* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

:root {
    --primary-color: #0066ff;
    --secondary-color: #00d4ff;
    --dark-bg: #0a192f;
    --card-bg: rgba(20, 40, 70, 0.7);
    --text-color: #e6f1ff;
    --text-secondary: #8892b0;
    --accent-color: #64ffda;
    --gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    --border-radius: 12px;
}

body {
    background-color: var(--dark-bg);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
    background-image:
        radial-gradient(circle at 10% 20%, rgba(0, 102, 255, 0.1) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, rgba(0, 212, 255, 0.1) 0%, transparent 20%);
}

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

header {
    padding: 25px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(100, 255, 218, 0.1);
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
    text-decoration: none;
    transition: transform 0.3s ease;
}

.logo:hover {
    transform: translateY(-2px);
}

.logo-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    background: var(--gradient);
    position: relative;
    overflow: hidden;
}

.logo-icon::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.2) 50%, transparent 70%);
    animation: shine 3s infinite linear;
}

@keyframes shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.logo-icon-text {
    font-size: 20px;
    font-weight: 800;
    color: white;
    z-index: 1;
}

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

.logo-en {
    font-size: 28px;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    line-height: 1;
    letter-spacing: 1px;
}

.logo-cn {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 2px;
    letter-spacing: 3px;
}

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient);
    transition: width 0.3s;
}

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

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

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

.hero {
    text-align: center;
    padding: 80px 0 60px;
    position: relative;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    background: var(--gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    line-height: 1.2;
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto 40px;
}

.breadcrumb {
    display: flex;
    gap: 8px;
    padding: 16px 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
}

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

.section-title {
    font-size: 2.5rem;
    margin-bottom: 40px;
    text-align: center;
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--gradient);
    border-radius: 3px;
}

.section {
    padding: 80px 0;
}

.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
    margin-top: 30px;
}

.resource-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 28px;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid rgba(100, 255, 218, 0.1);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.6s ease-out;
}

.resource-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--gradient);
}

.resource-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 15px 30px rgba(0, 102, 255, 0.2);
}

.resource-card h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: var(--accent-color);
}

.resource-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
}

.card-tag {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 12px;
    background: rgba(0, 102, 255, 0.2);
    color: var(--secondary-color);
    border: 1px solid rgba(0, 212, 255, 0.2);
}

.resource-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    transition: color 0.3s, gap 0.2s;
}

.resource-link:hover {
    color: var(--secondary-color);
    gap: 10px;
}

.simple-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 24px;
    padding: 50px 0;
}

.nav-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 36px 24px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid rgba(100, 255, 218, 0.1);
    text-decoration: none;
    display: block;
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.6s ease-out;
}

.nav-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--gradient);
}

.nav-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 30px rgba(0, 102, 255, 0.2);
}

.nav-card h3 {
    color: var(--accent-color);
    font-size: 1.3rem;
    margin-bottom: 8px;
}

.nav-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

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

.bg-element {
    position: fixed;
    border-radius: 50%;
    background: rgba(0, 102, 255, 0.05);
    z-index: -1;
    pointer-events: none;
}

.bg-element-1 {
    width: 300px;
    height: 300px;
    top: 10%;
    left: 5%;
}

.bg-element-2 {
    width: 200px;
    height: 200px;
    bottom: 20%;
    right: 10%;
}

.footer {
    background: rgba(10, 25, 47, 0.9);
    padding: 20px 0;
    text-align: center;
    border-top: 1px solid rgba(100, 255, 218, 0.1);
    margin-top: 40px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.footer-links {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}

.footer a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer img {
    vertical-align: middle;
    margin-right: 4px;
}

.copyright {
    font-size: 0.8rem;
}

.simple-footer {
    background: rgba(10, 25, 47, 0.9);
    padding: 20px 0;
    text-align: center;
    border-top: 1px solid rgba(100, 255, 218, 0.1);
    margin-top: 40px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
        gap: 20px;
    }

    .nav-links {
        gap: 20px;
        flex-wrap: wrap;
        justify-content: center;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }

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

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

    .section {
        padding: 50px 0;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

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

    .logo-en {
        font-size: 24px;
    }

    .logo-cn {
        font-size: 12px;
    }

    .nav-links {
        gap: 12px;
        font-size: 0.9rem;
    }
}