/* ============================================================
   Blog module — extends academic.css (warm paper design system).
   Uses the shared palette/font variables defined there; the dark
   theme itself (variable redefinitions) lives in academic.css,
   so blog components adapt automatically.
   ============================================================ */

/* smooth theme swap on blog-specific components */
.post-card, .tag-pill, .toc-link {
    transition: background-color .25s ease, color .25s ease, border-color .25s ease;
}

/* ---------------- Blog list page ---------------- */

.blog-hero { padding: 72px 0 40px; }

.blog-hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.2rem);
    font-weight: 600;
    letter-spacing: -.01em;
    margin-bottom: 10px;
}

.blog-hero .subtitle {
    font-family: var(--font-mono);
    font-size: .78rem;
    letter-spacing: .14em;
    text-transform: uppercase;
    color: var(--ink-3);
    margin: 0;
}

.blog-controls {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin: 34px 0 30px;
}

.blog-search { position: relative; flex: 1; min-width: 220px; max-width: 380px; }

.blog-search input {
    width: 100%;
    font-family: var(--font-mono);
    font-size: .8rem;
    letter-spacing: .04em;
    color: var(--ink);
    background: var(--panel);
    border: 1px solid var(--line-strong);
    border-radius: 8px;
    padding: 10px 14px;
    outline: none;
    transition: border-color .2s, box-shadow .2s;
}

.blog-search input::placeholder { color: var(--ink-3); }

.blog-search input:focus {
    border-color: var(--coral);
    box-shadow: 0 0 0 3px rgba(217, 119, 87, .15);
}

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

.tag-pill {
    font-family: var(--font-mono);
    font-size: .66rem;
    font-weight: 600;
    letter-spacing: .12em;
    text-transform: uppercase;
    color: var(--ink-2);
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 5px 13px;
    cursor: pointer;
    transition: all .18s ease;
}

.tag-pill:hover {
    border-color: var(--coral);
    color: var(--coral-deep);
}

.tag-pill.active {
    background: var(--coral);
    border-color: var(--coral);
    color: #fff;
}

.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 22px;
    padding-bottom: 72px;
}

.post-card {
    position: relative;
    display: flex;
    flex-direction: column;
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 24px 26px;
    box-shadow: var(--shadow-card);
    animation: fadeInUp .5s ease both;
    transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}

.post-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lift);
    border-color: rgba(217, 119, 87, .45);
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: none; }
}

.post-card-meta {
    display: flex;
    gap: 8px;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 12px;
}

.post-card-date {
    font-family: var(--font-mono);
    font-size: .74rem;
    font-weight: 500;
    letter-spacing: .06em;
    color: var(--coral-deep);
}

.mini-tag {
    font-family: var(--font-mono);
    font-size: .62rem;
    font-weight: 600;
    letter-spacing: .1em;
    text-transform: uppercase;
    color: var(--ink-2);
    background: var(--panel-2);
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 2px 9px;
}

.post-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    line-height: 1.35;
    letter-spacing: -.01em;
    margin-bottom: 10px;
}

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

/* whole card is clickable */
.post-card-title a::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
}

.post-card:hover .post-card-title a { color: var(--coral-deep); }
.post-card-title a:hover { text-decoration: none; }

.post-card-excerpt {
    flex: 1;
    font-size: .92rem;
    line-height: 1.7;
    color: var(--ink-2);
    margin: 0 0 16px;
}

.read-more {
    font-family: var(--font-mono);
    font-size: .7rem;
    font-weight: 500;
    letter-spacing: .14em;
    text-transform: uppercase;
    color: var(--coral-deep);
}

.read-more::after {
    content: " →";
    display: inline-block;
    transition: transform .2s ease;
}

.post-card:hover .read-more::after { transform: translateX(4px); }

.blog-empty {
    grid-column: 1 / -1;
    text-align: center;
    font-family: var(--font-mono);
    font-size: .82rem;
    letter-spacing: .08em;
    color: var(--ink-3);
    padding: 70px 0;
}

/* ---------------- Post reader page ---------------- */

.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    width: 0;
    background: linear-gradient(90deg, var(--coral-deep), var(--coral));
    z-index: 100;
    transition: width .1s linear;
}

.post-layout {
    display: flex;
    gap: 56px;
    padding: 64px 0 72px;
}

.post-main { flex: 1; min-width: 0; }

.post-toc-col { width: 230px; flex-shrink: 0; }

@media (max-width: 991px) {
    .post-toc-col { display: none; }
}

.toc-sidebar {
    position: sticky;
    top: 96px;
    border-left: 2px solid var(--line);
    max-height: 75vh;
    overflow-y: auto;
}

.toc-title {
    font-family: var(--font-mono);
    font-size: .66rem;
    font-weight: 600;
    letter-spacing: .16em;
    text-transform: uppercase;
    color: var(--ink-3);
    padding-left: 16px;
    margin-bottom: 8px;
}

.toc-link {
    display: block;
    font-size: .84rem;
    line-height: 1.45;
    padding: 5px 16px;
    color: var(--ink-3);
    border-left: 2px solid transparent;
    margin-left: -2px;
}

.toc-link:hover { color: var(--coral-deep); text-decoration: none; }

.toc-link.active {
    color: var(--coral-deep);
    border-left-color: var(--coral);
    font-weight: 500;
}

.toc-link.toc-h3 { padding-left: 32px; font-size: .78rem; }

.post-header { margin-bottom: 36px; }

.post-header h1 {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 600;
    line-height: 1.25;
    letter-spacing: -.01em;
    margin-bottom: 16px;
}

.post-header-meta {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    align-items: center;
    font-family: var(--font-mono);
    font-size: .74rem;
    font-weight: 500;
    letter-spacing: .08em;
    color: var(--ink-3);
}

.post-header-meta .post-date { color: var(--coral-deep); }

/* article body */
.post-content {
    font-size: .98rem;
    line-height: 1.85;
    color: var(--ink);
    animation: fadeInUp .4s ease both;
}

.post-content h2 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -.01em;
    margin: 48px 0 16px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--line);
}

.post-content h3 {
    font-size: 1.18rem;
    font-weight: 600;
    margin: 32px 0 12px;
}

.post-content p { margin: 0 0 18px; }

.post-content ul, .post-content ol { margin: 0 0 18px; padding-left: 24px; }
.post-content li { margin-bottom: 6px; }

.post-content img {
    display: block;
    max-width: 100%;
    margin: 24px auto;
    border-radius: 10px;
    border: 1px solid var(--line);
    box-shadow: var(--shadow-card);
}

.post-content blockquote {
    margin: 22px 0;
    padding: 14px 20px;
    border-left: 3px solid var(--coral);
    border-radius: 0 8px 8px 0;
    background: var(--coral-dim);
    color: var(--ink-2);
}

.post-content blockquote p:last-child { margin-bottom: 0; }

.post-content hr { border: none; border-top: 1px dashed var(--line-strong); margin: 36px 0; }

.post-content table {
    width: 100%;
    margin: 22px 0;
    border-collapse: collapse;
    font-size: .9rem;
}

.post-content th, .post-content td {
    border: 1px solid var(--line);
    padding: 9px 13px;
    text-align: left;
}

.post-content th {
    font-family: var(--font-mono);
    font-size: .7rem;
    font-weight: 600;
    letter-spacing: .1em;
    text-transform: uppercase;
    color: var(--ink-2);
    background: var(--panel-2);
}

.post-content code {
    font-family: var(--font-mono);
    font-size: .86em;
    background: var(--panel-2);
    color: var(--coral-deep);
    border: 1px solid var(--line);
    border-radius: 5px;
    padding: 1px 6px;
}

/* fenced code block: feed-bar style header + copy button */
.code-block {
    margin: 22px 0;
    border: 1px solid var(--line);
    border-radius: 12px;
    overflow: hidden;
    background: var(--panel);
}

.code-block-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    font-family: var(--font-mono);
    font-size: .66rem;
    font-weight: 500;
    letter-spacing: .12em;
    text-transform: uppercase;
    color: var(--ink-2);
    background: var(--panel-2);
    border-bottom: 1px solid var(--line);
    padding: 7px 14px;
}

.copy-btn {
    font-family: var(--font-mono);
    font-size: .64rem;
    font-weight: 600;
    letter-spacing: .12em;
    text-transform: uppercase;
    color: var(--coral-deep);
    background: none;
    border: none;
    padding: 2px 4px;
    cursor: pointer;
    border-radius: 4px;
    transition: color .15s ease;
}

.copy-btn:hover { color: var(--coral); }

.code-block pre {
    margin: 0;
    padding: 16px;
    overflow-x: auto;
    background: var(--panel);
}

.code-block pre code,
.code-block pre code.hljs {
    display: block;
    background: transparent;
    border: none;
    padding: 0;
    color: var(--ink);
    font-size: .85rem;
    line-height: 1.65;
}

/* prev / next */
.post-nav {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    margin-top: 56px;
    padding-top: 26px;
    border-top: 1px solid var(--line);
}

.post-nav a {
    max-width: 48%;
    font-family: var(--font-serif);
    font-size: 1rem;
    font-weight: 600;
    color: var(--ink);
}

.post-nav a:hover { color: var(--coral-deep); text-decoration: none; }

.post-nav .nav-label {
    display: block;
    font-family: var(--font-mono);
    font-size: .66rem;
    font-weight: 500;
    letter-spacing: .14em;
    text-transform: uppercase;
    color: var(--ink-3);
    margin-bottom: 6px;
}

.post-nav .nav-next { text-align: right; margin-left: auto; }

.post-back { margin-top: 36px; }

/* ---------------- Responsive & reduced motion ---------------- */

@media (max-width: 560px) {
    .blog-hero { padding: 52px 0 32px; }
    .blog-controls { flex-direction: column; align-items: stretch; }
    .blog-search { max-width: none; }
    .posts-grid { grid-template-columns: 1fr; }
    .post-layout { padding: 48px 0 56px; }
}

@media (prefers-reduced-motion: reduce) {
    .post-card, .post-card:hover { animation: none; transform: none; transition: none; }
    .post-content { animation: none; }
    .read-more::after { transition: none; }
    .reading-progress { transition: none; }
}