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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: #334155;
    background-color: #f8fafc;
    line-height: 1.6;
}

/* Fixed Left Sidebar */
#navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 280px;
    height: 100%;
    background-color: #ffffff;
    border-right: 1px solid #e2e8f0;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

h1, h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: #0f172a;
    padding: 12px;
    margin-bottom: 16px;
    border-bottom: 1px solid #e2e8f0;
}

#navbar h1 {
    font-size: 1.5rem;
    padding: 24px;
    margin: 0;
}

/* Sidebar Links */
.nav-link {
    display: block;
    padding: 16px 24px;
    color: #475569;
    text-decoration: none;
    border-bottom: 1px solid #f1f5f9;
    font-size: 0.95rem;
    font-weight: 500;
    transition: background-color 0.2s, color 0.2s;
}

.nav-link:hover {
    background-color: #f1f5f9;
    color: #2563eb;
}

.nav-link:focus-visible {
    background-color: #f1f5f9;
    color: #2563eb;
    outline: 2px solid #2563eb;
    outline-offset: -2px;
}

/* Main Document */
#main-doc {
    margin-left: 280px;
    padding: 40px 60px;
    max-width: 900px;
}

/* Section */
.main-section {
    margin-bottom: 40px;
}

.main-section header {
    font-size: 1.75rem;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 16px;
}

.main-section p {
    margin-bottom: 16px;
}

.main-section ul {
    margin-left: 24px;
    margin-bottom: 16px;
}

.main-section li {
    margin-bottom: 8px;
}

/* Code Element */
pre code {
    display: block;
    padding: 16px;
}

code {
    background-color: #0f172a;
    color: #38bdf8;
    padding: 8px;
    border-radius: 8px;
    font-family: "Courier New", Courier, monospace;
    font-size: 0.9rem;
    margin: 16px 0;
    overflow-x: auto;
}

/* Media Query Breakpoint for Smaller Screens */
@media (max-width: 768px) {
    #navbar {
        position: relative;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 2px solid #e2e8f0;
    }

    #main-doc {
        margin-left: 0;
        padding: 24px;
    }
}