:root {
    --color-bg: #fafafa;
    --color-bg-card: #ffffff;
    --color-bg-navbar: rgba(255, 255, 255, 0.95);
    --color-text-primary: #1e293b;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-accent: #059669;
    --color-accent-hover: #047857;
    --color-border: #e2e8f0;
    --color-border-focus: #059669;
    --color-prefix: #059669;
    --color-comment: #64748b;
    --color-code-bg: #f1f5f9;
    --color-code-border: #e2e8f0;
    
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 6px 20px rgba(5, 150, 105, 0.12);
    --shadow-navbar: 0 1px 3px rgba(0, 0, 0, 0.08);
    
    --transition-fast: 0.15s ease;
    --transition-normal: 0.25s ease;
    --transition-slow: 0.4s ease;
    
    --font-mono: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', monospace;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    --navbar-height: 56px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg);
    color: var(--color-text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--color-bg-navbar);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-navbar);
    height: var(--navbar-height);
}

.navbar-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
    height: 100%;
    display: flex;
    align-items: center;
    gap: 16px;
}

.navbar-brand {
    display: flex;
    align-items: center;
    text-decoration: none;
    font-family: var(--font-mono);
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-primary);
    white-space: nowrap;
}

.brand-text {
    display: inline-block;
    min-width: 13ch;
}

.brand-prefix {
    color: var(--color-prefix);
}

.cursor {
    color: var(--color-accent);
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0; }
}

.breadcrumb {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 4px;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--color-text-muted);
    overflow-x: auto;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: 4px;
}

.breadcrumb-separator {
    color: var(--color-text-muted);
    user-select: none;
}

.breadcrumb-link {
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
}

.breadcrumb-link:hover {
    color: var(--color-accent);
    background-color: rgba(5, 150, 105, 0.08);
}

.breadcrumb-current {
    color: var(--color-text-primary);
    font-weight: 500;
}

.main-content {
    min-height: calc(100vh - var(--navbar-height) - 60px);
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 32px 20px;
}

.content-header {
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--color-border);
}

.content-title {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.content-title::before {
    content: '#';
    color: var(--color-prefix);
}

.directory-list {
    display: grid;
    gap: 12px;
    margin-bottom: 24px;
}

.directory-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: inherit;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
}

.directory-item:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-hover);
    transform: translateX(4px);
}

.directory-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
}

.directory-icon img {
    width: 20px;
    height: 20px;
    filter: brightness(0) saturate(100%) invert(29%) sepia(89%) saturate(748%) hue-rotate(132deg) brightness(94%) contrast(93%);
}

.directory-item:hover .directory-icon img {
    filter: brightness(0) saturate(100%) invert(28%) sepia(84%) saturate(612%) hue-rotate(129deg) brightness(93%) contrast(91%);
}

.directory-name {
    font-family: var(--font-mono);
    font-size: 0.95rem;
    color: var(--color-text-primary);
    flex: 1;
}

.directory-arrow {
    color: var(--color-accent);
    font-family: var(--font-mono);
    font-size: 0.9rem;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.directory-item:hover .directory-arrow {
    opacity: 1;
}

.markdown-body {
    background-color: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 32px;
    box-shadow: var(--shadow-sm);
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4,
.markdown-body h5,
.markdown-body h6 {
    font-family: var(--font-mono);
    color: var(--color-text-primary);
    margin-top: 24px;
    margin-bottom: 12px;
    font-weight: 600;
    line-height: 1.3;
}

.markdown-body h1 { font-size: 1.75rem; }
.markdown-body h2 { font-size: 1.5rem; }
.markdown-body h3 { font-size: 1.25rem; }
.markdown-body h4 { font-size: 1.1rem; }

.markdown-body h1::before { content: '# '; color: var(--color-prefix); }
.markdown-body h2::before { content: '## '; color: var(--color-prefix); }
.markdown-body h3::before { content: '### '; color: var(--color-prefix); }
.markdown-body h4::before { content: '#### '; color: var(--color-prefix); }

.markdown-body p {
    margin-bottom: 16px;
    color: var(--color-text-secondary);
}

.markdown-body a {
    color: var(--color-accent);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.markdown-body a:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

.markdown-body code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background-color: var(--color-code-bg);
    border: 1px solid var(--color-code-border);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    color: var(--color-text-primary);
}

.markdown-body pre {
    background-color: var(--color-code-bg);
    border: 1px solid var(--color-code-border);
    border-radius: var(--radius-md);
    padding: 16px;
    overflow-x: auto;
    margin-bottom: 16px;
}

.markdown-body pre code {
    background: none;
    border: none;
    padding: 0;
    font-size: 0.85rem;
    line-height: 1.6;
}

.markdown-body ul,
.markdown-body ol {
    margin-bottom: 16px;
    padding-left: 24px;
    color: var(--color-text-secondary);
}

.markdown-body li {
    margin-bottom: 8px;
}

.markdown-body li::marker {
    color: var(--color-accent);
}

.markdown-body blockquote {
    border-left: 3px solid var(--color-accent);
    padding-left: 16px;
    margin: 16px 0;
    color: var(--color-text-secondary);
    font-style: italic;
}

.markdown-body hr {
    border: none;
    border-top: 1px solid var(--color-border);
    margin: 24px 0;
}

.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 16px;
}

.markdown-body th,
.markdown-body td {
    border: 1px solid var(--color-border);
    padding: 10px 12px;
    text-align: left;
}

.markdown-body th {
    background-color: var(--color-code-bg);
    font-family: var(--font-mono);
    font-weight: 600;
}

.markdown-body img {
    max-width: 100%;
    border-radius: var(--radius-md);
    margin: 16px 0;
}

.footer {
    text-align: center;
    padding: 24px 20px;
    border-top: 1px solid var(--color-border);
    background-color: var(--color-bg-card);
}

.footer-text {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

.comment {
    color: var(--color-comment);
}

.footer-link {
    color: var(--color-accent);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.footer-link:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

.empty-state {
    text-align: center;
    padding: 48px 24px;
    color: var(--color-text-muted);
}

.empty-state-icon {
    font-family: var(--font-mono);
    font-size: 2rem;
    margin-bottom: 16px;
    color: var(--color-text-muted);
}

.empty-state-text {
    font-family: var(--font-mono);
    font-size: 0.9rem;
}

@media (max-width: 600px) {
    .navbar-container {
        padding: 0 16px;
    }
    
    .navbar-brand {
        font-size: 0.9rem;
    }
    
    .breadcrumb {
        font-size: 0.75rem;
    }
    
    .container {
        padding: 24px 16px;
    }
    
    .content-title {
        font-size: 1.25rem;
    }
    
    .markdown-body {
        padding: 20px;
    }
    
    .markdown-body h1 { font-size: 1.5rem; }
    .markdown-body h2 { font-size: 1.25rem; }
    .markdown-body h3 { font-size: 1.1rem; }
    
    .directory-item {
        padding: 14px 16px;
    }
}

@media (max-width: 400px) {
    .navbar-container {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
        padding: 8px 16px;
    }
    
    .navbar {
        height: auto;
        min-height: var(--navbar-height);
    }
}