/* ============================================
   Zibll-Lite 轻量主题 CSS
   保留 Zibll 子比主题 1:1 视觉风格
   移除 bootstrap/animate.css/font-awesome/swiper 依赖
   ============================================ */

/* === CSS Variables === */
:root {
    --main-max-width: 1200px;
    --posts-card-scale: 70%;
    --theme-color: #f04494;
    --focus-color: var(--theme-color);
    --focus-shadow-color: rgba(253, 83, 161, 0.4);
    --key-color: #333;
    --main-color: #4e5358;
    --main-shadow: rgba(116, 116, 116, 0.08);
    --muted-color: #777;
    --muted-2-color: #999;
    --muted-3-color: #b1b1b1;
    --body-bg-color: #f5f6f7;
    --main-bg-color: #fff;
    --muted-bg-color: #eee;
    --main-border-color: rgba(50, 50, 50, 0.06);
    --muted-border-color: rgba(0, 0, 0, 0.03);
    --main-radius: 8px;
    --blur-bg: rgba(255, 255, 255, 0.8);
    --header-bg: var(--blur-bg);
    --header-color: var(--main-color);
    --footer-bg: var(--main-bg-color);
    --footer-color: var(--muted-2-color);
    --font-size-base: 14px;
    --font-size-lg: 16px;
    --font-size-sm: 12px;
    --line-height: 1.6;
    --header-height: 60px;
}

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

html {
    -webkit-text-size-adjust: 100%;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    font-size: var(--font-size-base);
    line-height: var(--line-height);
    color: var(--main-color);
    background: var(--body-bg-color);
    -webkit-font-smoothing: antialiased;
    padding-top: var(--header-height);
}

a {
    color: var(--key-color);
    text-decoration: none;
    transition: color 0.2s, background 0.3s, opacity 0.3s, box-shadow 0.3s, transform 0.3s;
}
a:hover { color: var(--theme-color); }

img { max-width: 100%; height: auto; vertical-align: middle; }
ul, ol { list-style: none; }
h1, h2, h3, h4, h5, h6 { color: var(--key-color); font-weight: 600; line-height: 1.4; }
h1 { font-size: 24px; } h2 { font-size: 20px; } h3 { font-size: 18px; } h4 { font-size: 16px; }

/* === Container === */
.container {
    max-width: var(--main-max-width);
    margin: 0 auto;
    padding: 0 15px;
}

/* === Header === */
.header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-height);
    background: var(--header-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--main-border-color);
    z-index: 1000;
    display: flex;
    align-items: center;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: var(--main-max-width);
    margin: 0 auto;
    padding: 0 15px;
}

.branding {
    display: flex;
    align-items: center;
    gap: 10px;
}

.branding .logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--key-color);
    white-space: nowrap;
}

.branding .logo img { max-height: 40px; }

/* Navigation */
.nav-menu { display: flex; align-items: center; gap: 5px; }
.nav-menu li { position: relative; }
.nav-menu a {
    display: block;
    padding: 8px 14px;
    font-size: 14px;
    color: var(--header-color);
    border-radius: var(--main-radius);
    white-space: nowrap;
}
.nav-menu a:hover,
.nav-menu .current-menu-item > a {
    color: var(--theme-color);
    background: rgba(240, 68, 148, 0.06);
}

/* Mobile menu toggle */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--header-color);
    cursor: pointer;
    padding: 5px;
}

/* === Main Layout === */
.main-content {
    display: flex;
    gap: 20px;
    padding: 20px 0;
}

.content-wrap { flex: 1; min-width: 0; }

/* === Sidebar === */
.sidebar {
    width: 300px;
    flex-shrink: 0;
}

.sidebar .widget {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 16px;
    margin-bottom: 20px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.sidebar .widget-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--key-color);
    padding-bottom: 10px;
    border-bottom: 1px solid var(--main-border-color);
}

.sidebar .widget ul li { padding: 6px 0; border-bottom: 1px solid var(--muted-border-color); }
.sidebar .widget ul li:last-child { border-bottom: none; }
.sidebar .widget ul li a { color: var(--main-color); font-size: 13px; }
.sidebar .widget ul li a:hover { color: var(--theme-color); }

/* === Post Cards (列表页卡片) === */
.posts-row {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.post-card {
    display: flex;
    gap: 16px;
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 16px;
    box-shadow: 0 1px 3px var(--main-shadow);
    transition: box-shadow 0.3s, transform 0.3s;
    overflow: hidden;
}

.post-card:hover {
    box-shadow: 0 4px 20px rgba(0,0,0,0.12);
    transform: translateY(-2px);
}

.post-card-thumb {
    width: calc(var(--posts-card-scale));
    max-width: 220px;
    min-width: 140px;
    flex-shrink: 0;
    border-radius: calc(var(--main-radius) - 2px);
    overflow: hidden;
    position: relative;
}

.post-card-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    aspect-ratio: 16 / 10;
    display: block;
}

.post-card-body {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.post-card-title {
    font-size: 17px;
    font-weight: 600;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

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

.post-card-excerpt {
    font-size: 13px;
    color: var(--muted-color);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin: 8px 0;
}

.post-card-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: var(--font-size-sm);
    color: var(--muted-2-color);
    flex-wrap: wrap;
}

.post-card-meta span { display: inline-flex; align-items: center; gap: 4px; }

.post-card-meta .meta-cat a {
    color: var(--theme-color);
    background: rgba(240, 68, 148, 0.08);
    padding: 2px 8px;
    border-radius: 20px;
    font-size: 11px;
}

/* Post Card - Grid (首页紧凑型) */
.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 16px;
}

.posts-grid .post-card {
    flex-direction: column;
    padding: 12px;
}

.posts-grid .post-card-thumb {
    width: 100%;
    max-width: 100%;
    min-width: auto;
    margin-bottom: 10px;
}

.posts-grid .post-card-thumb img { aspect-ratio: 16 / 9; }

.posts-grid .post-card-title { font-size: 15px; }

/* === Category Cover === */
.cat-cover {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 24px;
    margin-bottom: 20px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.cat-cover h1 { font-size: 22px; margin-bottom: 6px; }
.cat-cover .cat-desc { color: var(--muted-color); font-size: 14px; }

/* === Tab Nav (首页) === */
.home-tabs {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 16px;
    margin-bottom: 20px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.tab-nav {
    display: flex;
    gap: 4px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.tab-nav-item {
    padding: 8px 16px;
    font-size: 14px;
    border-radius: 20px;
    cursor: pointer;
    color: var(--muted-color);
    background: transparent;
    border: none;
    transition: all 0.2s;
}

.tab-nav-item:hover { color: var(--theme-color); background: rgba(240, 68, 148, 0.06); }
.tab-nav-item.active {
    color: #fff;
    background: var(--theme-color);
}

.tab-pane { display: none; }
.tab-pane.active { display: block; }

/* === Pagination === */
.pagination {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin-top: 24px;
    flex-wrap: wrap;
}

.pagination .page-numbers {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
    padding: 0 12px;
    border-radius: var(--main-radius);
    font-size: 14px;
    color: var(--main-color);
    background: var(--main-bg-color);
    box-shadow: 0 1px 3px var(--main-shadow);
    transition: all 0.2s;
}

.pagination .current {
    background: var(--theme-color);
    color: #fff;
}

.pagination a:hover {
    background: rgba(240, 68, 148, 0.1);
    color: var(--theme-color);
}

/* === Single Post (详情页) === */
.single-post-wrap {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 24px;
    box-shadow: 0 1px 3px var(--main-shadow);
    margin-bottom: 20px;
}

.single-post-header { margin-bottom: 20px; }

.single-post-header .post-title {
    font-size: 24px;
    font-weight: 700;
    line-height: 1.4;
    color: var(--key-color);
}

.single-post-header .post-meta-row {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-top: 12px;
    font-size: 13px;
    color: var(--muted-2-color);
    flex-wrap: wrap;
}

.post-meta-row .meta-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    overflow: hidden;
}

.post-meta-row .meta-avatar img { width: 100%; height: 100%; object-fit: cover; }

.single-post-content {
    font-size: 15px;
    line-height: 1.8;
    color: var(--main-color);
    word-break: break-word;
}

.single-post-content h2 { font-size: 20px; margin: 28px 0 14px; padding-bottom: 8px; border-bottom: 1px solid var(--main-border-color); }
.single-post-content h3 { font-size: 18px; margin: 24px 0 12px; }
.single-post-content p { margin-bottom: 16px; }
.single-post-content img { border-radius: var(--main-radius); margin: 12px 0; }
.single-post-content blockquote {
    border-left: 4px solid var(--theme-color);
    padding: 10px 16px;
    margin: 16px 0;
    background: rgba(240, 68, 148, 0.04);
    border-radius: 0 var(--main-radius) var(--main-radius) 0;
    color: var(--muted-color);
}
.single-post-content pre {
    background: #2d2d2d;
    color: #ccc;
    padding: 16px;
    border-radius: var(--main-radius);
    overflow-x: auto;
    font-size: 13px;
    line-height: 1.5;
    margin: 16px 0;
}
.single-post-content code { background: var(--muted-bg-color); padding: 2px 6px; border-radius: 4px; font-size: 0.9em; }
.single-post-content pre code { background: none; padding: 0; }
.single-post-content ul, .single-post-content ol { padding-left: 24px; margin-bottom: 16px; }
.single-post-content ul { list-style: disc; }
.single-post-content ol { list-style: decimal; }
.single-post-content li { margin-bottom: 6px; }
.single-post-content a { color: var(--theme-color); }
.single-post-content a:hover { text-decoration: underline; }

/* Post Tags */
.post-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 24px;
    padding-top: 16px;
    border-top: 1px solid var(--main-border-color);
}

.post-tags a {
    display: inline-block;
    padding: 4px 12px;
    background: rgba(240, 68, 148, 0.06);
    color: var(--theme-color);
    border-radius: 20px;
    font-size: 12px;
}

/* Post Nav (上下篇) */
.post-nav {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    margin-top: 20px;
}

.post-nav > div {
    flex: 1;
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 14px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.post-nav .nav-label { font-size: 12px; color: var(--muted-2-color); margin-bottom: 4px; }
.post-nav .nav-title { font-size: 14px; color: var(--key-color); display: -webkit-box; -webkit-line-clamp: 1; -webkit-box-orient: vertical; overflow: hidden; }
.post-nav .nav-title:hover { color: var(--theme-color); }
.post-nav-next { text-align: right; }

/* === Related Posts === */
.related-posts {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 20px;
    margin-top: 20px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.related-posts h3 {
    font-size: 18px;
    margin-bottom: 16px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--main-border-color);
}

.related-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 12px; }
.related-item { display: flex; gap: 10px; align-items: flex-start; }
.related-item-thumb {
    width: 80px;
    height: 56px;
    flex-shrink: 0;
    border-radius: 4px;
    overflow: hidden;
}
.related-item-thumb img { width: 100%; height: 100%; object-fit: cover; }
.related-item-info { flex: 1; min-width: 0; }
.related-item-title {
    font-size: 13px;
    font-weight: 600;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.4;
}
.related-item-title a { color: var(--key-color); }
.related-item-title a:hover { color: var(--theme-color); }
.related-item-date { font-size: 11px; color: var(--muted-2-color); margin-top: 4px; }

/* === Comments === */
.comments-area {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 20px;
    margin-top: 20px;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.comments-title { font-size: 18px; margin-bottom: 16px; padding-bottom: 10px; border-bottom: 1px solid var(--main-border-color); }

.comment-list { margin-top: 16px; }
.comment-list li { margin-bottom: 16px; padding-bottom: 16px; border-bottom: 1px solid var(--muted-border-color); }

.comment-body { display: flex; gap: 12px; }
.comment-author-avatar { width: 40px; height: 40px; border-radius: 50%; overflow: hidden; flex-shrink: 0; }
.comment-author-avatar img { width: 100%; height: 100%; object-fit: cover; }

.comment-content { flex: 1; min-width: 0; }
.comment-author { font-weight: 600; font-size: 14px; color: var(--key-color); }
.comment-meta { font-size: 12px; color: var(--muted-2-color); margin: 4px 0; }
.comment-text { font-size: 14px; line-height: 1.6; word-break: break-word; }
.comment-text p { margin-bottom: 8px; }

/* === Footer === */
.footer {
    background: var(--footer-bg);
    color: var(--footer-color);
    padding: 40px 0 20px;
    margin-top: 40px;
    border-top: 1px solid var(--main-border-color);
}

.footer-inner {
    max-width: var(--main-max-width);
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-copyright { font-size: 13px; }

/* === Buttons === */
.but {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 8px 20px;
    border: none;
    border-radius: var(--main-radius);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
    text-align: center;
    gap: 6px;
}
.but-primary { background: var(--theme-color); color: #fff; }
.but-primary:hover { background: #d93a7e; color: #fff; }
.but-outline { border: 1px solid var(--main-border-color); background: transparent; color: var(--main-color); }
.but-outline:hover { border-color: var(--theme-color); color: var(--theme-color); }
.but-sm { padding: 4px 12px; font-size: 12px; }
.but-lg { padding: 12px 28px; font-size: 16px; }
.btn-block { display: flex; width: 100%; }

/* === Search Form === */
.search-form {
    display: flex;
    gap: 0;
}
.search-form input[type="search"] {
    flex: 1;
    padding: 8px 14px;
    border: 1px solid var(--main-border-color);
    border-right: none;
    border-radius: var(--main-radius) 0 0 var(--main-radius);
    font-size: 14px;
    background: var(--body-bg-color);
    outline: none;
    color: var(--main-color);
}
.search-form input[type="search"]:focus { border-color: var(--theme-color); }
.search-form button {
    padding: 8px 16px;
    border: 1px solid var(--theme-color);
    background: var(--theme-color);
    color: #fff;
    border-radius: 0 var(--main-radius) var(--main-radius) 0;
    cursor: pointer;
    font-size: 14px;
}

/* === Loading & Empty === */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--muted-2-color);
}
.empty-state h3 { font-size: 20px; margin-bottom: 8px; color: var(--muted-color); }

/* === Utility === */
.text-center { text-align: center; }
.text-muted { color: var(--muted-color); }
.radius { border-radius: var(--main-radius); }
.mt10 { margin-top: 10px; } .mt20 { margin-top: 20px; }
.mb10 { margin-bottom: 10px; } .mb20 { margin-bottom: 20px; }
.mr6 { margin-right: 6px; } .ml6 { margin-left: 6px; } .ml10 { margin-left: 10px; }
.clearfix::after { content: ""; display: table; clear: both; }
.screen-reader-text { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); }

/* === Sticky Post === */
.post-card.sticky { border-left: 3px solid var(--theme-color); }

/* === Top Banner / Notice === */
.site-notice {
    background: linear-gradient(135deg, var(--theme-color), #ff6ba6);
    color: #fff;
    text-align: center;
    padding: 10px 16px;
    font-size: 14px;
    border-radius: var(--main-radius);
    margin-bottom: 20px;
}

/* === Archive Header === */
.archive-header {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    padding: 20px;
    margin-bottom: 20px;
    text-align: center;
    box-shadow: 0 1px 3px var(--main-shadow);
}

.archive-header h1 { font-size: 22px; }
.archive-header .archive-desc { color: var(--muted-color); font-size: 14px; margin-top: 6px; }

/* === Sticky Badge === */
.sticky-badge {
    position: absolute;
    top: 8px;
    left: 8px;
    background: var(--theme-color);
    color: #fff;
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 10px;
    z-index: 2;
}

/* === No Thumb Placeholder === */
.no-thumb {
    transition: background 0.3s;
}
.post-card:hover .no-thumb {
    background: var(--muted-border-color) !important;
}

/* === Breadcrumb === */
.breadcrumb a { color: var(--muted-2-color); }
.breadcrumb a:hover { color: var(--theme-color); }
.breadcrumb span { color: var(--muted-color); }

/* ============================================
   Hero Banner (首页全屏Banner)
   ============================================ */

.hero-banner {
    position: relative;
    width: 100%;
    min-height: 360px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    overflow: hidden;
    margin-bottom: 30px;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 20% 50%, rgba(240,68,148,.15) 0%, transparent 50%),
                radial-gradient(circle at 80% 30%, rgba(100,149,237,.1) 0%, transparent 50%);
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 60px 20px 70px;
    max-width: 800px;
}

.hero-title {
    font-size: 42px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 12px;
    letter-spacing: 2px;
    text-shadow: 0 2px 10px rgba(0,0,0,.3);
}

.hero-desc {
    font-size: 16px;
    color: rgba(255,255,255,.7);
    margin-bottom: 30px;
    line-height: 1.6;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.hero-stat {
    text-align: center;
    padding: 0 20px;
    border-right: 1px solid rgba(255,255,255,.1);
}

.hero-stat:last-child { border-right: none; }

.hero-stat strong {
    display: block;
    font-size: 28px;
    font-weight: 700;
    color: var(--theme-color);
    line-height: 1.2;
}

.hero-stat span {
    font-size: 13px;
    color: rgba(255,255,255,.5);
    text-transform: uppercase;
    letter-spacing: 1px;
}

@media (max-width: 600px) {
    .hero-banner { min-height: 280px; }
    .hero-title { font-size: 28px; }
    .hero-desc { font-size: 14px; }
    .hero-stats { gap: 20px; }
    .hero-stat { padding: 0 12px; }
    .hero-stat strong { font-size: 22px; }
}

/* ============================================
   下载组件 (Download Section)
   ============================================ */

.zib-download-box {
    background: var(--main-bg-color);
    border-radius: var(--main-radius);
    margin: 24px 0;
    overflow: hidden;
    box-shadow: 0 1px 3px var(--main-shadow);
    border: 1px solid var(--main-border-color);
}

.zib-dl-inner { padding: 0; }

.zib-dl-hd {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 20px;
    background: linear-gradient(135deg, var(--theme-color), #ff6ba6);
    color: #fff;
    font-size: 15px;
    font-weight: 600;
}

.zib-dl-icon { font-size: 18px; }

.zib-dl-bd { padding: 16px 20px; }

.zib-dl-tips {
    text-align: center;
    padding: 20px;
    color: var(--muted-color);
    font-size: 14px;
}

.zib-dl-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid var(--muted-border-color);
    flex-wrap: wrap;
}

.zib-dl-item:last-child { border-bottom: none; }

.zib-dl-type-icon {
    font-size: 24px;
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--body-bg-color);
    border-radius: 8px;
}

.zib-dl-info {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.zib-dl-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--key-color);
}

.zib-dl-pwd {
    font-size: 12px;
    color: var(--muted-2-color);
}

.zib-dl-pwd code {
    background: var(--body-bg-color);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 12px;
    color: var(--theme-color);
    cursor: pointer;
}

.zib-dl-copy {
    font-size: 11px;
    padding: 1px 8px;
    border: 1px solid var(--main-border-color);
    background: var(--body-bg-color);
    border-radius: 3px;
    cursor: pointer;
    color: var(--muted-color);
    transition: all .2s;
}

.zib-dl-copy:hover {
    border-color: var(--theme-color);
    color: var(--theme-color);
}

.zib-dl-btn {
    flex-shrink: 0;
    display: inline-flex;
    align-items: center;
    padding: 8px 22px;
    background: var(--theme-color);
    color: #fff;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    transition: all .2s;
}

.zib-dl-btn:hover {
    background: #d93a7e;
    color: #fff;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(240,68,148,.4);
}

.zib-dl-ft {
    padding: 10px 20px;
    font-size: 11px;
    color: var(--muted-2-color);
    text-align: center;
    border-top: 1px solid var(--muted-border-color);
    background: var(--body-bg-color);
}

@media (max-width: 480px) {
    .zib-dl-item { flex-direction: column; align-items: flex-start; }
    .zib-dl-btn { width: 100%; justify-content: center; }
}

/* ============================================
   响应式 (Responsive)
   ============================================ */

@media (max-width: 900px) {
    .main-content { flex-direction: column; }
    .sidebar { width: 100%; }
    
    .nav-menu {
        display: none;
        position: fixed;
        top: var(--header-height);
        left: 0; right: 0;
        background: var(--main-bg-color);
        flex-direction: column;
        padding: 10px;
        box-shadow: 0 4px 12px var(--main-shadow);
        z-index: 999;
    }
    .nav-menu.open { display: flex; }
    .nav-menu a { padding: 12px 16px; width: 100%; }
    
    .menu-toggle { display: block; }
    
    .posts-grid { grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); }
    
    .post-card-thumb { max-width: 160px; min-width: 100px; }
    .post-card-title { font-size: 15px; }
    
    .single-post-header .post-title { font-size: 20px; }
    .single-post-content { font-size: 14px; }
    
    .post-nav { flex-direction: column; }
    .post-nav-next { text-align: left; }
    
    .related-list { grid-template-columns: 1fr 1fr; }
    
    .footer-inner { flex-direction: column; text-align: center; }
}

@media (max-width: 480px) {
    body { padding-top: 52px; }
    :root { --header-height: 52px; }
    .container { padding: 0 10px; }
    .post-card { padding: 10px; gap: 10px; }
    .post-card-thumb { max-width: 120px; min-width: 80px; }
    .post-card-title { font-size: 14px; }
    .post-card-meta { font-size: 11px; gap: 8px; }
    .posts-grid { grid-template-columns: 1fr 1fr; gap: 10px; }
    .posts-grid .post-card-thumb img { aspect-ratio: 16 / 10; }
    .single-post-wrap { padding: 16px; }
    .related-list { grid-template-columns: 1fr; }
    
    .tab-nav { gap: 2px; }
    .tab-nav-item { padding: 6px 12px; font-size: 12px; }
}

/* Back to Top */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 42px;
    height: 42px;
    background: var(--main-bg-color);
    border: 1px solid var(--main-border-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    box-shadow: 0 2px 8px var(--main-shadow);
    z-index: 100;
    font-size: 18px;
    color: var(--muted-color);
}
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--theme-color); color: #fff; border-color: var(--theme-color); }