font-size: 0.95rem;
        margin-bottom: 1rem;
    }

    .about-features {
        flex-direction: column;
        gap: 1rem;
        margin-top: 2rem;
    }

    .about-feature {
        flex: 1 1 100%;
    }

    .image-placeholder {
        height: 250px;
    }

    .placeholder-icon {
        font-size: 3rem;
    }

    .image-placeholder p {
        font-size: 1.2rem;
    }

    .contact-item {
        padding: 1.5rem;
        gap: 1rem;
    }

    .contact-icon {
        font-size: 2rem;
    }

    .contact-details h4 {
        font-size: 1.1rem;
    }

    .contact-form {
        padding: 1.5rem;
    }

    .form-group {
        margin-bottom: 1rem;
    }

    .form-group input,
    .form-group textarea {
        padding: 0.9rem 1.2rem;
        font-size: 0.95rem;
    }

    .submit-button {
        padding: 0.9rem 1.5rem;
        font-size: 1rem;
    }

    .footer {
        padding: 2rem 0 1rem;
    }

    .footer-title {
        font-size: 1.5rem;
    }

    .footer-heading {
        font-size: 1.1rem;
        margin-bottom: 1rem;
    }

    .footer-links li {
        margin-bottom: 0.6rem;
    }

    .footer-links a {
        font-size: 0.9rem;
    }

    .footer-bottom {
        font-size: 0.85rem;
    }

    .back-to-top {
        width: 40px;
        height: 40px;
        bottom: 15px;
        right: 15px;
        font-size: 1.2rem;
    }

    .scroll-indicator {
        display: none;
    }
}