:root {
    --cnb-primary: #4f46e5;
    --cnb-primary-dark: #4338ca;
    --cnb-text: #1f2430;
    --cnb-muted: #8a93a3;
    --cnb-border: #eceef2;
    --cnb-bg: #f7f8fb;
    --cnb-card: #ffffff;
    --cnb-radius: 16px;
    --cnb-shadow: 0 1px 3px rgba(17, 24, 39, 0.04), 0 8px 24px rgba(17, 24, 39, 0.06);
    --cnb-shadow-hover: 0 4px 12px rgba(79, 70, 229, 0.10), 0 16px 40px rgba(17, 24, 39, 0.08);
    --cnb-font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

body {
    font-family: var(--cnb-font);
    color: var(--cnb-text);
    background: var(--cnb-bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--cnb-primary); text-decoration: none; }
a:hover { color: var(--cnb-primary-dark); }

/* ===== 顶部导航 ===== */
.site-header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--cnb-border);
    box-shadow: 0 1px 12px rgba(17, 24, 39, 0.04);
    position: sticky;
    top: 0;
    z-index: 1030;
}
.site-header .container {
    max-width: 1140px;
}
.site-logo {
    font-size: 19px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--cnb-text);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 9px;
    white-space: nowrap;
}
.site-logo:hover { color: var(--cnb-primary); }
.logo-img {
    display: block;
    width: 40px;
    height: 40px;
    max-width: 40px;
    border-radius: 10px;
    object-fit: cover;
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.45), inset 0 1px 1px rgba(255, 255, 255, 0.35);
    flex: 0 0 auto;
    vertical-align: middle;
    margin-right: 8px;
}

.main-links { gap: 4px; }
.nav-link-item {
    color: #555;
    text-decoration: none;
    font-size: 14.5px;
    font-weight: 500;
    padding: 7px 14px;
    border-radius: 10px;
    transition: all .2s ease;
}
.nav-link-item:hover { color: var(--cnb-primary); background: #f1f3f7; }

.search-box {
    display: flex;
    align-items: center;
    background: #f1f3f7;
    border: 1px solid transparent;
    border-radius: 999px;
    padding: 8px 16px;
    width: 280px;
    transition: all .2s ease;
}
.search-box:focus-within { background: #fff; border-color: var(--cnb-primary); box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.12); }
.search-box i { color: var(--cnb-muted); font-size: 14px; }
.search-box input {
    border: none;
    background: transparent;
    outline: none;
    margin-left: 8px;
    font-size: 14px;
    width: 100%;
    color: var(--cnb-text);
}

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

.user-chip { display: inline-flex; align-items: center; gap: 8px; }
.user-avatar {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--cnb-primary), #8b5cf6);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
}
.user-name { color: #4b5160; font-size: 14px; font-weight: 600; }

.logout-btn {
    background: none;
    border: none;
    cursor: pointer;
    font: inherit;
}

/* ===== 主体布局 ===== */
.main-container {
    max-width: 1140px;
    padding-top: 36px;
    padding-bottom: 40px;
}
.content-col { padding-right: 28px; }
.sidebar-col { padding-left: 12px; }

/* ===== 卡片通用 ===== */
.card-modern {
    background: var(--cnb-card);
    border: 1px solid var(--cnb-border);
    border-radius: var(--cnb-radius);
    box-shadow: var(--cnb-shadow);
    padding: 22px 24px;
    margin-bottom: 22px;
    transition: box-shadow .25s ease, transform .25s ease;
}
.card-modern:hover { box-shadow: var(--cnb-shadow-hover); }

.section-title {
    font-size: 13px;
    font-weight: 700;
    letter-spacing: .08em;
    text-transform: uppercase;
    color: var(--cnb-muted);
    margin: 0 0 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.section-title i { color: var(--cnb-primary); }

/* ===== 文章列表 ===== */
.post-card {
    background: var(--cnb-card);
    border: 1px solid var(--cnb-border);
    border-radius: var(--cnb-radius);
    box-shadow: var(--cnb-shadow);
    padding: 26px 28px;
    margin-bottom: 22px;
    transition: box-shadow .25s ease, transform .25s ease;
}
.post-card:hover {
    box-shadow: var(--cnb-shadow-hover);
    transform: translateY(-2px);
}
.post-title {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin: 0 0 10px;
    line-height: 1.35;
}
.post-title a { color: var(--cnb-text); }
.post-title a:hover { color: var(--cnb-primary); }

.post-meta {
    color: var(--cnb-muted);
    font-size: 13px;
    margin-bottom: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 4px 14px;
    align-items: center;
}
.post-meta a { color: var(--cnb-muted); }
.post-meta a:hover { color: var(--cnb-primary); }
.post-meta .meta-item { display: inline-flex; align-items: center; gap: 5px; }

.post-summary {
    color: #4b5160;
    font-size: 15px;
    line-height: 1.8;
}
.post-summary img { max-width: 100%; border-radius: 10px; }

.post-footer {
    margin-top: 16px;
    padding-top: 14px;
    border-top: 1px solid var(--cnb-border);
    font-size: 13px;
    color: var(--cnb-muted);
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    justify-content: space-between;
}
.post-tags { display: inline-flex; flex-wrap: wrap; gap: 6px; }

/* 标签 chip */
.chip {
    display: inline-block;
    background: #f1f3fb;
    color: var(--cnb-primary);
    font-size: 12px;
    padding: 3px 12px;
    border-radius: 999px;
    text-decoration: none;
    transition: all .2s ease;
}
.chip:hover { background: var(--cnb-primary); color: #fff; }

.read-more {
    font-weight: 600;
    color: var(--cnb-primary);
}
.read-more:hover { color: var(--cnb-primary-dark); }

/* ===== 文章详情 ===== */
.article-card {
    background: var(--cnb-card);
    border: 1px solid var(--cnb-border);
    border-radius: var(--cnb-radius);
    box-shadow: var(--cnb-shadow);
    padding: 36px 40px;
}
.article-title {
    font-size: 30px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--cnb-text);
    margin: 0 0 14px;
    line-height: 1.3;
}
.article-meta {
    color: var(--cnb-muted);
    font-size: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 4px 16px;
    align-items: center;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--cnb-border);
    margin-bottom: 26px;
}
.article-meta a { color: var(--cnb-muted); }
.article-meta a:hover { color: var(--cnb-primary); }

.article-body {
    font-size: 16px;
    line-height: 1.85;
    color: #2c3140;
}
.article-body h1 { font-size: 26px; font-weight: 700; margin: 32px 0 14px; }
.article-body h2 { font-size: 22px; font-weight: 700; margin: 28px 0 12px; }
.article-body h3 { font-size: 19px; font-weight: 700; margin: 24px 0 10px; }
.article-body p { margin: 0 0 16px; }
.article-body img { max-width: 100%; border-radius: 12px; margin: 8px 0; }
.article-body pre {
    background: #0f172a;
    color: #e2e8f0;
    padding: 16px 20px;
    border-radius: 12px;
    overflow: auto;
    font-size: 13.5px;
    line-height: 1.6;
    margin: 16px 0;
}
.article-body code {
    background: #f1f3f7;
    color: #d6336c;
    padding: 2px 6px;
    border-radius: 6px;
    font-size: 13.5px;
}
.article-body pre code { background: transparent; color: inherit; padding: 0; }
.article-body blockquote {
    border-left: 3px solid var(--cnb-primary);
    background: #f8f8ff;
    padding: 10px 18px;
    margin: 16px 0;
    border-radius: 0 10px 10px 0;
    color: #555;
}
.article-body a { color: var(--cnb-primary); text-decoration: underline; text-underline-offset: 3px; }

.article-tags {
    margin-top: 28px;
    padding-top: 20px;
    border-top: 1px solid var(--cnb-border);
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 22px;
    color: var(--cnb-muted);
    font-size: 14px;
}
.back-link:hover { color: var(--cnb-primary); }

/* ===== 侧边栏卡片内部 ===== */
.side-card {
    background: var(--cnb-card);
    border: 1px solid var(--cnb-border);
    border-radius: var(--cnb-radius);
    box-shadow: var(--cnb-shadow);
    padding: 20px 22px;
    margin-bottom: 22px;
}
.side-list { list-style: none; padding: 0; margin: 0; }
.side-list li {
    padding: 9px 0;
    font-size: 14px;
    border-bottom: 1px solid var(--cnb-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.side-list li:last-child { border-bottom: none; }
.side-list li a { color: #4b5160; }
.side-list li a:hover { color: var(--cnb-primary); }
.side-count {
    color: var(--cnb-muted);
    font-size: 12px;
    background: #f1f3f7;
    border-radius: 999px;
    padding: 1px 9px;
}
.side-empty { color: var(--cnb-muted); font-size: 14px; }

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

.author-card { text-align: center; }
.author-avatar {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--cnb-primary), #8b5cf6);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    margin: 0 auto 14px;
}
.author-name { font-size: 17px; font-weight: 700; margin-bottom: 4px; }
.author-bio { color: var(--cnb-muted); font-size: 13px; line-height: 1.6; }

/* 公告 */
.notice-text { font-size: 13.5px; color: #4b5160; line-height: 1.7; }

/* 日历 */
.mini-cal { width: 100%; border-collapse: collapse; font-size: 12px; }
.mini-cal th, .mini-cal td { text-align: center; padding: 5px 0; }
.mini-cal th { color: var(--cnb-muted); font-weight: 600; }
.mini-cal td { color: #4b5160; }
.mini-cal .cal-today { background: var(--cnb-primary); color: #fff; border-radius: 8px; font-weight: 700; }
.mini-cal .cal-empty { color: transparent; }

/* 订阅 */
.subscribe-form { display: flex; gap: 8px; margin-top: 4px; }
.subscribe-form input {
    flex: 1;
    border: 1px solid var(--cnb-border);
    border-radius: 10px;
    padding: 9px 12px;
    font-size: 13px;
    outline: none;
    transition: border-color .2s ease;
}
.subscribe-form input:focus { border-color: var(--cnb-primary); }
.subscribe-form button {
    border: none;
    background: var(--cnb-primary);
    color: #fff;
    border-radius: 10px;
    padding: 9px 16px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
    transition: background .2s ease;
}
.subscribe-form button:hover { background: var(--cnb-primary-dark); }
.subscribe-note { color: var(--cnb-muted); font-size: 12px; margin-top: 8px; }

/* ===== 分页 ===== */
.pager {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin: 28px 0 8px;
    flex-wrap: wrap;
}
.pager a, .pager span {
    display: inline-flex;
    align-items: center;
    padding: 8px 15px;
    border-radius: 10px;
    border: 1px solid var(--cnb-border);
    background: #fff;
    color: #4b5160;
    font-size: 13px;
    text-decoration: none;
    transition: all .2s ease;
}
.pager a:hover { border-color: var(--cnb-primary); color: var(--cnb-primary); }
.pager .current {
    background: var(--cnb-primary);
    color: #fff;
    border-color: var(--cnb-primary);
}

/* ===== 页脚 ===== */
.site-footer {
    border-top: 1px solid var(--cnb-border);
    background: #fff;
    padding: 28px 0;
    color: var(--cnb-muted);
    font-size: 13px;
}

/* ===== 响应式 ===== */
@media (max-width: 991px) {
    .content-col { padding-right: 0; }
    .sidebar-col { padding-left: 0; margin-top: 8px; }
    .article-card { padding: 26px 22px; }
}
@media (max-width: 575px) {
    .search-box { width: 160px; }
    .post-card { padding: 20px 18px; }
}

/* ===== 登录 / 注册页 ===== */
.auth-card {
    border-radius: 20px !important;
    box-shadow: 0 1px 3px rgba(17,24,39,.04), 0 16px 48px rgba(17,24,39,.10) !important;
}
.auth-card .form-control-lg {
    border-radius: 12px;
    padding: 12px 16px;
    font-size: 15px;
    border-color: var(--cnb-border);
    transition: border-color .2s ease, box-shadow .2s ease;
}
.auth-card .form-control-lg:focus {
    border-color: var(--cnb-primary);
    box-shadow: 0 0 0 3px rgba(79,70,229,.14);
}
.auth-card .form-text { color: var(--cnb-muted); }
.auth-card .btn-lg { font-weight: 600; padding: 12px 16px; }

/* ===== Mermaid 流程图 ===== */
.article-body pre.mermaid,
.mermaid {
    background: #f8f9fc;
    border: 1px solid var(--cnb-border);
    border-radius: 12px;
    padding: 18px;
    margin: 18px 0;
    text-align: center;
    overflow-x: auto;
}
.mermaid svg { max-width: 100%; height: auto; margin: 0 auto; }