/**
 * Aura Minimalist Main Stylesheet
 * Establishes a modern, premium design system for typography, sidebars, and responsiveness.
 */

/* ----------------------------------------------------
   1. Design System & CSS Custom Properties
---------------------------------------------------- */
:root {
    /* Color Palette */
    --primary-color: #1a73e8;       /* Accent Google Blue */
    --primary-hover: #1557b0;
    --text-main: #1f2937;           /* Deep Charcoal for high readability */
    --text-muted: #5f6368;          /* Soft Gray for secondary text/meta */
    --text-light: #9ca3af;
    --bg-main: #ffffff;
    --bg-secondary: #f8f9fa;        /* Light grey for cards and sidebars */
    --border-color: #dadce0;        /* Light clean border lines */
    --border-light: #f1f3f4;
    
    /* Typography */
    --font-body: 'Google Sans', 'Product Sans', 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-heading: 'Google Sans', 'Product Sans', 'Outfit', var(--font-body);
    
    /* Layout Spacing */
    --container-max-width: 1240px;
    --header-height: 70px;
    
    /* Transition & Shadows */
    --transition-smooth: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-subtle: 0 1px 2px 0 rgba(60,64,67,0.3), 0 1px 3px 1px rgba(60,64,67,0.15);
    --shadow-premium: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-hover: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.04);
}

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

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.625;
    color: var(--text-main);
    background-color: var(--bg-main);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition-smooth);
}

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

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

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--text-main);
    font-weight: 600;
    line-height: 1.25;
    margin-bottom: 0.5em;
}

/* Screen Reader Text utility */
.screen-reader-text {
    border: 0;
    clip: rect(1px, 1px, 1px, 1px);
    clip-path: inset(50%);
    height: 1px;
    margin: -1px;
    overflow: hidden;
    padding: 0;
    position: absolute;
    width: 1px;
    word-wrap: normal !important;
}

/* ----------------------------------------------------
   3. Theme Layout Structure (3-Column / 2-Column Grid)
---------------------------------------------------- */
.content-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 40px 24px;
    display: grid;
    gap: 48px;
    align-items: start;
}

/* Layout: Left Sidebar + Content + Right Sidebar */
.layout-three-columns {
    grid-template-columns: 220px 1fr 280px;
}

/* Layout: Content + Right Sidebar */
.layout-two-columns {
    grid-template-columns: 1fr 280px;
}

.main-content {
    min-width: 0; /* Prevents flex/grid overflow items */
}

/* ----------------------------------------------------
   4. Site Header (Sticky & Blurred Glassmorphic)
---------------------------------------------------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-light);
    height: var(--header-height);
    display: flex;
    align-items: center;
    transition: var(--transition-smooth);
}

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

.site-branding .site-title {
    font-size: 22px;
    font-weight: 700;
    margin: 0;
}

.site-branding .site-title a {
    color: var(--text-main);
}

.site-branding .site-description {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 2px;
}

/* Navigation Links */
.main-navigation ul {
    list-style: none;
    display: flex;
    gap: 28px;
}

.main-navigation li a {
    color: var(--text-muted);
    font-family: var(--font-heading);
    font-weight: 500;
    font-size: 15px;
    padding: 6px 0;
    position: relative;
}

.main-navigation li a:hover,
.main-navigation li.current-menu-item a {
    color: var(--text-main);
}

/* Underline slide effect on hover */
.main-navigation li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition-smooth);
}

.main-navigation li a:hover::after,
.main-navigation li.current-menu-item a::after {
    width: 100%;
}

/* Mobile Hamburger Menu (Hidden on Desktop) */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.menu-toggle .icon-bar {
    display: block;
    width: 22px;
    height: 2px;
    background-color: var(--text-main);
    margin: 4px 0;
    transition: var(--transition-smooth);
}

/* ----------------------------------------------------
   5. Left Sidebar (Dynamic Table of Contents)
---------------------------------------------------- */
.sidebar-left {
    position: sticky;
    top: calc(var(--header-height) + 40px);
    max-height: calc(100vh - var(--header-height) - 60px);
    overflow-y: auto;
    padding-right: 12px;
}

/* Scrollbar styling for TOC */
.sidebar-left::-webkit-scrollbar {
    width: 4px;
}
.sidebar-left::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.toc-sticky-wrapper .toc-title {
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-main);
    margin-bottom: 16px;
    font-weight: 700;
}

/* TOC List Structure */
.toc-navigation ul.toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
    border-left: 1px solid var(--border-color);
}

.toc-item {
    position: relative;
    padding: 6px 0 6px 16px;
    margin: 4px 0;
    line-height: 1.4;
}

.toc-item a {
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 400;
    display: block;
    transition: var(--transition-smooth);
}

.toc-item a:hover {
    color: var(--text-main);
}

/* Indent H3 sub-headings */
.toc-item-h3 {
    padding-left: 28px;
}

/* Active Class Styling - MATCHING REFERENCED IMAGE */
.toc-item.active a {
    color: var(--primary-color);
    font-weight: 500;
}

/* Active vertical indicator line positioned exactly over the border */
.toc-item.active::before {
    content: '';
    position: absolute;
    left: -1px; /* Align precisely over the light gray ul border */
    top: 0;
    bottom: 0;
    width: 2.5px;
    background-color: var(--primary-color);
    border-radius: 4px;
}

/* Placeholder skeleton loader */
.toc-placeholder {
    padding-left: 16px;
    border-left: 1px solid var(--border-color);
}
.toc-placeholder-line {
    display: block;
    height: 10px;
    background-color: var(--border-light);
    margin-bottom: 12px;
    border-radius: 2px;
    width: 80%;
}
.toc-placeholder-line:nth-child(2) { width: 60%; }
.toc-placeholder-line:nth-child(3) { width: 70%; }

/* ----------------------------------------------------
   6. Right Sidebar (Widgets)
---------------------------------------------------- */
.sidebar-right {
    position: sticky;
    top: calc(var(--header-height) + 40px);
    max-height: calc(100vh - var(--header-height) - 60px);
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 32px;
    padding-right: 4px;
}

/* Scrollbar styling for right sidebar */
.sidebar-right::-webkit-scrollbar {
    width: 4px;
}
.sidebar-right::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.widget {
    background-color: var(--bg-main);
    border: 1px solid var(--border-light);
    border-radius: 8px;
    padding: 24px;
    box-shadow: var(--shadow-premium);
    transition: var(--transition-smooth);
}

.widget:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
}

.widget-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1.5px solid var(--border-light);
}

/* Widget Search Form */
.search-form {
    display: flex;
    width: 100%;
}

.search-field {
    flex-grow: 1;
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-right: none;
    border-radius: 6px 0 0 6px;
    font-family: var(--font-body);
    font-size: 14px;
    outline: none;
    transition: var(--transition-smooth);
}

.search-field:focus {
    border-color: var(--primary-color);
}

.search-submit {
    background-color: var(--primary-color);
    color: #ffffff;
    border: none;
    padding: 10px 18px;
    font-family: var(--font-heading);
    font-weight: 500;
    font-size: 14px;
    border-radius: 0 6px 6px 0;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.search-submit:hover {
    background-color: var(--primary-hover);
}

/* Widget Lists (Recent Posts, Categories, Archives) */
.widget ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.widget ul li {
    padding: 8px 0;
    border-bottom: 1px solid var(--border-light);
    font-size: 14px;
}

.widget ul li:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.widget ul li a {
    color: var(--text-muted);
}

.widget ul li a:hover {
    color: var(--primary-color);
    padding-left: 4px;
}

/* ----------------------------------------------------
   7. Single Post Content Layout & Typography (Medium-style)
---------------------------------------------------- */
.single-post-article {
    background: var(--bg-main);
}

.entry-header {
    margin-bottom: 28px;
}

.entry-category a {
    font-family: var(--font-heading);
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    background-color: var(--border-light);
    color: var(--primary-color);
    padding: 4px 10px;
    border-radius: 4px;
    display: inline-block;
    margin-bottom: 12px;
}

.entry-title {
    font-size: 40px;
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.15;
    margin-bottom: 16px;
}

.entry-meta {
    font-size: 14px;
    color: var(--text-muted);
    display: flex;
    gap: 12px;
    align-items: center;
    border-bottom: 1px solid var(--border-light);
    padding-bottom: 16px;
}

.entry-meta .author-name {
    font-weight: 500;
    color: var(--text-main);
}

.post-thumbnail {
    margin: 32px 0;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-premium);
}

/* Premium Typography for Post Content */
.entry-content {
    font-size: 17px;
    line-height: 1.75;
    color: var(--text-main);
}

.entry-content p {
    margin-bottom: 24px;
}

.entry-content h2 {
    font-size: 28px;
    font-weight: 700;
    margin-top: 48px;
    margin-bottom: 18px;
    letter-spacing: -0.015em;
}

.entry-content h3 {
    font-size: 22px;
    font-weight: 600;
    margin-top: 36px;
    margin-bottom: 14px;
    letter-spacing: -0.01em;
}

/* Blockquotes styled elegantly */
.entry-content blockquote {
    font-style: italic;
    font-size: 1.15em;
    color: var(--text-muted);
    border-left: 3px solid var(--primary-color);
    padding-left: 20px;
    margin: 36px 0;
}

/* Code & Preformatted */
.entry-content pre {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-light);
    border-radius: 8px;
    padding: 20px;
    overflow-x: auto;
    font-family: monospace, monospace;
    font-size: 14px;
    margin-bottom: 24px;
}

.entry-content code {
    background-color: var(--bg-secondary);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.9em;
}

.entry-content pre code {
    padding: 0;
    background-color: transparent;
    border-radius: 0;
    font-size: inherit;
}

/* Page Navigation */
.post-navigation {
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    padding: 24px 0;
    margin: 48px 0;
    display: flex;
    justify-content: space-between;
    gap: 20px;
}

.post-navigation .nav-links {
    display: flex;
    justify-content: space-between;
    width: 100%;
}

.post-navigation .nav-previous,
.post-navigation .nav-next {
    flex: 1;
}

.post-navigation .nav-next {
    text-align: right;
}

.post-navigation .nav-subtitle {
    display: block;
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-light);
    margin-bottom: 4px;
}

.post-navigation .nav-title {
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 600;
    color: var(--text-main);
}

.post-navigation .nav-title:hover {
    color: var(--primary-color);
}

/* ----------------------------------------------------
   8. Blog Listing / Grid Cards (Index page)
---------------------------------------------------- */
.posts-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
}

.post-card {
    background: var(--bg-main);
    border: 1px solid var(--border-light);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-premium);
    transition: var(--transition-smooth);
    display: flex;
    flex-direction: column;
}

.post-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.post-card-thumbnail img {
    width: 100%;
    height: 240px;
    object-fit: cover;
    transition: var(--transition-smooth);
}

.post-card:hover .post-card-thumbnail img {
    scale: 1.02;
}

.post-card-content {
    padding: 28px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.post-card-category a {
    font-family: var(--font-heading);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary-color);
}

.post-card-title {
    font-size: 24px;
    font-weight: 700;
    margin: 8px 0 12px 0;
    line-height: 1.3;
}

.post-card-title a {
    color: var(--text-main);
}

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

.post-card-meta-bottom {
    font-size: 12px;
    color: var(--text-light);
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 16px;
}

.post-card-meta-bottom .post-card-author {
    color: var(--text-muted);
}

.post-card-excerpt {
    font-size: 15px;
    color: var(--text-muted);
    margin-bottom: 20px;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.post-card-footer {
    margin-top: auto;
}

.read-more-link {
    font-family: var(--font-heading);
    font-size: 14px;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.read-more-link .arrow {
    transition: var(--transition-smooth);
}

.read-more-link:hover .arrow {
    transform: translateX(4px);
}

/* Archive Pagination styling */
.navigation.pagination {
    margin-top: 48px;
    border-top: 1px solid var(--border-light);
    padding-top: 24px;
}

.navigation.pagination .nav-links {
    display: flex;
    justify-content: space-between;
}

.navigation.pagination .page-numbers {
    font-family: var(--font-heading);
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 4px;
    color: var(--text-muted);
    border: 1px solid transparent;
}

.navigation.pagination .page-numbers:hover,
.navigation.pagination .page-numbers.current {
    background-color: var(--border-light);
    color: var(--text-main);
    border-color: var(--border-color);
}

/* ----------------------------------------------------
   9. Footer Styles
---------------------------------------------------- */
.site-footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-light);
    padding: 40px 24px;
    margin-top: 80px;
}

.footer-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    display: flex;
    justify-content: center;
    text-align: center;
}

.site-info {
    font-size: 14px;
    color: var(--text-muted);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.site-info a {
    color: var(--text-main);
    font-weight: 500;
}

.site-info .heart {
    color: #e25555;
    display: inline-block;
    animation: heartbeat 1.5s infinite;
}

@keyframes heartbeat {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.15); }
}

/* ----------------------------------------------------
   10. Responsiveness & Breakpoints
---------------------------------------------------- */

/* Laptop screens (< 1024px) - TOC goes to 2-Column layout */
@media (max-width: 1024px) {
    .layout-three-columns {
        grid-template-columns: 1fr 260px; /* Hide left column, shift right sidebar */
    }
    
    .sidebar-left {
        display: none; /* TOC hidden or can be toggled; for simplicity, hidden on narrow screens */
    }
}

/* Tablet screens (< 768px) - Both sidebars stack */
@media (max-width: 768px) {
    .layout-three-columns,
    .layout-two-columns {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    
    .sidebar-right {
        margin-top: 16px;
    }

    .entry-title {
        font-size: 32px;
    }

    /* Mobile Header Navigation Menu */
    .menu-toggle {
        display: block;
    }

    .main-navigation {
        position: relative;
    }

    .nav-menu-wrapper {
        display: none; /* Hidden by default */
        position: absolute;
        top: 100%;
        right: 0;
        width: 240px;
        background-color: var(--bg-main);
        border: 1px solid var(--border-light);
        border-radius: 8px;
        box-shadow: var(--shadow-hover);
        padding: 16px;
        margin-top: 12px;
    }

    .main-navigation.toggled .nav-menu-wrapper {
        display: block;
    }

    .main-navigation ul {
        flex-direction: column;
        gap: 16px;
    }

    .main-navigation li a {
        display: block;
        padding: 4px 0;
    }

    /* Hamburger menu toggle states */
    .main-navigation.toggled .menu-toggle .icon-bar:nth-child(1) {
        transform: translateY(6px) rotate(45deg);
    }
    .main-navigation.toggled .menu-toggle .icon-bar:nth-child(2) {
        opacity: 0;
    }
    .main-navigation.toggled .menu-toggle .icon-bar:nth-child(3) {
        transform: translateY(-6px) rotate(-45deg);
    }
}

/* Phone screens (< 480px) */
@media (max-width: 480px) {
    .content-container {
        padding: 24px 16px;
    }
    
    .entry-title {
        font-size: 26px;
    }
    
    .entry-content {
        font-size: 16px;
    }
}