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

/* === Variables === */
:root {
    --bg: #F5F0E8;
    --text: #2C2C2C;
    --accent: #1B3A5C;
    --bg-secondary: #EDE8DC;
    --border: #D4CFC4;
    --muted: #A09A90;
    --max-width: 720px;
    --font-serif: 'Libre Baskerville', Georgia, serif;
    --font-sans: 'Inter', -apple-system, Helvetica, Arial, sans-serif;
}

/* === Base === */
html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
}

body {
    background-color: var(--bg);
    color: var(--text);
    font-family: var(--font-serif);
    line-height: 1.6;
    min-height: 100vh;
}

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

a:hover {
    text-decoration: underline;
}

/* === Reading Progress Bar === */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--accent);
    z-index: 1000;
    transition: width 0.1s linear;
}

/* === Navigation === */
.site-nav {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1.5rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border);
}

.site-name {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
    letter-spacing: -0.01em;
}

.site-name:hover {
    text-decoration: none;
    color: var(--accent);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    font-family: var(--font-sans);
    font-size: 0.875rem;
}

.nav-links a {
    color: var(--text);
    text-decoration: none;
    transition: color 0.15s;
}

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

/* === Language Switch (typographic) === */
.lang-switch {
    font-family: var(--font-sans);
    font-size: 0.78rem;
    text-decoration: none;
    letter-spacing: 0.03em;
    display: inline-flex;
    align-items: center;
    gap: 0.15rem;
}

.lang-switch:hover {
    text-decoration: none;
}

.lang-option {
    transition: color 0.15s;
}

.lang-active {
    color: var(--accent);
    font-weight: 600;
}

.lang-inactive {
    color: #B5B0A6;
    font-weight: 400;
}

.lang-sep {
    color: #B5B0A6;
    font-weight: 400;
}

.lang-switch:hover .lang-inactive {
    color: var(--accent);
}

/* === Main content === */
.content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 3rem 1.5rem 4rem;
}

/* === Page headings === */
.page-heading {
    font-family: var(--font-sans);
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    color: var(--accent);
    margin-bottom: 2.5rem;
}

/* === Article list === */
.article-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
}

.article-item {
    padding-bottom: 2.5rem;
    border-bottom: 1px solid var(--border);
}

.article-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.article-number {
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--muted);
    letter-spacing: 0.05em;
    margin-bottom: 0.4rem;
    display: block;
}

.article-title-link {
    font-family: var(--font-serif);
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
    line-height: 1.35;
    display: block;
    margin-bottom: 0.6rem;
}

.article-title-link:hover {
    color: var(--accent);
    text-decoration: none;
}

/* === Tags (pills) === */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.tag {
    font-family: var(--font-sans);
    font-size: 0.7rem;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text);
    padding: 0.2rem 0.55rem;
    border-radius: 3px;
    border: 1px solid var(--border);
    letter-spacing: 0.02em;
}

.tags-sm .tag {
    font-size: 0.6rem;
    padding: 0.15rem 0.45rem;
}

/* === More link (Home) === */
.more-link {
    display: block;
    text-align: center;
    margin-top: 4rem;
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--accent);
    letter-spacing: 0.03em;
    opacity: 0.7;
    transition: opacity 0.15s;
}

.more-link:hover {
    opacity: 1;
    text-decoration: none;
}

/* === Tag filter bar (Archive) === */
.tag-filter-bar {
    margin-bottom: 2.5rem;
}

.tag-filter-label {
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.02em;
    margin-bottom: 0.75rem;
    display: block;
}

.tag-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.tag-filter-btn {
    font-family: var(--font-sans);
    font-size: 0.72rem;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 0.3rem 0.65rem;
    border-radius: 3px;
    cursor: pointer;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.tag-filter-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.tag-filter-btn.active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.tag-filter-btn.disabled {
    color: #C8C3BA;
    border-color: #E2DED6;
    background: var(--bg);
    cursor: default;
    pointer-events: none;
    opacity: 0.5;
}

/* === Article page === */
.article-header {
    margin-bottom: 2.5rem;
}

.article-header .article-number {
    margin-bottom: 0.6rem;
}

.article-header .article-title {
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 700;
    color: var(--text);
    line-height: 1.3;
    margin-bottom: 0.8rem;
}

.article-header .tags {
    margin-bottom: 0;
}

/* === Article body === */
.article-body {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--text);
}

.article-body p {
    margin-bottom: 1.5rem;
}

.article-body h2 {
    font-size: 1.4rem;
    font-weight: 700;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
}

.article-body h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin-top: 2rem;
    margin-bottom: 0.75rem;
}

.article-body blockquote {
    border-left: 3px solid var(--accent);
    padding-left: 1.25rem;
    margin: 1.5rem 0;
    color: #555;
    font-style: italic;
}

.article-body ul,
.article-body ol {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
}

.article-body li {
    margin-bottom: 0.4rem;
}

.article-body code {
    font-size: 0.9em;
    background: var(--bg-secondary);
    padding: 0.15em 0.35em;
    border-radius: 3px;
}

.article-body pre {
    background: var(--bg-secondary);
    padding: 1.25rem;
    border-radius: 4px;
    overflow-x: auto;
    margin-bottom: 1.5rem;
}

.article-body pre code {
    background: none;
    padding: 0;
}

.article-body a {
    color: var(--accent);
    text-decoration: underline;
}

.article-body hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 2rem 0;
}

/* === Share buttons === */
.share-bar {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 0.75rem;
    align-items: center;
}

.share-btn {
    font-family: var(--font-sans);
    font-size: 0.78rem;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 0.45rem 0.85rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.share-btn:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    text-decoration: none;
}

.share-btn.copied {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

/* === About page === */
.about-text {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    line-height: 1.8;
    margin-bottom: 0.5rem;
}

/* === Contact page === */
.contact-items {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    align-items: center;
    padding-top: 2rem;
}

.contact-link {
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 0.65rem 1.5rem;
    border-radius: 4px;
    text-decoration: none;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.contact-link:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    text-decoration: none;
}

/* === 404 === */
.not-found {
    text-align: center;
    padding-top: 4rem;
}

.not-found h1 {
    font-family: var(--font-serif);
    font-size: 2rem;
    margin-bottom: 1rem;
}

.not-found p {
    font-family: var(--font-sans);
    font-size: 0.95rem;
    color: #666;
}

/* === Footer === */
.site-footer {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
    border-top: 1px solid var(--border);
    text-align: center;
}

.site-footer .footer-name {
    font-family: var(--font-serif);
    font-size: 0.85rem;
    color: var(--text);
    opacity: 0.5;
}

/* === Responsive === */
@media (max-width: 600px) {
    .site-nav {
        flex-direction: column;
        gap: 1rem;
        padding: 1.5rem 1rem 1rem;
    }

    .nav-links {
        gap: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    .content {
        padding: 2rem 1rem 3rem;
    }

    .article-title-link {
        font-size: 1.2rem;
    }

    .article-header .article-title {
        font-size: 1.6rem;
    }

    .article-body {
        font-size: 1.05rem;
    }
}