:root {
    /* The "Academic Paper" Palette */
    --paper-bg: #F9F7F1;
    --ink-primary: #1A1A1A;
    --ink-secondary: #555555;
    --accent-blue: #003366;
    --accent-highlight: #E8E4D9;
    --border-color: #DCD6CC;

    /* Spacing */
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 2rem;
    --spacing-xl: 4rem;
}

body {
    margin: 0;
    background-color: var(--paper-bg);
    color: var(--ink-primary);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Merriweather', serif;
    color: var(--ink-primary);
    line-height: 1.3;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-top: var(--spacing-xl);
}

h3 {
    font-size: 1.35rem;
    font-weight: 700;
}

h4, h5, h6 {
    font-weight: 700;
}

p {
    margin-bottom: 24px;
    font-size: 1.05rem;
}

a {
    color: var(--accent-blue);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #002244;
}

/* Layout Container */
.container {
    max-width: 740px;
    margin: 0 auto;
    padding: 40px 24px;
}

/* Header */
header {
    margin-bottom: var(--spacing-xl);
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 0;
    padding-bottom: 0;
}

.brand {
    display: flex;
    align-items: center;
    gap: 16px;
    text-decoration: none;
    color: var(--ink-primary);
}

.brand-text {
    font-family: 'Merriweather', serif;
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.5px;
}

.brand-text span {
    color: var(--ink-secondary);
    font-weight: 300;
    font-style: italic;
    font-size: 1rem;
    margin-left: 6px;
}

.logo-ink {
    width: 42px;
    height: 42px;
}

/* Navigation */
nav {
    display: flex;
    gap: 24px;
}

nav a {
    text-decoration: none;
    color: var(--ink-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s;
}

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

nav a.nav-external {
    margin-left: 12px;
}

/* Remove top margin from first heading in main content */
main.container > h1:first-child {
    margin-top: 0;
}

/* Meta/Category label */
.meta {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--accent-blue);
    font-weight: 600;
    margin-bottom: 16px;
    display: block;
}

.subtitle {
    font-size: 1.25rem;
    color: var(--ink-secondary);
    font-weight: 400;
    margin-bottom: 40px;
}

/* Code Blocks */
pre, code {
    font-family: 'JetBrains Mono', monospace;
    background-color: var(--accent-highlight);
    border-radius: 4px;
}

code {
    padding: 0.2em 0.4em;
    font-size: 0.9em;
}

pre {
    padding: var(--spacing-md);
    overflow-x: auto;
    border: 1px solid var(--border-color);
}

pre code {
    padding: 0;
    font-size: 0.9em;
    background-color: transparent;
}

/* Tags */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin: var(--spacing-md) 0;
}

.tag {
    display: inline-block;
    background-color: var(--accent-highlight);
    color: var(--ink-secondary);
    padding: 0.25em 0.75em;
    border-radius: 4px;
    font-size: 0.85em;
    font-weight: 500;
    text-decoration: none;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.tag:hover {
    background-color: var(--accent-blue);
    color: white;
    border-color: var(--accent-blue);
}

.tag-overview {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
}

.tag-section {
    margin-bottom: var(--spacing-xl);
    padding-top: var(--spacing-md);
}

.tag-section h3 {
    margin-top: 0;
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--border-color);
}

.tag-posts {
    list-style: none;
    padding: 0;
}

.tag-posts li {
    padding: var(--spacing-sm) 0;
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.tag-posts .post-date {
    display: inline;
    margin: 0;
}

/* Post listing */
.post-listing {
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
}

.post-listing:last-child {
    border-bottom: none;
}

.post-listing h5 {
    font-family: 'Merriweather', serif;
    font-size: 1.35rem;
    margin: 0 0 8px 0;
}

.post-listing h5 a {
    color: var(--ink-primary);
}

.post-listing h5 a:hover {
    color: var(--accent-blue);
}

.post-date {
    display: block;
    color: var(--ink-secondary);
    font-size: 0.85rem;
    margin-bottom: var(--spacing-sm);
}

.post-listing .excerpt {
    margin-top: var(--spacing-sm);
    color: var(--ink-secondary);
    font-size: 1rem;
}

.post-listing .excerpt p {
    margin: 0;
}

/* Search */
.search-container {
    margin: var(--spacing-lg) 0;
}

#search-input {
    width: 100%;
    padding: 14px 18px;
    font-size: 1rem;
    font-family: 'Inter', sans-serif;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: white;
    color: var(--ink-primary);
    transition: border-color 0.2s, box-shadow 0.2s;
}

#search-input:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(0, 51, 102, 0.1);
}

#search-input::placeholder {
    color: var(--ink-secondary);
}

.search-results-list {
    list-style: none;
    padding: 0;
    margin-top: var(--spacing-lg);
}

.search-result-item {
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--border-color);
}

.search-result-item h3 {
    margin: 0 0 var(--spacing-sm) 0;
    font-size: 1.2rem;
}

.search-result-item a {
    text-decoration: none;
}

.search-result-item p {
    margin: var(--spacing-sm) 0 0 0;
    color: var(--ink-secondary);
    font-size: 0.95rem;
}

.search-result-tags {
    font-size: 0.85rem;
    color: var(--accent-blue);
}

.no-results, .search-error {
    color: var(--ink-secondary);
    font-style: italic;
    margin-top: var(--spacing-lg);
}

/* Lab Card (for featured content) */
.lab-card {
    background: white;
    border: 1px solid var(--border-color);
    padding: 30px;
    margin: 40px 0;
    border-radius: 4px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.02);
}

.lab-card h3 {
    margin: 0 0 12px 0;
    font-family: 'Merriweather', serif;
    font-size: 1.2rem;
}

.lab-card p {
    font-size: 0.95rem;
    margin-bottom: 16px;
    color: var(--ink-secondary);
}

.btn-lab {
    display: inline-block;
    background-color: var(--accent-blue);
    color: white;
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 4px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: background 0.2s;
}

.btn-lab:hover {
    background-color: #002244;
    color: white;
}

/* Footer */
footer {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--ink-secondary);
    text-align: center;
}

/* Polaroid Image Style */
img.polaroid {
    background-color: #fff;
    padding: var(--spacing-sm);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    max-width: 100%;
    height: auto;
    display: block;
    margin: var(--spacing-lg) auto;
    border: 1px solid var(--border-color);
}