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

:root {
    --primary-color: #4a90e2;
    --primary-hover: #357abd;
    --text-primary: #333;
    --text-secondary: #666;
    --text-light: #999;
    --bg-light: #f5f7fa;
    --border-color: #e0e6ed;
    --disabled-bg: #e8eaed;
    --disabled-text: #999;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: #fff;
    margin: 0;
}

.navbar {
    background: #fff;
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-img {
    height: 40px;
    width: auto;
    display: block;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

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

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.2s;
}

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

.hero-section {
    background: var(--bg-light);
    padding: 4rem 2rem;
    text-align: center;
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 3rem;
}

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

.download-group {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 2rem;
}

.download-group h3 {
    font-size: 1.25rem;
    color: var(--text-primary);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.dev-tag {
    display: inline-block;
    background: #ff9800;
    color: #fff;
    font-size: 0.75rem;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    font-weight: 600;
}

.download-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    background: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: 6px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s;
    margin-bottom: 0.75rem;
}

.download-btn:last-child {
    margin-bottom: 0;
}

.download-btn:hover:not(.disabled) {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.download-btn.disabled {
    background: var(--disabled-bg);
    color: var(--disabled-text);
    cursor: not-allowed;
}

.download-icon {
    width: 18px;
    height: 18px;
}

.version-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    color: var(--text-light);
    font-size: 0.9rem;
}

.separator {
    color: var(--border-color);
}

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

.version-info a:hover {
    text-decoration: underline;
}

.screenshots-section {
    padding: 4rem 2rem;
    background: #fff;
}

.screenshots-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

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

.screenshot-img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    background: var(--bg-light);
    aspect-ratio: 16/10;
    object-fit: cover;
}

.screenshot-caption {
    margin-top: 1rem;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.features-section {
    padding: 4rem 2rem;
    background: var(--bg-light);
}

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

.section-title {
    font-size: 2rem;
    text-align: center;
    color: var(--text-primary);
    margin-bottom: 3rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.feature-item {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    transition: all 0.3s ease;
    cursor: default;
}

.feature-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    border-color: var(--primary-color);
}

.feature-icon {
    width: 56px;
    height: 56px;
    margin: 0 auto 1.5rem;
    background: #4a90e2;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: #fff;
}

.feature-item h3 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    text-align: center;
    font-weight: 600;
}

.feature-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
    text-align: center;
}

.changelog-section {
    padding: 4rem 2rem;
    background: var(--bg-light);
}

.changelog-list {
    max-width: 800px;
    margin: 0 auto;
}

.about-section {
    padding: 4rem 2rem;
    background: #fff;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.author-card {
    background: var(--bg-light);
    border-radius: 12px;
    padding: 2.5rem;
    border: 1px solid var(--border-color);
}

.author-info {
    margin-bottom: 1.5rem;
    text-align: center;
}

.author-info h3 {
    font-size: 1.8rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.author-title {
    color: var(--text-secondary);
    font-size: 1rem;
}

.author-description {
    line-height: 1.8;
}

.author-description p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    text-align: justify;
}

.author-link {
    display: inline-block;
    margin-top: 1rem;
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: #fff;
    text-decoration: none;
    border-radius: 6px;
    transition: all 0.2s;
}

.author-link:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
}

.links-section {
    padding: 4rem 2rem;
    background: var(--bg-light);
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    max-width: 900px;
    margin: 0 auto;
}

.link-item {
    display: block;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    text-decoration: none;
    transition: all 0.3s;
}

.link-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-color: var(--primary-color);
}

.link-name {
    display: block;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.link-desc {
    display: block;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.changelog-item {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.changelog-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.changelog-version {
    background: var(--primary-color);
    color: #fff;
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.9rem;
    font-weight: 600;
}

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

.changelog-content {
    list-style: none;
    padding-left: 0;
}

.changelog-content li {
    color: var(--text-secondary);
    padding-left: 1.5rem;
    position: relative;
    margin-bottom: 0.5rem;
}

.changelog-content li:before {
    content: "•";
    position: absolute;
    left: 0.5rem;
    color: var(--primary-color);
}

.footer {
    background: #fff;
    border-top: 1px solid var(--border-color);
    padding: 2rem;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.2s;
}

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

.footer-copyright {
    color: var(--text-light);
    font-size: 0.85rem;
}

@media (max-width: 768px) {
    .nav-container {
        padding: 0 1rem;
        flex-direction: column;
        gap: 1rem;
    }

    .nav-logo {
        justify-content: center;
    }

    .logo-img {
        height: 32px;
    }

    .logo-text {
        font-size: 1.25rem;
    }

    .nav-links {
        gap: 1.5rem;
        justify-content: center;
        width: 100%;
    }

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

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

    .hero-subtitle {
        font-size: 1.2rem;
    }

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

    .download-area {
        grid-template-columns: 1fr;
    }

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

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

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

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

    .author-card {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .navbar {
        padding: 0.75rem 0;
    }

    .nav-container {
        gap: 0.75rem;
    }

    .logo-img {
        height: 28px;
    }

    .logo-text {
        font-size: 1.1rem;
    }

    .nav-links {
        gap: 1rem;
    }

    .nav-links a {
        font-size: 0.85rem;
    }

    .hero-section {
        padding: 2.5rem 1rem;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

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

    .download-group {
        padding: 1.5rem;
    }

    .download-group h3 {
        font-size: 1.1rem;
    }

    .download-btn {
        font-size: 0.9rem;
        padding: 0.75rem 1.25rem;
    }

    .section-title {
        font-size: 1.35rem;
    }

    .feature-item {
        padding: 1.25rem;
    }

    .author-info h3 {
        font-size: 1.5rem;
    }

    .author-description p {
        font-size: 0.95rem;
    }

    .footer-links {
        gap: 1rem;
        flex-direction: column;
    }

    .footer-links a {
        font-size: 0.85rem;
    }
}