/* Reset and base styles */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 60px;
}

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

body {
    font-family: "Microsoft YaHei", "微软雅黑", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
    overflow-x: hidden;
}

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

/* Header styles */
.header {
    background-color: #1a1a1a;
    padding: 10px 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

.logo {
    color: #fff;
    font-size: 20px;
    margin: 0;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
    z-index: 1001;
}

.mobile-menu-btn span {
    display: block;
    width: 25px;
    height: 2px;
    background-color: #fff;
    margin: 5px 0;
    transition: all 0.3s ease;
}

.nav ul {
    list-style: none;
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin: 0;
    padding: 0;
}

.nav a {
    color: #fff;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
    white-space: nowrap;
    padding: 5px 10px;
    border-radius: 4px;
}

.nav a:hover {
    color: #00a8ff;
    background: rgba(255,255,255,0.1);
}

/* Mobile Navigation */
@media (max-width: 991px) {
    .mobile-menu-btn {
        display: block;
    }

    .nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        background-color: #1a1a1a;
        padding: 80px 20px 20px;
        transition: right 0.3s ease;
        box-shadow: -2px 0 10px rgba(0,0,0,0.1);
    }

    .nav.active {
        right: 0;
    }

    .nav ul {
        flex-direction: column;
        gap: 20px;
    }

    .nav a {
        display: block;
        padding: 10px;
        font-size: 16px;
    }

    /* Hamburger menu animation */
    .mobile-menu-btn.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
}

@media (max-width: 575px) {
    .logo {
        font-size: 15px;
    }

    .nav {
        width: 100%;
        max-width: none;
    }
}

/* Hero section */
.hero {
    background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="100" height="100" viewBox="0 0 100 100"><rect width="100" height="100" fill="%231a1a1a"/><path d="M0 0L100 100M100 0L0 100" stroke="%23333" stroke-width="1"/></svg>');
    color: #fff;
    padding: 100px 0 60px;
    margin-top: 40px;
    min-height: 80vh;
    display: flex;
    align-items: center;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

.hero-text {
    text-align: left;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

.hero-img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    transition: transform 0.3s ease;
    object-fit: cover;
    max-height: 500px;
}

.hero-img:hover {
    transform: scale(1.02);
}

.hero h2 {
    font-size: 36px;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-subtitle {
    font-size: 18px;
    margin-bottom: 30px;
    color: rgba(255,255,255,0.9);
}

.hero-features {
    margin-top: 30px;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.hero-features span {
    background: rgba(255,255,255,0.1);
    padding: 8px 15px;
    border-radius: 20px;
    font-size: 14px;
    transition: transform 0.3s;
}

.hero-features span:hover {
    transform: translateY(-2px);
    background: rgba(255,255,255,0.2);
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-top: 50px;
}

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

.stat-number {
    display: block;
    font-size: 36px;
    font-weight: bold;
    color: #00a8ff;
    margin-bottom: 5px;
}

.stat-text {
    font-size: 14px;
    color: rgba(255,255,255,0.9);
}

/* Section styles */
section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 32px;
    margin-bottom: 50px;
    color: #1a1a1a;
    position: relative;
}

.section-title:after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: #00a8ff;
    margin: 15px auto 0;
}

/* Service cards */
.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin: 0 auto;
    max-width: 1400px;
}

.service-card {
    background: #fff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    height: 100%;
    display: flex;
    flex-direction: column;
    scroll-margin-top: 80px;
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.service-card h3 {
    color: #1a1a1a;
    margin-bottom: 15px;
    font-size: 20px;
    position: relative;
    padding-bottom: 10px;
}

.service-card h3:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: #00a8ff;
}

.service-card p {
    color: #666;
    margin-bottom: 20px;
}

.service-features {
    list-style: none;
    margin-top: 15px;
    padding-left: 0;
    flex-grow: 1;
}

.service-features li {
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
    color: #555;
}

.service-features li:before {
    content: "•";
    color: #00a8ff;
    position: absolute;
    left: 0;
    font-weight: bold;
}

.service-tag {
    position: absolute;
    top: 20px;
    right: -30px;
    background: #00a8ff;
    color: #fff;
    padding: 5px 30px;
    transform: rotate(45deg);
    font-size: 12px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

/* Why choose us section */
.why-choose-us {
    background: #f8f9fa;
}

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

.feature-item {
    text-align: center;
    padding: 30px;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.feature-item:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 40px;
    margin-bottom: 20px;
    display: block;
}

/* Advantage cards */
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.advantage-card {
    background: #fff;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.advantage-list {
    list-style: none;
    margin-top: 15px;
    text-align: left;
}

.advantage-list li {
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.advantage-list li:before {
    content: "✓";
    color: #00a8ff;
    position: absolute;
    left: 0;
}

/* Process steps */
.process-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    text-align: center;
}

.step {
    background: #fff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    position: relative;
}

.step-number {
    width: 40px;
    height: 40px;
    background: #00a8ff;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 20px;
    font-weight: bold;
}

.step h3 {
    color: #1a1a1a;
    margin-bottom: 15px;
}

.step-details {
    list-style: none;
    margin-top: 15px;
    text-align: left;
}

.step-details li {
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.step-details li:before {
    content: "→";
    color: #00a8ff;
    position: absolute;
    left: 0;
}

/* Contact section */
.contact {
    background-color: #1a1a1a;
    color: #fff;
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.contact-card {
    background: rgba(255,255,255,0.1);
    padding: 20px;
    border-radius: 10px;
    text-align: center;
}

.contact-features {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

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

.feature-icon {
    font-size: 24px;
}

/* Footer */
.footer {
    background-color: #1a1a1a;
    color: #fff;
    padding: 40px 0 20px;
}

.footer-content {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.footer-section h3 {
    color: #fff;
    font-size: 16px;
    margin-bottom: 15px;
    position: relative;
    padding-bottom: 8px;
}

.footer-section h3:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 2px;
    background: #00a8ff;
}

.footer-section p {
    color: rgba(255,255,255,0.7);
    line-height: 1.5;
    font-size: 13px;
}

.footer-links, .footer-contact {
    list-style: none;
    padding: 0;
}

.footer-links li, .footer-contact li {
    margin-bottom: 8px;
    color: rgba(255,255,255,0.7);
    font-size: 13px;
}

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

.footer-links a:hover {
    color: #00a8ff;
}

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

.footer-info h3 {
    margin-bottom: 8px;
    font-size: 18px;
}

.footer-info p {
    color: rgba(255,255,255,0.7);
    margin-bottom: 10px;
    font-size: 13px;
}

.footer-copyright {
    font-size: 12px;
    color: rgba(255,255,255,0.5);
}

.footer-copyright p {
    margin-bottom: 4px;
}

/* Responsive Design */
/* Large screens (1200px and up) */
@media (min-width: 1200px) {
    .container {
        max-width: 1140px;
    }

    .hero-content {
        gap: 60px;
    }

    .hero h2 {
        font-size: 42px;
    }

    .hero-subtitle {
        font-size: 20px;
    }
}

/* Medium screens (992px to 1199px) */
@media (max-width: 1199px) {
    .container {
        max-width: 960px;
    }

    .hero-content {
        gap: 40px;
    }

    .hero h2 {
        font-size: 36px;
    }
}

/* Tablets (768px to 991px) */
@media (max-width: 991px) {
    .container {
        max-width: 720px;
    }

    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 30px;
    }

    .hero-text {
        text-align: center;
    }

    .hero-features {
        justify-content: center;
    }

    .hero-stats {
        justify-content: center;
    }

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

    .hero-image {
        order: -1;
        margin-bottom: 30px;
    }

    .hero-img {
        max-width: 80%;
        max-height: 400px;
    }

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

/* Mobile Landscape (576px to 767px) */
@media (max-width: 767px) {
    .container {
        max-width: 540px;
    }

    .header {
        padding: 6px 0;
    }

    .logo {
        font-size: 16px;
    }

    .nav ul {
        flex-direction: column;
        gap: 10px;
    }

    .hero {
        padding: 70px 0 30px;
        margin-top: 25px;
        min-height: 60vh;
    }

    .hero h2 {
        font-size: 28px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }

    .section-title {
        font-size: 28px;
    }

    section {
        padding: 60px 0;
    }

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

    .service-card {
        padding: 20px;
    }

    .footer {
        padding: 30px 0 15px;
    }

    .footer-section h3 {
        font-size: 15px;
        margin-bottom: 12px;
    }

    .footer-links li, .footer-contact li {
        font-size: 12px;
        margin-bottom: 6px;
    }

    .hero-img {
        max-width: 100%;
        max-height: 300px;
    }
}

/* Mobile Portrait (up to 575px) */
@media (max-width: 575px) {
    .container {
        padding: 0 15px;
    }

    .hero h2 {
        font-size: 24px;
    }

    .hero-subtitle {
        font-size: 14px;
    }

    .hero-features span {
        font-size: 12px;
        padding: 6px 12px;
    }

    .section-title {
        font-size: 24px;
    }

    .service-card h3 {
        font-size: 18px;
    }

    .service-features li {
        font-size: 14px;
    }

    .hero-img {
        max-width: 100%;
    }

    .stat-number {
        font-size: 28px;
    }

    .stat-text {
        font-size: 12px;
    }

    .footer {
        padding: 25px 0 12px;
    }

    .footer-info h3 {
        font-size: 16px;
    }

    .footer-copyright {
        font-size: 11px;
    }
}

/* Print styles */
@media print {
    .header, .hero, .contact, .footer {
        display: none;
    }

    body {
        background: #fff;
        color: #000;
    }

    .container {
        max-width: 100%;
        padding: 0;
    }

    section {
        page-break-inside: avoid;
    }
}