:root {
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --header-bg: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --primary-color: #1e293b;
    --primary-hover: #2563eb;
    --accent-bg: #f1f5f9;
    --accent-border: #2563eb;
    --badge-bg: #f1f5f9;
    --badge-text: #334155;
    --code-bg: #f1f5f9;
    --main-section-bg: #ffffff;
    --folder-color: #3b82f6;
}

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

body {
    font-family: 'Source Sans 3', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    padding: 40px 20px;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px 0 rgba(0, 0, 0, 0.03);
    overflow: hidden;
}

.header {
    padding: 24px 32px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--header-bg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    flex-wrap: wrap;
}

.header-main {
    display: flex;
    align-items: center;
    gap: 20px;
    flex: 1 1 420px;
    min-width: 0;
}

.top-nav {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 8px;
    flex-wrap: wrap;
    margin-left: auto;
    padding: 0;
    background: transparent;
    border: none;
}

.nav-link {
    font-size: 13px;
    font-weight: 600;
    color: var(--primary-hover);
    text-decoration: none;
    padding: 6px 10px;
    border-radius: 999px;
    transition: background-color 0.15s ease, color 0.15s ease;
}

.nav-link:hover {
    background-color: var(--accent-bg);
    text-decoration: none;
}

.header-logo img {
    width: 56px;
    height: auto;
    display: block;
}

.header-info h1 {
    font-family: 'Merriweather', Georgia, serif;
    font-size: 22px;
    color: var(--primary-color);
    font-weight: 700;
    margin-bottom: 6px;
}

.header-info p {
    font-size: 13.5px;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.header-tag {
    background-color: var(--badge-bg);
    color: var(--badge-text);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    border: 1px solid var(--border-color);
}

.content {
    padding: 32px;
}

.main-problems-section {
    background: var(--main-section-bg);
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--accent-border);
    border-radius: 6px;
    padding: 24px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.03);
    margin-bottom: 36px;
}

.main-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-color);
}

.main-section-title {
    font-family: 'Merriweather', Georgia, serif;
    font-size: 17px;
    color: var(--primary-color);
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
}

.count-badge {
    background: var(--badge-bg);
    color: var(--badge-text);
    border: 1px solid var(--border-color);
    font-size: 12px;
    font-weight: 600;
    padding: 2px 10px;
    border-radius: 12px;
    display: none;
}

.section-title {
    font-family: 'Merriweather', Georgia, serif;
    font-size: 16px;
    color: var(--primary-color);
    margin-bottom: 12px;
    padding-bottom: 6px;
    border-bottom: 1px solid var(--border-color);
}

ul.tree-list {
    list-style: none;
    padding-left: 0;
}

ul.tree-list ul {
    list-style: none;
    padding-left: 20px;
    margin-top: 4px;
    border-left: 1px solid var(--border-color);
    margin-left: 10px;
}

li.tree-item {
    margin: 3px 0;
}

.folder-title, .file-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 14.5px;
    transition: background-color 0.15s ease, color 0.15s ease;
}

.folder-title {
    font-weight: 600;
    color: var(--text-main);
    cursor: pointer;
    user-select: none;
}

.folder-title:hover {
    background-color: var(--accent-bg);
    color: var(--primary-hover);
}

.folder-icon {
    font-style: normal;
    font-size: 12px;
    width: 14px;
    text-align: center;
    color: var(--folder-color);
}

.file-link {
    color: var(--text-main);
    text-decoration: none;
}

.file-link:hover {
    color: var(--primary-hover);
    background-color: var(--accent-bg);
}

.file-icon {
    font-style: normal;
    font-size: 13px;
    color: var(--text-muted);
    width: 14px;
    text-align: center;
}

.nested-container {
    display: none;
}

.nested-container.open {
    display: block;
}

.readme-container, .license-container {
    margin-top: 36px;
    padding: 24px;
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 6px;
}

.markdown-body {
    font-size: 14.5px;
    line-height: 1.7;
}

.markdown-body h1, .markdown-body h2, .markdown-body h3 {
    font-family: 'Merriweather', Georgia, serif;
    color: var(--primary-color);
    margin-top: 16px;
    margin-bottom: 12px;
}

.markdown-body p {
    margin-bottom: 12px;
}

.markdown-body code {
    background-color: var(--code-bg);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 13px;
}

.license-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 16px;
    margin-bottom: 20px;
}

.license-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 16px;
}

.license-card-header {
    margin-bottom: 12px;
    padding-bottom: 6px;
    border-bottom: 1px solid var(--border-color);
}

.badge {
    display: inline-block;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    padding: 3px 8px;
    border-radius: 4px;
    letter-spacing: 0.5px;
}

.badge-green {
    background-color: #dcfce7;
    color: #15803d;
}

.badge-blue {
    background-color: #dbeafe;
    color: #1e40af;
}

.badge-red {
    background-color: #fee2e2;
    color: #b91c1c;
}

.license-card ul {
    list-style: none;
    padding-left: 0;
    font-size: 13.5px;
}

.license-card li {
    position: relative;
    padding-left: 18px;
    margin-bottom: 8px;
    line-height: 1.5;
}

.license-card li::before {
    position: absolute;
    left: 0;
    top: 0;
    font-weight: bold;
}

.perm-card li::before {
    content: "✓";
    color: #16a34a;
}

.cond-card li::before {
    content: "•";
    color: #2563eb;
}

.limit-card li::before {
    content: "×";
    color: #dc2626;
}

.license-details {
    margin-top: 12px;
}

.license-details summary {
    font-size: 13.5px;
    font-weight: 600;
    color: var(--primary-hover);
    cursor: pointer;
    user-select: none;
    padding: 6px 0;
}

.license-details summary:hover {
    text-decoration: underline;
}

.license-pre {
    white-space: pre-wrap;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
    font-size: 12.5px;
    color: var(--text-muted);
    background: var(--bg-color);
    padding: 16px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    margin-top: 10px;
    overflow-x: auto;
    max-height: 240px;
    overflow-y: auto;
}

.status-msg {
    font-size: 14px;
    padding: 16px;
    border-radius: 4px;
    background-color: var(--accent-bg);
    color: var(--text-muted);
}

.faq-container {
    margin-top: 36px;
    padding: 24px;
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 6px;
}

.faq-list {
    display: grid;
    gap: 12px;
}

.faq-item {
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--bg-color);
}

.faq-question {
    padding: 12px 14px;
    font-weight: 600;
    font-size: 14.5px;
    color: var(--primary-color);
    border-bottom: 1px solid var(--border-color);
}

.faq-answer {
    padding: 12px 14px 14px;
    font-size: 14px;
    line-height: 1.6;
    color: var(--text-muted);
}

.footer {
    padding: 16px 32px;
    background-color: var(--header-bg);
    border-top: 1px solid var(--border-color);
    font-size: 13px;
    display: flex;
    justify-content: flex-end;
    gap: 20px;
    color: var(--text-muted);
}

.footer a {
    color: var(--primary-hover);
    text-decoration: none;
    font-weight: 500;
}

.footer a:hover {
    text-decoration: underline;
}

@media (max-width: 560px) {
    body {
        padding: 16px 12px;
    }

    .header {
        padding: 18px 16px;
        gap: 12px;
        align-items: flex-start;
    }

    .header-main {
        width: 100%;
        flex: 1 1 100%;
    }

    .top-nav {
        width: 100%;
        justify-content: flex-start;
        gap: 6px;
    }

    .nav-link {
        font-size: 12px;
        padding: 5px 8px;
    }

    .header-logo {
        width: 46px;
    }

    .header-info h1 {
        font-size: 18px;
    }

    .header-info p {
        font-size: 12px;
    }

    .content,
    .main-problems-section,
    .readme-container,
    .license-container,
    .faq-container {
        padding-left: 14px;
        padding-right: 14px;
    }

    .footer {
        justify-content: center;
        padding: 14px 16px;
        font-size: 12px;
    }
}