body {
    font-family: 'Courier New', Courier, monospace;
    background-color: #FFFFFF;
    color: #262626;
}
.header {
    background-color: #171717;
    padding: 1rem;
    color: white;
}
.nav-link {
    display: inline-block;
    padding: 0.5rem 1rem;
    margin: 0.25rem;
    border: 1px solid #525252;
    border-radius: 0.25rem;
    color: #A3A3A3;
    text-decoration: none;
    transition: all 0.2s ease;
    background-color: #262626;
}
.nav-link:hover {
    background-color: #737373;
    color: #FFFFFF;
    border-color: #737373;
}
.nav-link.active {
    background-color: #404040;
    color: #FFFFFF;
    font-weight: bold;
    border-color: #404040;
}
.main-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}
#content {
    padding: 2rem 0;
}
#markdown-content {
    background-color: #f5f5f5;
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    line-height: 1.6;
}
#markdown-content h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #525252;
}
#markdown-content h2 {
    font-size: 1.5rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    padding-bottom: 0.25rem;
    border-bottom: 1px solid #737373;
}
#markdown-content h3 {
    font-size: 1.25rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}
#markdown-content ul, #markdown-content ol {
    padding-left: 1.5rem;
    margin-bottom: 1rem;
}
#markdown-content ul {
    list-style-type: disc;
}
#markdown-content ol {
    list-style-type: decimal;
}
#markdown-content pre {
    background-color: #262626;
    color: #ffffff;
    padding: 1rem;
    border-radius: 0.25rem;
    overflow-x: auto;
    margin: 1rem 0;
}
#markdown-content code {
    background-color: #d4d4d4;
    padding: 0.2rem 0.4rem;
    border-radius: 0.25rem;
    font-family: monospace;
}
#markdown-content pre code {
    background-color: transparent;
    padding: 0;
}
#markdown-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
}
#markdown-content th, #markdown-content td {
    border: 1px solid #d4d4d4;
    padding: 0.5rem 1rem;
    text-align: left;
}
#markdown-content th {
    background-color: #e5e5e5;
}
#markdown-content blockquote {
    border-left: 4px solid #737373;
    padding-left: 1rem;
    margin: 1rem 0;
    color: #525252;
}
#markdown-content a {
    color: #0ea5e9;
    text-decoration: none;
}
#markdown-content a:hover {
    text-decoration: underline;
}
#sidebar {
    width: 250px;
    min-width: 250px;
    padding-right: 1.5rem;
}

/* Book-specific styling with grayscale ink effect */
.book-container {
    position: relative;
}

.book-content {
    /* Apply grayscale ink effect */
    filter: grayscale(100%) contrast(120%) brightness(0.95);
    background-color: #fafafa;
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    margin-bottom: 1rem;
    /* Subtle paper texture effect */
    background-image: 
        linear-gradient(45deg, transparent 24%, rgba(64, 64, 64, 0.02) 25%, rgba(64, 64, 64, 0.02) 26%, transparent 27%, transparent 74%, rgba(64, 64, 64, 0.02) 75%, rgba(64, 64, 64, 0.02) 76%, transparent 77%, transparent),
        linear-gradient(-45deg, transparent 24%, rgba(64, 64, 64, 0.02) 25%, rgba(64, 64, 64, 0.02) 26%, transparent 27%, transparent 74%, rgba(64, 64, 64, 0.02) 75%, rgba(64, 64, 64, 0.02) 76%, transparent 77%, transparent);
    background-size: 20px 20px;
}

/* Enhanced typography for book content */
.book-content h1 {
    font-size: 2.25rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 3px solid #404040;
    color: #171717;
    font-weight: bold;
}

.book-content h2 {
    font-size: 1.75rem;
    margin-top: 2.5rem;
    margin-bottom: 1.25rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #525252;
    color: #262626;
}

.book-content h3 {
    font-size: 1.375rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: #404040;
}

.book-content p {
    margin-bottom: 1.25rem;
    line-height: 1.8;
    text-align: justify;
    color: #262626;
}

.book-content ul, .book-content ol {
    margin-bottom: 1.5rem;
    padding-left: 2rem;
}

.book-content li {
    margin-bottom: 0.5rem;
    line-height: 1.7;
}

.book-content code {
    background-color: #e5e5e5;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-family: 'Courier New', Courier, monospace;
    color: #171717;
    font-weight: bold;
}

.book-content pre {
    background-color: #171717;
    color: #f5f5f5;
    padding: 1.5rem;
    border-radius: 0.5rem;
    overflow-x: auto;
    margin: 1.5rem 0;
    border: 1px solid #404040;
}

.book-content pre code {
    background-color: transparent;
    padding: 0;
    color: #f5f5f5;
    font-weight: normal;
}

/* Book navigation styling */
.book-navigation {
    margin-top: 2rem;
}

.book-nav-btn {
    background-color: #404040;
    color: #ffffff;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.375rem;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.875rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.2s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.book-nav-btn:hover {
    background-color: #525252;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.book-nav-btn:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.book-nav-btn:focus {
    outline: 2px solid #525252;
    outline-offset: 2px;
}

.book-nav-btn.prev {
    text-align: left;
}

.book-nav-btn.next {
    text-align: right;
}

/* Book chapter navigation in sidebar */
.book-chapter {
    font-size: 0.875rem;
    color: #525252;
    padding-left: 1rem;
    border-left: 2px solid #d4d4d4;
}

.book-chapter:hover {
    border-left-color: #737373;
    background-color: #f5f5f5;
}

.book-chapter.font-bold {
    border-left-color: #404040;
    background-color: #e5e5e5;
}

/* Mermaid diagram styling */
.mermaid-diagram {
    text-align: center;
    margin: 2rem 0;
    background-color: #fafafa;
    padding: 1rem;
    border-radius: 0.5rem;
    border: 1px solid #d4d4d4;
}

.mermaid-diagram svg {
    max-width: 100%;
    height: auto;
}