/* Design System Variables */
:root {
    /* Color Palette - Light Mode (Medium-Inspired Green & Neutral) */
    --bg-primary: #ffffff;
    --bg-secondary: #fafafa;
    --text-primary: #191919;
    --text-secondary: #6b6b6b;
    --text-muted: #9e9e9e;
    --accent: #1a8917; /* Medium Green */
    --accent-hover: #156512;
    --accent-light: #e8f5e9;
    --border-color: #f2f2f2;
    --card-bg: #ffffff;
    --code-bg: #f2f2f2;
    --code-text: #24292e;
    --header-bg: rgba(255, 255, 255, 0.85);
    --shadow-color: rgba(0, 0, 0, 0.04);
    --footer-bg: #191919;
    --footer-text: #ffffff;
    --transition-speed: 0.25s;
    
    /* Layout Constants */
    --max-width-feed: 1040px;
    --max-width-post: 680px;
}

/* Dark Mode Color Palette overrides */
[data-theme="dark"] {
    --bg-primary: #0b0b0c;
    --bg-secondary: #121214;
    --text-primary: #f5f5f7;
    --text-secondary: #a0a0a8;
    --text-muted: #6e6e73;
    --accent: #24a820;
    --accent-hover: #1c8819;
    --accent-light: #162a15;
    --border-color: #1c1c1e;
    --card-bg: #121214;
    --code-bg: #1a1a1e;
    --code-text: #f5f5f7;
    --header-bg: rgba(11, 11, 12, 0.85);
    --shadow-color: rgba(0, 0, 0, 0.4);
    --footer-bg: #0b0b0c;
    --footer-text: #a0a0a8;
}

/* Global Reset & Base Styles */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-speed), color var(--transition-speed);
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-speed);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    transition: all var(--transition-speed);
}

/* ---------------------------------------------------- */
/* Scroll Progress Indicator                           */
/* ---------------------------------------------------- */
#progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--accent);
    transform-origin: 0 50%;
    transform: scaleX(0);
    z-index: 1000;
}

/* Modern native CSS scroll-driven progress (if supported) */
@media (prefers-reduced-motion: no-preference) {
    @supports (animation-timeline: scroll()) {
        @keyframes grow-progress {
            from { transform: scaleX(0); }
            to { transform: scaleX(1); }
        }
        
        #progress {
            animation: grow-progress auto linear;
            animation-timeline: scroll();
        }
    }
}

/* ---------------------------------------------------- */
/* Header Navigation                                   */
/* ---------------------------------------------------- */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 65px;
    background-color: var(--header-bg);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 900;
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.header-container {
    max-width: var(--max-width-feed);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-logo {
    font-size: 1.35rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    color: var(--text-primary);
}

.logo-accent {
    color: var(--accent);
    margin-right: 2px;
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.nav-link:hover {
    color: var(--text-primary);
}

.nav-divider {
    width: 1px;
    height: 16px;
    background-color: var(--border-color);
}

.theme-toggle {
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6px;
    border-radius: 50%;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
}

.theme-toggle:hover {
    color: var(--text-primary);
    background-color: var(--border-color);
}

.theme-toggle .moon-icon {
    display: block;
}
.theme-toggle .sun-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: none;
}
[data-theme="dark"] .theme-toggle .sun-icon {
    display: block;
}

/* ---------------------------------------------------- */
/* Main Content Layout                                 */
/* ---------------------------------------------------- */
.main-content {
    margin-top: 65px; /* offset header height */
    min-height: calc(100vh - 65px - 160px); /* fill screen minus header & footer */
    padding: 40px 0;
}

/* ---------------------------------------------------- */
/* Homepage Styles                                     */
/* ---------------------------------------------------- */
.homepage-container {
    max-width: var(--max-width-feed);
    margin: 0 auto;
    padding: 0 24px;
}

/* Featured Section */
.featured-section {
    margin-bottom: 50px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 40px;
}

.featured-card {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    align-items: center;
}

.featured-image-link {
    display: block;
    border-radius: 6px;
    overflow: hidden;
    aspect-ratio: 16 / 9;
    box-shadow: 0 4px 20px var(--shadow-color);
    background-color: var(--bg-secondary);
}

.featured-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.featured-image-link:hover .featured-image {
    transform: scale(1.03);
}

.featured-image-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--accent-light), var(--bg-secondary));
    color: var(--accent);
    font-size: 4rem;
    font-weight: 800;
}

.featured-info {
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.post-meta-header {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.author-avatar-small {
    width: 22px;
    height: 22px;
    border-radius: 50%;
    object-fit: cover;
}

.author-avatar-text {
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background-color: var(--accent);
    color: #ffffff;
    font-weight: 600;
    font-size: 0.7rem;
    display: flex;
    align-items: center;
    justify-content: center;
    text-transform: uppercase;
}

.meta-author {
    font-weight: 600;
    color: var(--text-primary);
}

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

.featured-title {
    font-size: 2rem;
    font-weight: 800;
    line-height: 1.25;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
    color: var(--text-primary);
}

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

.featured-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.post-meta-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: auto;
}

.post-tags-container {
    display: flex;
    gap: 8px;
}

.post-tag {
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    padding: 4px 10px;
    border-radius: 100px;
    font-weight: 500;
    border: 1px solid var(--border-color);
}

.post-tag:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
}

/* Feed and Sidebar layout */
.feed-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
}

.section-title {
    font-size: 1.2rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-primary);
    margin-bottom: 24px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
}

.posts-list {
    display: flex;
    flex-direction: column;
    gap: 36px;
}

.post-card {
    display: grid;
    grid-template-columns: 1fr 150px;
    gap: 24px;
    padding-bottom: 30px;
    border-bottom: 1px solid var(--border-color);
    align-items: flex-start;
}

.post-card-content {
    display: flex;
    flex-direction: column;
}

.post-title {
    font-size: 1.4rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 8px;
    letter-spacing: -0.2px;
}

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

.post-desc {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.post-card-image-link {
    border-radius: 4px;
    overflow: hidden;
    aspect-ratio: 4 / 3;
    background-color: var(--bg-secondary);
}

.post-card-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.post-card-image-link:hover .post-card-image {
    transform: scale(1.05);
}

/* Sidebar Widgets */
.feed-sidebar {
    display: flex;
    flex-direction: column;
    gap: 40px;
    position: sticky;
    top: 105px;
    height: fit-content;
}

.sidebar-widget {
    background-color: var(--bg-primary);
}

.sidebar-title {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.sidebar-about-text {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.tag-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.cloud-tag {
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
    padding: 6px 12px;
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 500;
}

.cloud-tag:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
}

/* Empty & Feed info states */
.empty-state {
    padding: 60px 40px;
    text-align: center;
    border: 1px dashed var(--border-color);
    border-radius: 8px;
    margin: 40px 0;
}

.empty-state h2 {
    margin-bottom: 12px;
}

.empty-state code {
    background-color: var(--code-bg);
    padding: 3px 6px;
    border-radius: 4px;
    font-size: 0.9rem;
}

.feed-info-text {
    color: var(--text-muted);
    font-style: italic;
    text-align: center;
    padding: 20px 0;
}

/* ---------------------------------------------------- */
/* Post Detail / Article Styles                        */
/* ---------------------------------------------------- */
.post-detail-container {
    max-width: var(--max-width-feed);
    margin: 0 auto;
    padding: 0 24px;
}

.post-detail-header {
    max-width: var(--max-width-post);
    margin: 0 auto 30px auto;
}

.post-detail-tags {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.post-detail-title {
    font-family: 'Inter', sans-serif;
    font-size: 2.75rem;
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -1.2px;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.post-detail-description {
    font-size: 1.35rem;
    line-height: 1.4;
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-weight: 400;
}

.post-detail-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
}

.author-avatar-medium {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    object-fit: cover;
}

.author-avatar-text-medium {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background-color: var(--accent);
    color: #ffffff;
    font-weight: 600;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    text-transform: uppercase;
}

.meta-details {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.meta-row {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}

.meta-author-name {
    font-weight: 600;
    color: var(--text-primary);
}

.follow-btn {
    font-size: 0.8rem;
    color: var(--accent);
    font-weight: 600;
}

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

.text-muted {
    color: var(--text-secondary);
}

.post-detail-cover {
    max-width: var(--max-width-feed);
    margin: 0 auto 50px auto;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 30px var(--shadow-color);
}

.cover-image {
    width: 100%;
    max-height: 600px;
    object-fit: cover;
}

/* Core typography for Reading View (Medium Typography) */
.post-detail-body {
    max-width: var(--max-width-post);
    margin: 0 auto;
}

.typography-serif {
    font-family: 'Lora', Georgia, Cambria, "Times New Roman", Times, serif;
    font-size: 1.25rem; /* ~20px */
    line-height: 1.8;
    color: var(--text-primary);
}

.post-detail-body p {
    margin-bottom: 24px;
}

.post-detail-body h1,
.post-detail-body h2,
.post-detail-body h3,
.post-detail-body h4 {
    font-family: 'Inter', sans-serif;
    color: var(--text-primary);
    font-weight: 700;
    line-height: 1.3;
    margin-top: 40px;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.post-detail-body h1 { font-size: 2rem; }
.post-detail-body h2 { font-size: 1.7rem; }
.post-detail-body h3 { font-size: 1.4rem; }
.post-detail-body h4 { font-size: 1.2rem; }

/* Emphasis styles */
.post-detail-body strong {
    font-weight: 700;
}

.post-detail-body blockquote {
    border-left: 3px solid var(--text-primary);
    padding-left: 20px;
    margin: 30px 0;
    font-style: italic;
    color: var(--text-secondary);
}

/* Lists */
.post-detail-body ul,
.post-detail-body ol {
    margin-bottom: 24px;
    padding-left: 24px;
}

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

/* Code block styles (Premium and custom dark themed) */
.post-detail-body pre {
    background-color: var(--code-bg);
    border-radius: 6px;
    padding: 16px 20px;
    margin: 30px 0;
    overflow-x: auto;
    border: 1px solid var(--border-color);
}

.post-detail-body code {
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    color: var(--code-text);
    background-color: var(--code-bg);
    padding: 3px 6px;
    border-radius: 4px;
}

.post-detail-body pre code {
    background-color: transparent;
    padding: 0;
    border-radius: 0;
    display: block;
    line-height: 1.5;
}

/* Inline markdown Tables */
.post-detail-body table {
    width: 100%;
    border-collapse: collapse;
    margin: 30px 0;
    font-family: 'Inter', sans-serif;
    font-size: 0.95rem;
}

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

.post-detail-body th {
    background-color: var(--bg-secondary);
    font-weight: 600;
}

.post-detail-body tr:nth-child(even) {
    background-color: var(--bg-secondary);
}

/* Images within article */
.post-detail-body img {
    margin: 36px 0;
    border-radius: 4px;
    box-shadow: 0 4px 12px var(--shadow-color);
}

/* Related articles grid */
.related-posts-section {
    border-top: 1px solid var(--border-color);
    margin-top: 60px;
    padding-top: 40px;
}

.related-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 24px;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.related-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.related-image-link {
    aspect-ratio: 16 / 9;
    overflow: hidden;
    display: block;
    background-color: var(--bg-secondary);
}

.related-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.related-image-link:hover .related-image {
    transform: scale(1.04);
}

.related-content {
    padding: 20px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.related-post-title {
    font-size: 1.15rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 8px;
    margin-top: 4px;
}

.related-post-title a:hover {
    color: var(--accent);
}

.related-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ---------------------------------------------------- */
/* Tag Page Styles                                      */
/* ---------------------------------------------------- */
.tag-page-container {
    max-width: 680px;
    margin: 0 auto;
    padding: 0 24px;
}

.tag-page-header {
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 30px;
    margin-bottom: 40px;
    text-align: center;
}

.tag-indicator {
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-muted);
    letter-spacing: 1.5px;
    display: block;
    margin-bottom: 8px;
}

.tag-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.tag-count {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

/* ---------------------------------------------------- */
/* Error Page Styles                                    */
/* ---------------------------------------------------- */
.error-page-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - 65px - 160px - 80px);
    padding: 24px;
}

.error-card {
    text-align: center;
    max-width: 480px;
}

.error-code {
    font-size: 6rem;
    font-weight: 800;
    color: var(--border-color);
    line-height: 1;
    margin-bottom: 10px;
}

.error-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.error-text {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.btn-primary {
    display: inline-block;
    background-color: var(--accent);
    color: #ffffff;
    padding: 10px 24px;
    border-radius: 100px;
    font-weight: 600;
    font-size: 0.95rem;
}

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

/* ---------------------------------------------------- */
/* Footer Styles                                       */
/* ---------------------------------------------------- */
.site-footer {
    background-color: var(--footer-bg);
    color: var(--footer-text);
    padding: 48px 0;
    border-top: 1px solid var(--border-color);
}

.footer-container {
    max-width: var(--max-width-feed);
    margin: 0 auto;
    padding: 0 24px;
}

.footer-info {
    margin-bottom: 30px;
}

.footer-logo {
    font-size: 1.2rem;
    font-weight: 800;
    color: #ffffff;
    display: block;
    margin-bottom: 8px;
}

.footer-tagline {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    font-size: 0.85rem;
    color: var(--text-muted);
}

.footer-socials {
    display: flex;
    gap: 16px;
}

.social-link {
    color: var(--text-muted);
}

.social-link:hover {
    color: #ffffff;
}

/* ---------------------------------------------------- */
/* Pagination Styles                                   */
/* ---------------------------------------------------- */
.pagination {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 50px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

.page-numbers {
    display: flex;
    gap: 8px;
    align-items: center;
}

.page-link {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
    padding: 8px 16px;
    border-radius: 100px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
}

.page-link:hover:not(.disabled) {
    background-color: var(--border-color);
    color: var(--accent-hover);
}

.page-link.disabled {
    color: var(--text-muted);
    border-color: var(--border-color);
    background-color: var(--bg-primary);
    cursor: not-allowed;
    opacity: 0.5;
}

.page-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.page-number:hover {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
}

.page-number.active {
    background-color: var(--accent);
    color: #ffffff;
    font-weight: 600;
}

/* ---------------------------------------------------- */
/* Responsive Adaptation                               */
/* ---------------------------------------------------- */
@media (max-width: 900px) {
    .featured-card {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .feed-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .feed-sidebar {
        position: static;
        top: 0;
    }
}

@media (max-width: 600px) {
    html {
        font-size: 15px;
    }
    
    .header-container {
        padding: 0 16px;
    }
    
    .main-content {
        padding: 24px 0;
    }
    
    .post-card {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .post-card-image-link {
        order: -1;
        aspect-ratio: 16 / 9;
    }
    
    .post-detail-title {
        font-size: 2rem;
    }
    
    .post-detail-description {
        font-size: 1.15rem;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        align-items: flex-start;
    }
}