/* Blog shares the site's typography and colour tokens from learn.css. */
.blog-page { min-height: 100vh; display: flex; flex-direction: column; }
.blog-skip { position: fixed; left: 1rem; top: -5rem; z-index: 300; background: var(--cream); color: var(--black); padding: .8rem 1rem; }
.blog-skip:focus { top: 1rem; }
.blog-main { width: 100%; max-width: 1080px; margin: 0 auto; padding: 100px var(--gutter) 0; flex: 1; }
.blog-main:focus { outline: none; }
.blog-crumb { display: flex; gap: .8rem; align-items: center; font-size: .8rem; color: var(--sub); }
.blog-crumb a { color: var(--sub); text-underline-offset: 4px; }
.blog-heading { display: grid; grid-template-columns: 1.2fr 1fr; gap: 3rem; align-items: end; padding: 3.5rem 0 2.8rem; }
.blog-eyebrow { color: var(--gold); font-size: .75rem; letter-spacing: .12em; margin-bottom: 1rem; }
.blog-heading h1 { font-size: clamp(2.4rem, 4.5vw, 3.65rem); font-weight: 400; line-height: 1.4; color: var(--cream); letter-spacing: -.04em; }
.blog-heading h1 em { color: var(--gold); font-style: normal; }
.blog-intro { font-size: 1rem; line-height: 2; padding-bottom: .6rem; max-width: 26rem; }
.blog-topics { display: flex; flex-wrap: wrap; list-style: none; gap: .7rem 1.6rem; border-top: 1px solid var(--border-mid); border-bottom: 1px solid var(--border-mid); padding: 1rem 0; color: var(--gold); font-size: .8rem; }
.blog-topics li + li { border-left: 1px solid var(--border-mid); padding-left: 1.6rem; }
.blog-posts { padding: 2.6rem 0 3rem; }
.blog-section-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; }
.blog-section-heading h2 { font-size: .9rem; font-weight: 500; color: var(--cream); }
.blog-section-heading > span { font-family: var(--font-display); font-size: 1.2rem; color: var(--sub); font-style: italic; }
.blog-empty { display: grid; grid-template-columns: 150px 1fr; gap: 2rem; align-items: center; padding: 3.5rem 0 2rem; }
.blog-empty-mark { font-family: var(--font-display); font-weight: 300; font-style: italic; color: var(--gold); font-size: 6rem; border-right: 1px solid var(--border-mid); line-height: 1; padding: 1rem 1.5rem 2rem 0; }
.blog-empty h3 { font-size: clamp(1.4rem, 2.4vw, 1.8rem); font-weight: 400; color: var(--cream); margin-bottom: .8rem; }
.blog-empty p:not(.blog-eyebrow) { font-size: .95rem; line-height: 1.9; }
.blog-text-link { display: inline-flex; align-items: center; gap: 1rem; color: var(--gold); text-decoration: none; border-bottom: 1px solid var(--gold); margin-top: 1.1rem; min-height: 44px; font-size: .9rem; }
.blog-text-link:hover { color: var(--cream); }
.blog-contact { display: flex; gap: 2rem; align-items: center; justify-content: space-between; border-top: 1px solid var(--border-mid); padding: 2rem 0 3.5rem; }
.blog-contact h2 { font-size: 1.15rem; color: var(--cream); font-weight: 400; margin-bottom: .4rem; }
.blog-contact p { font-size: .85rem; color: var(--sub); }
.blog-menu { display: none; }
.blog-menu summary { cursor: pointer; list-style: none; color: var(--gold); min-height: 44px; display: flex; align-items: center; gap: .8rem; font-size: .85rem; }
.blog-menu summary::-webkit-details-marker { display: none; }
.blog-menu[open] summary span { transform: rotate(45deg); }
.blog-menu-links { position: absolute; top: 60px; left: 0; right: 0; background: var(--surface); border-bottom: 1px solid var(--border-mid); padding: .5rem var(--gutter) 1rem; box-shadow: 0 8px 16px #1f1b170a; }
.blog-menu-links a { display: block; padding: .85rem 0; color: var(--text); text-decoration: none; border-bottom: 1px solid var(--border); }
.blog-menu-links a[aria-current] { color: var(--gold); }
@media (max-width: 768px) {
    .blog-page .nav-links { display: none; }
    .blog-menu { display: block; }
    .blog-main { padding-top: 85px; }
    .blog-heading { grid-template-columns: 1fr; gap: 1.5rem; padding: 2.4rem 0 1.8rem; }
    .blog-heading h1 { font-size: clamp(2.25rem, 7vw, 3.2rem); }
    .blog-intro { font-size: .95rem; }
    .blog-topics { gap: .5rem 1rem; }
    .blog-topics li + li { padding-left: 1rem; }
    .blog-empty { grid-template-columns: 1fr; gap: .8rem; padding: 2rem 0 1rem; }
    .blog-empty-mark { font-size: 3.5rem; padding: 0; border: 0; }
    .blog-section-heading > span { font-size: 1rem; }
    .blog-empty h3 { font-size: 1.35rem; }
    .blog-contact { align-items: flex-start; flex-direction: column; gap: 1.3rem; padding-bottom: 2.5rem; }
    .blog-contact .btn { padding: .8rem 1.2rem; }
}
/* 文章列表 */
.blog-list { list-style: none; margin-top: 1.6rem; border-top: 1px solid var(--border-mid); }
.blog-item { border-bottom: 1px solid var(--border-mid); }
.blog-item a { display: grid; grid-template-columns: 9rem 1fr; column-gap: 2rem; padding: 1.8rem 0; color: inherit; text-decoration: none; }
.blog-item-meta { grid-row: span 2; display: flex; flex-direction: column; gap: .45rem; font-family: var(--font-mono); font-size: .75rem; color: var(--sub); }
.blog-item-meta span { color: var(--gold); }
.blog-item h3 { font-size: clamp(1.1rem, 1.8vw, 1.35rem); font-weight: 400; line-height: 1.6; color: var(--cream); margin-bottom: .5rem; }
.blog-item a:hover h3, .blog-item a:focus-visible h3 { color: var(--gold); }
.blog-item p:not(.blog-item-meta) { font-size: .92rem; line-height: 1.9; max-width: 44rem; }
.blog-item--featured a { grid-template-columns: 1fr; padding: 2.6rem 0 2.4rem; }
.blog-item--featured .blog-item-meta { grid-row: auto; flex-direction: row; gap: 1.2rem; margin-bottom: 1rem; }
.blog-item--featured h3 { font-family: var(--font-display); font-size: clamp(1.7rem, 3.4vw, 2.5rem); line-height: 1.35; letter-spacing: -.01em; max-width: 20em; text-wrap: balance; margin-bottom: .9rem; }
.blog-item--featured p:not(.blog-item-meta) { font-size: 1rem; max-width: 38rem; color: var(--text); }
@media (max-width: 768px) {
    .blog-item a { grid-template-columns: 1fr; padding: 1.4rem 0; }
    .blog-item-meta { grid-row: auto; flex-direction: row; gap: 1rem; margin-bottom: .6rem; }
}
/* 分類按鈕＋文章卡片（radio＋CSS 篩選，不需要 JavaScript） */
.blog-filter { margin-top: 1.6rem; }
.blog-filter-input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.blog-chips { display: flex; flex-wrap: wrap; gap: .6rem; margin-bottom: 2rem; }
.blog-chips label {
    display: inline-flex; align-items: center; gap: .45rem; min-height: 44px; padding: 0 1.15rem;
    border: 1px solid var(--border-mid); border-radius: 999px; cursor: pointer;
    font-size: .88rem; color: var(--text); transition: background .2s, color .2s, border-color .2s;
}
.blog-chips label span { font-family: var(--font-mono); font-size: .75rem; color: var(--sub); }
.blog-chips label:hover { border-color: var(--gold-dim); color: var(--cream); }
#cat-all:checked ~ .blog-chips label[for="cat-all"],
#cat-ai:checked ~ .blog-chips label[for="cat-ai"],
#cat-local:checked ~ .blog-chips label[for="cat-local"] { background: var(--cream); border-color: var(--cream); color: var(--black); }
#cat-all:checked ~ .blog-chips label[for="cat-all"] span,
#cat-ai:checked ~ .blog-chips label[for="cat-ai"] span,
#cat-local:checked ~ .blog-chips label[for="cat-local"] span { color: inherit; opacity: .7; }
#cat-all:focus-visible ~ .blog-chips label[for="cat-all"],
#cat-ai:focus-visible ~ .blog-chips label[for="cat-ai"],
#cat-local:focus-visible ~ .blog-chips label[for="cat-local"] { outline: 2px solid var(--gold); outline-offset: 2px; }
#cat-ai:checked ~ .blog-grid .blog-card:not([data-cat="ai"]),
#cat-local:checked ~ .blog-grid .blog-card:not([data-cat="local"]) { display: none; }
#cat-ai:checked ~ .blog-grid .blog-card--featured,
#cat-local:checked ~ .blog-grid .blog-card--featured { grid-column: auto; }

.blog-grid { list-style: none; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.25rem; }
.blog-card a {
    display: flex; flex-direction: column; height: 100%; padding: 1.8rem 1.8rem 1.5rem;
    border: 1px solid var(--border-mid); border-radius: 14px; background: var(--surface);
    color: inherit; text-decoration: none; transition: border-color .25s, transform .25s cubic-bezier(.2,.8,.2,1), box-shadow .25s;
}
.blog-card a:hover { border-color: var(--gold-dim); transform: translateY(-2px); box-shadow: 0 10px 24px -14px rgba(60,40,10,.25); }
.blog-card a:focus-visible { outline: 2px solid var(--gold); outline-offset: 3px; }
.blog-card-cat { align-self: flex-start; font-size: .78rem; color: var(--gold-dim); border: 1px solid var(--gold-faint); border-radius: 999px; padding: .2rem .75rem; margin-bottom: 1.1rem; }
.blog-card h3 { font-family: var(--font-display); font-weight: 500; font-size: clamp(1.2rem, 2vw, 1.45rem); line-height: 1.5; color: var(--cream); margin-bottom: .8rem; text-wrap: balance; }
.blog-card p { font-size: .92rem; line-height: 1.9; color: var(--text); margin-bottom: 1.4rem; }
.blog-card-foot { margin-top: auto; display: flex; justify-content: space-between; gap: 1rem; font-family: var(--font-mono); font-size: .75rem; color: var(--sub); }
.blog-card-foot span { color: var(--gold-dim); }
.blog-card--featured { grid-column: 1 / -1; }
.blog-card--featured a { padding: clamp(2rem, 4vw, 3rem); }
.blog-card--featured h3 { font-size: clamp(1.6rem, 3.2vw, 2.4rem); line-height: 1.35; max-width: 20em; }
.blog-card--featured p { font-size: 1rem; max-width: 40rem; }
@media (max-width: 768px) {
    .blog-grid { grid-template-columns: 1fr; }
    .blog-card a { padding: 1.5rem 1.35rem 1.3rem; }
    .blog-chips label { padding: 0 .95rem; }
}
@media (prefers-reduced-motion: reduce) { .blog-card a { transition: none; } .blog-card a:hover { transform: none; } }
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .blog-page *, .blog-page *::before, .blog-page *::after { animation: none !important; transition: none !important; }
}