/* CSS Variables */
:root {
    /* Colors */
    --color-logo: #083452;
    --color-logo-light: #1A5981;
    --color-primary: #1a1a2e;           /* Dark navy blue */
    --color-primary-light: #16213e;
    --color-secondary: #0f3460;         /* Deep blue */
    --color-accent: #009688;            /* Teal */
    --color-accent-light: #4db6ac;
    --color-text: #333333;
    --color-text-light: #666666;
    --color-text-lighter: #888888;
    --color-bg: #ffffff;
    --color-bg-light: #f8f9fa;
    --color-border: #e0e0e0;
    --color-border-light: #f0f0f0;
    --color-code-bg: #f5f5f5;
    --color-code-border: #ddd;
    --color-code-text: #222;

    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: "SF Mono", "Monaco", "Inconsolata", "Fira Code", "Fira Mono", "Droid Sans Mono", Consolas, monospace;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;

    /* Layout */
    --max-width: 800px;
    --sidebar-width: 250px;
    --nav-height: 60px;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
}

/* ========================================
   Base Reset & Normalization
   ======================================== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    line-height: 1.2;
    margin-bottom: var(--space-md);
    color: var(--color-primary);
    font-weight: 600;
}

h1 { font-size: 2rem; margin-bottom: var(--space-xl); }
h2 { font-size: 1.4rem; margin-top: var(--space-xl); }
h3 { font-size: 1.2rem; margin-top: var(--space-lg); }
h4 { font-size: 1.1rem; }
h5, h6 { font-size: 1rem; }

p {
    margin-bottom: var(--space-md);
}

ul, ol {
    margin-bottom: var(--space-md);
    padding-left: var(--space-lg);
}

li {
    margin-bottom: var(--space-xs);
}

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

a:hover {
    color: var(--color-accent-light);
    text-decoration: underline;
}

code, pre {
    font-family: var(--font-mono);
}

/* ========================================
   Layout Components
   ======================================== */

/* Container */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

/* ========================================
   Header & Navigation
   ======================================== */

/* Mobile Navigation Header */
.mobile-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-md) var(--space-md);
    background: white;
    border-bottom: 1px solid var(--color-border);
}

.mobile-header a.nav-home {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-logo);
}

.mobile-header a.nav-home:hover {
    text-decoration: none;
    color: var(--color-logo-light);
}

.nav-toggle {
    background: white;
    color: var(--color-primary);
    border: none;
    width: var(--nav-height);
    height: var(--nav-height);
    border-radius: 4px;
    cursor: pointer;
    padding: 0;
    font-size: 1.5rem;
    margin-left: auto;
}

@media (min-width: 768px) {
    .mobile-header {
        display: none;
    }
}

/* Mobile Navigation - Checkbox Toggle */
.nav-toggle-checkbox {
    display: none;
}

.nav-toggle-checkbox:focus ~ .nav-toggle {
    outline: 2px solid var(--color-accent);
}

.nav-toggle {
    display: block;
    margin: var(--space-md) var(--space-md) var(--space-sm) auto;
    background: var(--color-primary);
    color: white;
    border: none;
    width: var(--nav-height);
    height: var(--nav-height);
    border-radius: 4px;
    cursor: pointer;
    padding: 0;
    font-size: 1.5rem;
    position: relative;
}

.nav-toggle .icon {
    display: block;
    width: 18px;
    height: 2px;
    background: white;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.nav-toggle .icon::before,
.nav-toggle .icon::after {
    content: '';
    position: absolute;
    width: 18px;
    height: 2px;
    background: white;
    left: 50%;
    transform: translateX(-50%);
}

.nav-toggle .icon::before { top: -6px; }
.nav-toggle .icon::after { top: 6px; }

.nav-toggle-checkbox:checked ~ .mobile-header .nav-toggle .icon {
    background: transparent;
}

.nav-toggle-checkbox:checked ~ .mobile-header .nav-toggle .icon::before {
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotate(45deg);
}

.nav-toggle-checkbox:checked ~ .mobile-header .nav-toggle .icon::after {
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) rotate(-45deg);
}

/* Mobile Navigation Menu - curtain animation */
.nav-menu {
    display: block;
    width: 100%;
    max-height: 0;
    overflow: hidden;
    color: white;
    background: var(--color-primary);
    padding: 0 var(--space-md);
    transition: max-height var(--transition-normal), padding-top var(--transition-normal), padding-bottom var(--transition-normal);
}

#nav-toggle:checked ~ .nav-menu {
    max-height: 1000px;
    padding-top: var(--space-md);
    padding-bottom: var(--space-md);
}

@media (min-width: 768px) {
    .mobile-header,
    .nav-menu,
    .nav-toggle-checkbox,
    .nav-toggle {
        display: none;
    }
}

.nav-toggle-checkbox:checked ~ .nav-menu {
    max-height: 1000px;
    padding: calc(var(--nav-height) + var(--space-lg)) var(--space-md) var(--space-md);
}

.nav-menu a {
    display: block;
    color: white;
    padding: var(--space-sm) 0;
    font-size: 1.1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-menu a:hover {
    color: var(--color-accent-light);
    text-decoration: none;
}

.nav-menu .nav-home {
    font-weight: 600;
    font-size: 1.2rem;
    padding-bottom: var(--space-md);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    margin-bottom: var(--space-md);
}



/* Desktop Navigation */
.header-nav {
    display: none;
}


/* Fancy heading styling */

main.fancy-headings h2 {
    position: relative;
    padding-bottom: var(--space-sm);
}

main.fancy-headings h2 {
    margin-top: var(--space-xl);
    padding-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
}

main.fancy-headings h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 3px;
    background: var(--color-accent);
}

/* Sidebar anchor links */
.sidebar-nav {
    position: sticky;
    top: var(--space-xl);
    padding: var(--space-md);
    background: var(--color-bg-light);
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.sidebar-nav h3 {
    font-size: 1rem;
    margin-bottom: var(--space-md);
    color: var(--color-primary);
    border-bottom: 1px solid var(--color-border);
    padding-bottom: var(--space-sm);
}

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

.sidebar-nav li {
    margin-bottom: var(--space-sm);
}

.sidebar-nav a {
    display: block;
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
    font-size: 0.9rem;
    color: var(--color-text);
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
    background: var(--color-accent);
    color: white;
}

/* ========================================
   Main Content Styling
   ======================================== */

main {
    padding: var(--space-lg) 0;
}

main > h1:first-child {
    margin-top: var(--space-xl);
}

/* Ensure space below sticky header on desktop */


/* Footer */
footer {
    padding: var(--space-xl) 0;
    margin-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-text-light);
    font-size: 0.8rem;
}

/* ========================================
   Blog Layout
   ======================================== */

.blog-index {
    max-width: var(--max-width);
    padding: 0 var(--space-md);
}

.blog-index aside {
    margin-bottom: var(--space-lg);
    margin-top: var(--space-sm);
    text-align: right;
}

.blog-index aside a {
    display: inline-block;
    color: var(--color-accent);
}

.blog-index div.post-list {
    padding: var(--space-lg) 0;
}

.blog-index div.post-list-item {
    margin-bottom: var(--space-xl);
    padding-bottom: var(--space-xl);
    border-bottom: 1px solid var(--color-border);
}

.blog-index div.post-list-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.blog-index div.post-list-item header {
    margin-bottom: var(--space-md);
}

.blog-index div.post-list-item header p {
    color: var(--color-text-light);
    font-size: 0.9rem;
}

.blog-index div.post-list-item h2 {
    font-size: 1.4rem;
    margin: var(--space-sm) 0;
}

/* Blog post layout */
.blog-post {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.blog-post article {
    background: var(--color-bg);
    border-radius: 8px;
    padding: var(--space-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.blog-post article header {
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--color-border);
}

.blog-post article header p {
    color: var(--color-text-light);
    font-size: 0.9rem;
}

.blog-post article h1 {
    font-size: 1.8rem;
}

/* ========================================
   Code & Quote Blocks
   ======================================== */

/* Code blocks */
pre {
    background: var(--color-code-bg);
    border: 1px solid var(--color-code-border);
    border-radius: 4px;
    padding: var(--space-md);
    overflow-x: auto;
    margin-bottom: var(--space-md);
    font-size: 0.9rem;
    line-height: 1.5;
}

pre code {
    background: transparent;
    padding: 0;
    color: var(--color-code-text);
}

/* Inline code */
code {
    background: var(--color-code-bg);
    padding: 0.1em 0.3em;
    border-radius: 3px;
    font-size: 0.9em;
    color: var(--color-code-text);
}

/* Blockquotes */
blockquote {
    border-left: 4px solid var(--color-accent);
    padding-left: var(--space-md);
    margin-left: 0;
    color: var(--color-text-light);
    font-style: italic;
    background: var(--color-bg-light);
    border-radius: 0 4px 4px 0;
    padding: var(--space-md);
    margin-bottom: var(--space-md);
}

/* ========================================
   Tables
   ======================================== */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: var(--space-md);
}

th, td {
    padding: var(--space-sm) var(--space-md);
    border: 1px solid var(--color-border);
    text-align: left;
}

th {
    background: var(--color-bg-light);
    font-weight: 600;
}

/* ========================================
   Images
   ======================================== */
img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: var(--space-xl) auto var(--space-xl);
}

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-block;
    padding: var(--space-sm) var(--space-md);
    background: var(--color-accent);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: background var(--transition-fast);
}

.btn:hover {
    background: var(--color-accent-light);
}

/* ========================================
   Utility Classes
   ======================================== */

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-xs { margin-top: var(--space-xs); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-xs { margin-bottom: var(--space-xs); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

/* ========================================
   Mobile-First Responsive Design
   ======================================== */

/* Small screens (default - mobile) */
@media (min-width: 600px) {
    html {
        font-size: 17px;
    }
}

/* Tablet - Show desktop navigation */
@media (min-width: 768px) {
    .nav-toggle {
        display: none;
    }

    .nav-menu {
        display: none;
    }

    .nav-overlay {
        display: none;
    }

    .header-nav {
        display: block;
        background: var(--color-bg);
        box-shadow: var(--shadow-sm);
        border-bottom: 1px solid var(--color-border);
    }

    .header-nav nav {
        display: flex;
        justify-content: center;
        align-items: center;
        max-width: var(--max-width);
        margin: 0 auto;
        padding: 0 var(--space-md);
        height: var(--nav-height);
    }

    .header-nav nav ul {
        display: flex;
        list-style: none;
        margin: 0;
        padding: 0;
        gap: var(--space-lg);
        align-items: center;
    }

    .header-nav nav a {
        color: var(--color-text);
        font-size: 1rem;
    }

    .header-nav nav a:hover {
        color: var(--color-accent);
    }

    .header-nav nav a.nav-home {
        font-size: 1.6rem;
        font-weight: 700;
        color: var(--color-logo);
    }

    .header-nav nav a.nav-home:hover {
        text-decoration: none;
        color: var(--color-logo-light);
    }

    main {
        padding: var(--space-xl) 0;
    }

    section {
        margin-bottom: var(--space-xl);
    }

    /* Adjust max width for better readability */
    .container {
        max-width: 1000px;
    }

    h1 { font-size: 2.4rem; }
    h2 { font-size: 1.4rem; }
    h3 { font-size: 1.2rem; }
}

/* Desktop */
@media (min-width: 1024px) {
    html {
        font-size: 18px;
    }

    .container {
        padding: 0 var(--space-xl);
    }

    .header-nav nav {
        padding: 0 var(--space-xl);
    }

    .header-nav nav ul {
        gap: var(--space-xl);
    }
}

/* ========================================
   Print Styles
   ======================================== */
@media print {
    .nav-toggle,
    .nav-menu,
    .nav-overlay,
    .header-nav,
    .sidebar,
    footer {
        display: none !important;
    }

    body {
        font-size: 12pt;
    }

    main {
        max-width: 100%;
        padding: 0;
    }

    a::after {
        content: " (" attr(href) ")";
        font-size: 0.8em;
        color: #666;
    }
}

/* ========================================
   Accessibility Enhancements
   ======================================== */

/* Focus styles */
:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}

/* High contrast mode */
@media (prefers-contrast: more) {
    :root {
        --color-text: #000;
        --color-bg: #fff;
        --color-border: #000;
    }

    a {
        text-decoration: underline;
    }
}

/* ========================================
   Dark Mode
   Automatically switches based on system preference
   ======================================== */
@media (prefers-color-scheme: dark) {
    :root {
        /* Dark background */
        --color-bg: #121212;
        --color-bg-light: #1e1e1e;

        /* Light text for dark mode */
        --color-text: #e0e0e0;
        --color-text-light: #b0b0b0;
        --color-text-lighter: #8a8a8a;

        /* Lighter borders */
        --color-border: #333333;
        --color-border-light: #2a2a2a;

        /* Adjusted code block colors */
        --color-code-bg: #2d2d2d;
        --color-code-border: #404040;
        --color-code-text: #e0e0e0;
    }

    /* Dark mode adjustments for specific elements */
    body {
        background-color: var(--color-bg);
    }

    main {
        background-color: var(--color-bg);
    }

    .container {
        background-color: var(--color-bg);
    }

    /* Navigation on dark mode */
    .header-nav {
        background-color: var(--color-bg);
        box-shadow: none;
        border-bottom: 1px solid var(--color-border);
    }

    .header-nav nav a {
        color: var(--color-text);
    }

    .header-nav nav a.nav-home {
        color: var(--color-accent);
    }

    /* Mobile navigation on dark mode */
    .mobile-header {
        background-color: var(--color-bg);
        border-bottom-color: var(--color-border);
    }

    .mobile-header a.nav-home {
        color: var(--color-accent);
    }

    .nav-menu {
        background-color: var(--color-primary);
    }

    .nav-menu a {
        color: white;
    }

    /* Page content on dark mode */
    h1, h2, h3, h4, h5, h6 {
        color: var(--color-text);
    }

    a {
        color: var(--color-accent-light);
    }

    a:hover {
        color: var(--color-accent);
    }

    /* Footer on dark mode */
    footer {
        background-color: var(--color-bg);
        border-top-color: var(--color-border);
        color: var(--color-text-light);
    }

    /* Blockquotes on dark mode */
    blockquote {
        background-color: var(--color-bg-light);
        border-left-color: var(--color-accent);
        color: var(--color-text-light);
    }

    /* Code blocks on dark mode */
    pre {
        background-color: var(--color-code-bg);
        border-color: var(--color-code-border);
        color: var(--color-code-text);
    }

    code {
        background-color: var(--color-code-bg);
        color: var(--color-code-text);
    }

    /* Tables on dark mode */
    table {
        background-color: var(--color-bg-light);
    }

    th, td {
        border-color: var(--color-border);
    }

    th {
        background-color: var(--color-bg);
        color: var(--color-text);
    }
}