/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

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

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    text-decoration: none;
}

.logo-img {
    height: 40px;
    width: auto;
    transition: opacity 0.3s;
}

.logo-img:hover {
    opacity: 0.8;
}

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

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #2563eb;
}

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

.hamburger span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 150px 0 100px;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 30px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    display: inline-block;
}

.btn-primary {
    background: #fff;
    color: #2563eb;
}

.btn-primary:hover {
    background: #f8fafc;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
}

.btn-secondary:hover {
    background: #fff;
    color: #2563eb;
}

/* Tutorials Section */
.tutorials {
    padding: 80px 0;
    background: #f8fafc;
}

.tutorials h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

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

.tutorial-card {
    background: #fff;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

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

.tutorial-card h3 {
    margin-bottom: 1rem;
    color: #1e293b;
}

.tutorial-card h3 a {
    text-decoration: none;
    color: inherit;
}

.tutorial-card h3 a:hover {
    color: #2563eb;
}

.tutorial-card p {
    color: #64748b;
    margin-bottom: 1rem;
}

.tutorial-meta {
    color: #2563eb;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Examples Section */
.examples {
    padding: 80px 0;
}

.examples h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

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

.example-card {
    background: #fff;
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    transition: all 0.3s;
}

.example-card:hover {
    border-color: #2563eb;
    transform: translateY(-3px);
}

.example-card h3 {
    margin-bottom: 1rem;
    color: #1e293b;
}

.example-card p {
    color: #64748b;
    margin-bottom: 1.5rem;
}

.example-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
}

.example-link:hover {
    text-decoration: underline;
}

/* Friendly Links Section */
.friendly-links {
    padding: 80px 0;
    background: #f8fafc;
}

.friendly-links h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.link-card {
    background: #fff;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: all 0.3s;
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
}

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

.link-icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
}

.link-content {
    flex: 1;
}

.link-content h3 {
    margin-bottom: 0.5rem;
    color: #1e293b;
    font-size: 1.25rem;
    font-weight: 600;
}

.link-content p {
    color: #64748b;
    margin-bottom: 1rem;
    line-height: 1.6;
}

.link-url {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s;
}

.link-url:hover {
    color: #1d4ed8;
    text-decoration: underline;
}

.link-url::after {
    content: "↗";
    font-size: 0.8rem;
    opacity: 0.7;
}

/* Footer */
.footer {
    background: #1e293b;
    color: #fff;
    padding: 40px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.footer-logo-img {
    height: 32px;
    width: auto;
    filter: brightness(0) invert(1);
}

.footer-logo p {
    color: #94a3b8;
    margin: 0;
}

.footer-info {
    text-align: right;
}

.footer-links {
    margin-top: 0.5rem;
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: #94a3b8;
    text-decoration: none;
    transition: color 0.3s;
}

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

@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-info {
        text-align: center;
    }

    .footer-links {
        justify-content: center;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: #fff;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hamburger {
        display: flex;
    }

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

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .tutorial-grid,
    .example-grid,
    .links-grid {
        grid-template-columns: 1fr;
    }

    .link-card {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }

    .link-icon {
        align-self: center;
    }
}

/* 
Active navigation link */
.nav-menu a.active {
    color: #2563eb;
    font-weight: 600;
}

/* About page specific styles */
.about-intro {
    margin-bottom: 3rem;
}

.about-intro .hero-content {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid #2563eb;
}

.about-intro h2 {
    color: #1e293b;
    margin-bottom: 1rem;
}

.about-intro p {
    line-height: 1.7;
    margin-bottom: 1rem;
}

.about-intro code {
    background: #e2e8f0;
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Monaco', 'Menlo', monospace;
    color: #2563eb;
    font-weight: 600;
}

.cta-section .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}