:root {
    --primary-color: #0f172a;
    --secondary-color: #1e293b;
    --accent-color: #d4af37; /* Gold */
    --text-color: #334155;
    --light-text: #94a3b8;
    --white: #ffffff;
    --bg-light: #f8fafc;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-light);
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

/* Header */
header {
    background-color: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 10px;
}

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

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    font-weight: 500;
    color: var(--secondary-color);
    position: relative;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--accent-color);
}

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

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

.mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Hero Section */
.hero {
    height: 80vh;
    background: linear-gradient(rgba(15, 23, 42, 0.8), rgba(15, 23, 42, 0.8)), url('https://images.unsplash.com/photo-1497366216548-37526070297c?auto=format&fit=crop&w=1920&q=80');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    margin-top: 60px;
}

.hero-content {
    max-width: 800px;
    padding: 0 20px;
    animation: fadeInUp 1s ease;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 800;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: var(--light-text);
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent-color);
    color: var(--white);
    border-radius: 5px;
    font-weight: 600;
    border: 2px solid var(--accent-color);
}

.btn:hover {
    background-color: transparent;
    color: var(--accent-color);
}

.btn-outline {
    background-color: transparent;
    border: 2px solid var(--white);
    margin-left: 1rem;
}

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

/* Section Common */
.section {
    padding: 5rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-header h2::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background-color: var(--accent-color);
    margin: 10px auto 0;
}

/* Services Grid */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
    transition: var(--transition);
    text-align: center;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.service-icon {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.service-card h3 {
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

/* About Section */
.about-preview {
    display: flex;
    align-items: center;
    gap: 4rem;
}

.about-image {
    flex: 1;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.about-text {
    flex: 1;
}

.about-text p {
    margin-bottom: 1.5rem;
    color: #64748b;
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 4rem 5% 1rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-col h3 {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    font-size: 1.2rem;
}

.footer-col p {
    color: var(--light-text);
    margin-bottom: 0.8rem;
}

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

.footer-links a {
    color: var(--light-text);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: var(--light-text);
    font-size: 0.9rem;
}

/* Page Header */
.page-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    text-align: center;
    padding: 8rem 5% 4rem;
    margin-top: 60px;
}

.page-header h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.page-header p {
    color: var(--light-text);
    font-size: 1.1rem;
    letter-spacing: 2px;
}

/* Download Section */
.download-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
}

.download-card {
    background: var(--white);
    padding: 3rem;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    text-align: center;
    max-width: 500px;
    width: 100%;
    transition: var(--transition);
}

.download-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 50px rgba(0,0,0,0.15);
}

.download-icon {
    font-size: 4rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.download-card h2 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.download-desc {
    color: var(--text-color);
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.download-info {
    background: var(--bg-light);
    padding: 1.5rem;
    border-radius: 10px;
    margin-bottom: 2rem;
}

.info-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 0.8rem;
    color: var(--text-color);
}

.info-item:last-child {
    margin-bottom: 0;
}

.info-item i {
    color: var(--accent-color);
}

.download-btn {
    width: 100%;
    padding: 15px 30px;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

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

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--white);
        flex-direction: column;
        padding: 2rem;
        box-shadow: 0 5px 10px rgba(0,0,0,0.05);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .about-preview {
        flex-direction: column;
    }
}