/* ============================================
   CSS Custom Properties (Variables)
   ============================================ */
:root {
    /* Colors - Light theme */
    --color-bg: #ffffff;
    --color-text: #222222;
    --color-text-muted: #666666;
    --color-link: #0066cc;
    --color-link-hover: #0052a3;
    --color-border: #e0e0e0;
    --color-accent: #0066cc;
    --color-surface: #f8f8f8;
    --color-sidebar-bg: #fafafa;
    --color-code-bg: #f5f5f5;
    --color-code-border: #e0e0e0;

    /* Typography - Compact */
    --font-base:
        -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
        Arial, sans-serif;
    --font-mono:
        "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
    --font-size-base: 16px;
    --line-height-base: 1.5;
    --line-height-tight: 1.2;

    /* Spacing - Compact */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 0.75rem;
    --space-lg: 1rem;
    --space-xl: 1.5rem;
    --space-xxl: 2rem;

    /* Layout - Two column */
    --sidebar-width: 220px;
    --content-max-width: 1200px;
}

/* ============================================
   Dark Theme (Auto-detects system preference)
   ============================================ */
@media (prefers-color-scheme: dark) {
    :root {
        /* Colors - Dark theme */
        --color-bg: #1a1a1a;
        --color-text: #e4e4e4;
        --color-text-muted: #a0a0a0;
        --color-link: #5c9fd8;
        --color-link-hover: #7eb3e3;
        --color-border: #3a3a3a;
        --color-accent: #5c9fd8;
        --color-surface: #242424;
        --color-sidebar-bg: #1f1f1f;
        --color-code-bg: #2a2a2a;
        --color-code-border: #3a3a3a;
    }

    /* Reduce image brightness in dark mode */
    img {
        opacity: 0.9;
    }

    img:hover {
        opacity: 1;
    }

    /* Ensure skip link is visible in dark mode */
    .skip-link {
        background: var(--color-accent);
        color: var(--color-bg);
    }
}

/* ============================================
   Reset and Base Styles
   ============================================ */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    font-size: var(--font-size-base);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    margin: 0;
    font-family: var(--font-base);
    line-height: var(--line-height-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    color-scheme: light dark;
}

/* ============================================
   Skip Link (Accessibility)
   ============================================ */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--color-accent);
    color: white;
    padding: var(--space-sm);
    text-decoration: none;
    z-index: 100;
}

.skip-link:focus {
    top: 0;
}

/* ============================================
   Typography
   ============================================ */
h1,
h2,
h3,
h4,
h5,
h6 {
    margin: var(--space-lg) 0 var(--space-sm);
    line-height: var(--line-height-tight);
    font-weight: 600;
}

h1 {
    font-size: 1.75rem;
}
h2 {
    font-size: 1.5rem;
}
h3 {
    font-size: 1.25rem;
}
h4 {
    font-size: 1.1rem;
}
h5 {
    font-size: 1rem;
}
h6 {
    font-size: 0.95rem;
}

p {
    margin: 0 0 var(--space-md);
}

a {
    color: var(--color-link);
    text-decoration: underline;
    text-decoration-color: transparent;
    text-underline-offset: 2px;
    transition: text-decoration-color 0.2s;
}

a:hover {
    color: var(--color-link-hover);
    text-decoration-color: var(--color-link-hover);
}

a:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background: var(--color-code-bg);
    padding: 0.2em 0.4em;
    border-radius: 3px;
}

pre {
    overflow-x: auto;
    padding: var(--space-md);
    background: var(--color-code-bg);
    border: 1px solid var(--color-code-border);
    border-radius: 4px;
}

pre code {
    background: none;
    padding: 0;
}

blockquote {
    margin: var(--space-md) 0;
    padding-left: var(--space-md);
    border-left: 4px solid var(--color-accent);
    color: var(--color-text-muted);
    font-style: italic;
}

/* ============================================
   Site Container and Layout
   ============================================ */
.site-container {
    max-width: var(--content-max-width);
    margin: 0 auto;
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr var(--sidebar-width);
    gap: var(--space-xl);
    padding: 0 var(--space-lg);
    min-height: calc(100vh - 200px);
}

/* ============================================
   Header
   ============================================ */
.site-header {
    background: transparent;
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-lg) var(--space-lg);
}

.site-branding a {
    text-decoration: none;
}

.site-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-text);
    margin: 0;
}

.site-tagline {
    margin: var(--space-xs) 0 0;
    color: var(--color-text-muted);
    font-size: 0.875rem;
    font-weight: 400;
}

/* ============================================
   Sidebar
   ============================================ */
.sidebar {
    background: transparent;
    padding: var(--space-lg);
    border-left: 1px solid var(--color-border);
    position: sticky;
    top: var(--space-lg);
    align-self: start;
    max-height: calc(100vh - 2rem);
    overflow-y: auto;
}

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

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

.sidebar-nav a {
    display: block;
    padding: var(--space-xs) 0;
    color: var(--color-text);
    text-decoration: none;
    font-size: 0.9rem;
}

.sidebar-nav a:hover {
    color: var(--color-link);
}

.sidebar-nav a[aria-current="page"] {
    color: var(--color-link);
    font-weight: 600;
}

.sidebar-section {
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.sidebar-section h3 {
    margin: 0 0 var(--space-md);
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.tag-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.tag-link {
    display: block;
    padding: var(--space-xs) 0;
    font-size: 0.85rem;
    color: var(--color-text);
    text-decoration: none;
}

.tag-link:hover {
    color: var(--color-link);
}

.tag-link .tag-count {
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

/* ============================================
   Main Content
   ============================================ */
main {
    min-width: 0; /* Prevent grid blowout */
    padding: var(--space-lg) 0;
    max-width: 900px;
}

.article-header {
    margin-bottom: var(--space-lg);
}

.article-header h1 {
    margin: 0;
}

.article-content {
    max-width: 100%;
}

.article-content img {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
}

.article-footer {
    margin-top: var(--space-xl);
    padding-top: var(--space-md);
}

.tags {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

.tags li a {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 20px;
    font-size: 0.85rem;
    transition: background-color 0.2s;
}

.tags li a:hover {
    background: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
}

/* ============================================
   Home Page
   ============================================ */
.home-intro {
    margin-bottom: var(--space-xl);
}

.home-intro h1 {
    margin-top: 0;
}

/* ============================================
   List Pages
   ============================================ */
.list-header {
    margin-bottom: var(--space-xl);
}

.list-header h1 {
    margin-top: 0;
}

/* Date grouping */
.date-group {
    margin-bottom: var(--space-xl);
}

.group-date {
    display: block;
    color: var(--color-text-muted);
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
    letter-spacing: 0.02em;
    text-transform: uppercase;
}

/* List items */
.list-item {
    margin-bottom: var(--space-xxl);
    padding-bottom: var(--space-xl);
    border-bottom: 1px solid var(--color-border);
}

.list-item:last-child {
    border-bottom: none;
}

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

.list-item h2,
.list-item h3 {
    margin: 0 0 var(--space-xs);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
}

.list-item .article-content {
    margin-top: var(--space-md);
}

.list-item .article-content h2 {
    font-size: 1.1rem;
    margin-top: var(--space-lg);
}

.list-item .article-content h3 {
    font-size: 1rem;
    margin-top: var(--space-md);
}

/* Post metadata */
.post-meta {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-top: var(--space-md);
}

.post-meta a {
    color: var(--color-text-muted);
}

.post-meta a:hover {
    color: var(--color-link);
}

.permalink {
    text-decoration: none;
    font-weight: 600;
    margin-right: 0.5rem;
}

.post-meta time {
    color: var(--color-text-muted);
}

.meta-separator {
    margin: 0 0.5rem;
    color: var(--color-text-muted);
}

/* ============================================
   Pagination
   ============================================ */
.pagination {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: var(--space-xxl);
    padding-top: var(--space-lg);
}

.pagination-prev,
.pagination-next {
    font-size: 1rem;
    color: var(--color-link);
    text-decoration: none;
    padding: var(--space-xs) var(--space-sm);
}

.pagination-prev:hover,
.pagination-next:hover {
    color: var(--color-link-hover);
    text-decoration: none;
}

.pagination-info {
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

/* Center the info when only one pagination link exists */
.pagination:has(.pagination-prev):not(:has(.pagination-next)) .pagination-info {
    margin-left: auto;
}

.pagination:has(.pagination-next):not(:has(.pagination-prev)) .pagination-info {
    margin-right: auto;
}

/* ============================================
   Highlights Section
   ============================================ */
.highlights {
    margin-bottom: var(--space-xl);
    padding: var(--space-lg);
    background: var(--color-surface);
    border-radius: 4px;
    border: 1px solid var(--color-border);
}

.highlights h2 {
    margin-top: 0;
    margin-bottom: var(--space-md);
    font-size: 1.1rem;
}

.highlights-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

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

.highlights-list time {
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

/* Tag cloud styles removed - now in sidebar */

/* ============================================
   Year Archives
   ============================================ */
.archive-years {
    margin-bottom: var(--space-md);
    font-size: 0.875rem;
}

.archive-label {
    color: var(--color-text-muted);
    margin-right: var(--space-sm);
}

.archive-years a {
    margin-right: var(--space-sm);
}

.archive-count {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--space-lg);
}

/* Tag description */
.tag-description {
    color: var(--color-text);
    line-height: var(--line-height-base);
    margin-bottom: var(--space-lg);
    padding: var(--space-md);
    background: var(--color-surface);
    border-left: 3px solid var(--color-accent);
    border-radius: 4px;
}

.tag-description p {
    margin: 0;
}

.archives-index {
    max-width: 600px;
}

.archive-year-item {
    margin-bottom: var(--space-lg);
}

.archive-year-item h2 {
    margin: 0;
    font-size: 1.75rem;
}

.archive-year-item h2 a {
    color: var(--color-text);
    text-decoration: none;
}

.archive-year-item h2 a:hover {
    color: var(--color-link);
}

.post-count {
    font-size: 0.875rem;
    font-weight: 400;
    color: var(--color-text-muted);
    margin-left: 0.5rem;
}

/* ============================================
   Related Posts
   ============================================ */
.related-posts {
    margin-top: var(--space-xxl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.related-posts h2 {
    font-size: 1.25rem;
    margin-top: 0;
}

.related-posts ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.related-posts li {
    margin-bottom: var(--space-sm);
}

.related-posts time {
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

/* ============================================
   Article Meta (Single Posts)
   ============================================ */
/* Article meta styles removed - now using post-meta */

/* ============================================
   Footer
   ============================================ */
.site-footer {
    margin-top: var(--space-xl);
    padding: var(--space-lg);
    background: transparent;
    border-top: 1px solid var(--color-border);
    text-align: left;
    color: var(--color-text-muted);
}

.footer-content {
    padding: 0 var(--space-lg);
}

.footer-content p {
    margin: var(--space-xs) 0;
    font-size: 0.8rem;
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 900px) {
    :root {
        --font-size-base: 15px;
        --space-lg: 0.75rem;
        --space-xl: 1rem;
        --space-xxl: 1.5rem;
    }

    .content-wrapper {
        grid-template-columns: 1fr;
        gap: 0;
        padding: 0;
    }

    .sidebar {
        position: static;
        max-height: none;
        border-left: none;
        border-bottom: 1px solid var(--color-border);
        padding: var(--space-md);
    }

    .sidebar-nav {
        display: flex;
        flex-wrap: wrap;
        gap: var(--space-sm);
    }

    .sidebar-nav li {
        margin-bottom: 0;
    }

    .sidebar-section {
        margin-top: var(--space-md);
        padding-top: var(--space-md);
    }

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

    .site-header,
    .footer-content {
        padding: var(--space-md);
    }

    h1 {
        font-size: 1.5rem;
    }
    h2 {
        font-size: 1.3rem;
    }
}

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

/* ============================================
   Print Styles
   ============================================ */
@media print {
    /* Hide navigation and UI elements */
    .sidebar,
    .site-footer,
    .skip-link,
    .article-footer .tags,
    .related-posts,
    .highlights,
    .pagination,
    .archive-years {
        display: none !important;
    }

    /* Hide permalink in print but show date */
    .permalink {
        display: none !important;
    }

    .post-meta {
        display: block !important;
        margin-top: 0.5cm;
        padding-top: 0.3cm;
        border-top: 1px solid #ccc;
    }

    /* Reset layout to single column */
    body {
        font-size: 12pt;
        line-height: 1.5;
        color: #000;
        background: #fff;
    }

    .site-container {
        max-width: 100%;
    }

    .content-wrapper {
        display: block;
        padding: 0;
        gap: 0;
    }

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

    /* Simplify header for print */
    .site-header {
        border-bottom: 2px solid #000;
        padding: 0.5cm 0;
        margin-bottom: 1cm;
    }

    .site-title {
        font-size: 18pt;
        color: #000;
    }

    .site-tagline {
        font-size: 10pt;
        color: #666;
    }

    /* Optimize typography for print */
    h1 {
        font-size: 18pt;
        margin: 0.5cm 0 0.3cm;
        page-break-after: avoid;
    }

    h2 {
        font-size: 14pt;
        margin: 0.4cm 0 0.2cm;
        page-break-after: avoid;
    }

    h3 {
        font-size: 12pt;
        margin: 0.3cm 0 0.2cm;
        page-break-after: avoid;
    }

    h4,
    h5,
    h6 {
        font-size: 11pt;
        margin: 0.3cm 0 0.2cm;
        page-break-after: avoid;
    }

    p {
        margin: 0 0 0.3cm;
        orphans: 3;
        widows: 3;
    }

    .article-header h1 {
        margin-top: 0;
    }

    /* Handle links for print */
    a {
        color: #000;
        text-decoration: none;
    }

    a[href^="http"]:after {
        content: " (" attr(href) ")";
        font-size: 9pt;
        color: #666;
    }

    /* Don't show URLs for internal links */
    a[href^="/"]:after,
    a[href^="#"]:after {
        content: "";
    }

    /* Code blocks */
    pre,
    code {
        font-size: 9pt;
        background: #f5f5f5;
        border: 1px solid #ddd;
        page-break-inside: avoid;
    }

    pre {
        padding: 0.3cm;
        white-space: pre-wrap;
        word-wrap: break-word;
    }

    /* Images */
    img {
        max-width: 100%;
        page-break-inside: avoid;
    }

    /* List items */
    .list-item {
        margin-bottom: 0.5cm;
        page-break-inside: avoid;
    }

    .list-item h2 {
        font-size: 13pt;
    }

    /* Date grouping */
    .group-date {
        font-size: 10pt;
        font-weight: bold;
        margin: 0.4cm 0 0.2cm;
        border-bottom: 1px solid #ccc;
        padding-bottom: 0.1cm;
    }

    /* Prevent breaks */
    blockquote,
    table,
    figure {
        page-break-inside: avoid;
    }

    /* Table styles */
    table {
        border-collapse: collapse;
        width: 100%;
    }

    th,
    td {
        border: 1px solid #000;
        padding: 0.2cm;
        text-align: left;
    }
}